Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1665947 > unrolled thread
| Started by | David Howells <dhowells@redhat.com> |
|---|---|
| First post | 2017-06-14 17:20 +0200 |
| Last post | 2017-06-16 18:00 +0200 |
| Articles | 20 on this page of 42 — 8 participants |
Back to article view | Back to linux.kernel
[RFC][PATCH 00/27] VFS: Introduce filesystem context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 11/27] VFS: Remove unused code after filesystem context changes [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 20/27] NFS: Split nfs_parse_mount_options() [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 03/27] VFS: Make get_mnt_ns() return the namespace [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
Re: [PATCH 03/27] VFS: Make get_mnt_ns() return the namespace [ver #5] Al Viro <viro@ZenIV.linux.org.uk> - 2017-06-15 11:20 +0200
[PATCH 27/27] kernfs, sysfs, cgroup: Support fs_context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
Re: [PATCH 27/27] kernfs, sysfs, cgroup: Support fs_context [ver #5] Tejun Heo <tj@kernel.org> - 2017-06-14 20:00 +0200
Re: [PATCH 27/27] ... and the intel_rdt driver David Howells <dhowells@redhat.com> - 2017-06-15 00:40 +0200
[PATCH 26/27] cpuset: Use fs_context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 16/27] proc: Add fs_context support to procfs [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
Re: [PATCH 16/27] proc: Add fs_context support to procfs [ver #5] Al Viro <viro@ZenIV.linux.org.uk> - 2017-06-15 12:20 +0200
[PATCH 01/27] Provide a function to create a NUL-terminated string from unterminated data [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 09/27] VFS: Add LSM hooks for filesystem context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 25/27] ipc: Convert mqueue fs to fs_context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
Re: [PATCH 25/27] ipc: Convert mqueue fs to fs_context [ver #5] Al Viro <viro@ZenIV.linux.org.uk> - 2017-06-15 12:10 +0200
Re: [PATCH 25/27] ipc: Convert mqueue fs to fs_context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-15 16:50 +0200
[PATCH 23/27] NFS: Do some tidying of the parsing code [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 22/27] NFS: Add a small buffer in nfs_fs_context to avoid string dup [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 14/27] VFS: Add a sample program for fsopen/fsmount [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 02/27] VFS: Clean up whitespace in fs/namespace.c and fs/super.c [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 04/27] VFS: Make get_filesystem() return the affected filesystem [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 18/27] NFS: Constify mount argument match tables [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:20 +0200
[PATCH 05/27] VFS: Provide empty name qstr [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:30 +0200
[PATCH 15/27] procfs: Move proc_fill_super() to fs/proc/root.c [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:30 +0200
[PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:30 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] Randy Dunlap <rdunlap@infradead.org> - 2017-06-14 20:10 +0200
Updated docs David Howells <dhowells@redhat.com> - 2017-06-15 01:00 +0200
Re: Updated docs Randy Dunlap <rdunlap@infradead.org> - 2017-06-15 04:00 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] Casey Schaufler <casey@schaufler-ca.com> - 2017-06-14 22:10 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 22:50 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] Casey Schaufler <casey@schaufler-ca.com> - 2017-06-14 23:00 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] Theodore Ts'o <tytso@mit.edu> - 2017-06-17 12:00 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-17 16:20 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] Jeff Layton <jlayton@redhat.com> - 2017-06-17 17:00 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] Randy Dunlap <rdunlap@infradead.org> - 2017-06-17 17:20 +0200
Re: [PATCH 08/27] VFS: Introduce the structs and doc for a filesystem context [ver #5] David Howells <dhowells@redhat.com> - 2017-06-19 09:50 +0200
[PATCH 21/27] NFS: Deindent nfs_fs_context_parse_option() [ver #5] David Howells <dhowells@redhat.com> - 2017-06-14 17:30 +0200
Re: [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags [ver #5] Al Viro <viro@ZenIV.linux.org.uk> - 2017-06-15 11:50 +0200
Re: [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags [ver #5] Christoph Hellwig <hch@infradead.org> - 2017-06-16 11:10 +0200
Re: [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags [ver #5] David Howells <dhowells@redhat.com> - 2017-06-16 17:00 +0200
Re: [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags [ver #5] Christoph Hellwig <hch@infradead.org> - 2017-06-16 18:00 +0200
Re: [PATCH 07/27] VFS: Differentiate mount flags (MS_*) from internal superblock flags [ver #5] David Howells <dhowells@redhat.com> - 2017-06-16 18:00 +0200
Page 1 of 3 [1] 2 3 Next page →
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [RFC][PATCH 00/27] VFS: Introduce filesystem context [ver #5] |
| Message-ID | <tSifn-6QJ-7@gated-at.bofh.it> |
Here are a set of patches to create a filesystem context prior to setting
up a new mount, populating it with the parsed options/binary data, creating
the superblock and then effecting the mount. This is also used for remount
since much of the parsing stuff is common in many filesystems.
This allows namespaces and other information to be conveyed through the
mount procedure. A method is also provided by which supplementary error
information to be retrieved (so many things can go wrong during a mount
that a small integer isn't really sufficient to convey the issue).
This also allows Miklós Szeredi's idea of doing:
fd = fsopen("nfs");
write(fd, "option=val", ...);
fsmount(fd, "/mnt");
that he presented at LSF-2017 to be implemented (see the relevant patches
in the series). I add a
prctl(PR_ERRMSG_ENABLE, 1);
call to enable error message buffering and:
prctl(PR_ERRMSG_READ, ...);
to retrieve and discard the latest error message.
I didn't use netlink as that would make the core kernel depend on
CONFIG_NET and CONFIG_NETLINK and would introduce network namespacing
issues.
I've implemented mount context handling for procfs, nfs, mqueue, cpuset,
kernfs, sysfs and cgroup filesystems.
Significant changes:
ver #5:
(*) Renamed sb_config -> fs_context and adjusted variable names.
(*) Differentiated the flags in sb->s_flags (now named SB_*) from those
passed to mount(2) (named MS_*).
(*) Renamed __vfs_new_fs_context() to vfs_new_fs_context() and made the
caller always provide a struct file_system_type pointer and the
parameters required.
(*) Got rid of vfs_submount_fc() in favour of passing
FS_CONTEXT_FOR_SUBMOUNT to vfs_new_fs_context(). The purpose is now
used more.
(*) Call ->validate() on the remount path.
(*) Got rid of the inode locking in sys_fsmount().
(*) Call security_sb_mountpoint() in the mount(2) path.
ver #4:
(*) Split the sb_config patch up somewhat.
(*) Made the supplementary error string facility something attached to the
task_struct rather than the sb_config so that error messages can be
obtained from NFS doing a mount-root-and-pathwalk inside the
nfs_get_tree() operation.
Further, made this managed and read by prctl rather than through the
mount fd so that it's more generally available.
ver #3:
(*) Rebased on 4.12-rc1.
(*) Split the NFS patch up somewhat.
ver #2:
(*) Removed the ->fill_super() from sb_config_operations and passed it in
directly to functions that want to call it. NFS now calls
nfs_fill_super() directly rather than jumping through a pointer to it
since there's only the one option at the moment.
(*) Removed ->mnt_ns and ->sb from sb_config and moved ->pid_ns into
proc_sb_config.
(*) Renamed create_super -> get_tree.
(*) Renamed struct mount_context to struct sb_config and amended various
variable names.
(*) sys_fsmount() acquired AT_* flags and MS_* flags (for MNT_* flags)
arguments.
ver #1:
(*) Split the sb_config stuff out into its own header.
(*) Support non-context aware filesystems through a special set of
sb_config operations.
(*) Stored the created superblock and root dentry into the sb_config after
creation rather than directly into a vfsmount. This allows some
arguments to be removed to various NFS functions.
(*) Added an explicit superblock-creation step. This allows a created
superblock to then be mounted multiple times.
(*) Added a flag to say that the sb_config is degraded and cannot have
another go at having a superblock creation whilst getting rid of the
one that says it's already mounted.
Further developments:
(*) Implement sb reconfiguration (for now it returns ENOANO).
(*) Implement mount context support in more filesystems, ext4 being next
on my list.
(*) Move the walk-from-root stuff that nfs has to generic code so that you
can do something akin to:
mount /dev/sda1:/foo/bar /mnt
See nfs_follow_remote_path() and mount_subtree(). This is slightly
tricky in NFS as we have to prevent referral loops.
(*) Work out how to get at the error message incurred by submounts
encountered during nfs_follow_remote_path().
Should the error message be moved to task_struct and made more
general, perhaps retrieved with a prctl() function?
(*) Clean up/consolidate the security functions. Possibly add a
validation hook to be called at the same time as the mount context
validate op.
The patches can be found here also:
http://git.kernel.org/cgit/linux/kernel/git/dhowells/linux-fs.git/log/?h=mount-context
David
---
David Howells (27):
Provide a function to create a NUL-terminated string from unterminated data
VFS: Clean up whitespace in fs/namespace.c and fs/super.c
VFS: Make get_mnt_ns() return the namespace
VFS: Make get_filesystem() return the affected filesystem
VFS: Provide empty name qstr
Provide supplementary error message facility
VFS: Differentiate mount flags (MS_*) from internal superblock flags
VFS: Introduce the structs and doc for a filesystem context
VFS: Add LSM hooks for filesystem context
VFS: Implement a filesystem superblock creation/configuration context
VFS: Remove unused code after filesystem context changes
VFS: Implement fsopen() to prepare for a mount
VFS: Implement fsmount() to effect a pre-configured mount
VFS: Add a sample program for fsopen/fsmount
procfs: Move proc_fill_super() to fs/proc/root.c
proc: Add fs_context support to procfs
NFS: Move mount parameterisation bits into their own file
NFS: Constify mount argument match tables
NFS: Rename struct nfs_parsed_mount_data to struct nfs_fs_context
NFS: Split nfs_parse_mount_options()
NFS: Deindent nfs_fs_context_parse_option()
NFS: Add a small buffer in nfs_fs_context to avoid string dup
NFS: Do some tidying of the parsing code
NFS: Add fs_context support.
ipc: Convert mqueue fs to fs_context
cpuset: Use fs_context
kernfs, sysfs, cgroup: Support fs_context
Documentation/filesystems/mounting.txt | 436 +++++
Documentation/filesystems/porting | 2
arch/x86/entry/syscalls/syscall_32.tbl | 2
arch/x86/entry/syscalls/syscall_64.tbl | 2
drivers/base/devtmpfs.c | 4
drivers/mtd/mtdsuper.c | 6
drivers/staging/lustre/lustre/llite/file.c | 2
drivers/staging/lustre/lustre/llite/llite_lib.c | 16
drivers/staging/lustre/lustre/llite/namei.c | 2
drivers/video/fbdev/core/fbmon.c | 6
drivers/video/fbdev/edid.h | 2
fs/9p/vfs_super.c | 6
fs/Makefile | 3
fs/adfs/super.c | 4
fs/affs/amigaffs.c | 4
fs/affs/bitmap.c | 8
fs/affs/super.c | 20
fs/afs/super.c | 4
fs/befs/ChangeLog | 2
fs/befs/linuxvfs.c | 6
fs/btrfs/ctree.h | 2
fs/btrfs/dev-replace.c | 2
fs/btrfs/disk-io.c | 12
fs/btrfs/extent_io.c | 6
fs/btrfs/inode.c | 2
fs/btrfs/ioctl.c | 6
fs/btrfs/root-tree.c | 2
fs/btrfs/super.c | 60 -
fs/btrfs/sysfs.c | 4
fs/btrfs/volumes.c | 6
fs/cachefiles/bind.c | 2
fs/ceph/super.c | 8
fs/cifs/cifs_fs_sb.h | 2
fs/cifs/cifsfs.c | 12
fs/cifs/cifsglob.h | 4
fs/cifs/inode.c | 2
fs/cifs/xattr.c | 8
fs/coda/inode.c | 4
fs/cramfs/inode.c | 4
fs/dcache.c | 8
fs/ecryptfs/main.c | 10
fs/efs/super.c | 6
fs/ext2/balloc.c | 4
fs/ext2/ialloc.c | 4
fs/ext2/super.c | 30
fs/ext4/ext4_jbd2.c | 2
fs/ext4/file.c | 2
fs/ext4/fsync.c | 2
fs/ext4/ialloc.c | 2
fs/ext4/inode.c | 4
fs/ext4/mmp.c | 2
fs/ext4/super.c | 102 +
fs/f2fs/checkpoint.c | 2
fs/f2fs/f2fs.h | 2
fs/f2fs/gc.c | 2
fs/f2fs/super.c | 24
fs/fat/fatent.c | 8
fs/fat/inode.c | 12
fs/fat/misc.c | 4
fs/fat/namei_msdos.c | 2
fs/filesystems.c | 3
fs/freevxfs/vxfs_super.c | 4
fs/fs-writeback.c | 2
fs/fs_context.c | 501 +++++
fs/fsopen.c | 273 +++
fs/fuse/inode.c | 12
fs/gfs2/dir.c | 3
fs/gfs2/glops.c | 2
fs/gfs2/ops_fstype.c | 20
fs/gfs2/quota.c | 2
fs/gfs2/recovery.c | 2
fs/gfs2/super.c | 14
fs/gfs2/sys.c | 2
fs/gfs2/trans.c | 2
fs/hfs/mdb.c | 10
fs/hfs/super.c | 18
fs/hfsplus/super.c | 30
fs/hpfs/alloc.c | 4
fs/hpfs/dir.c | 2
fs/hpfs/map.c | 2
fs/hpfs/super.c | 20
fs/inode.c | 10
fs/internal.h | 4
fs/isofs/inode.c | 4
fs/jffs2/fs.c | 10
fs/jffs2/os-linux.h | 2
fs/jffs2/super.c | 6
fs/jffs2/wbuf.c | 4
fs/jfs/jfs_mount.c | 2
fs/jfs/super.c | 22
fs/kernfs/mount.c | 90 +
fs/libfs.c | 22
fs/locks.c | 2
fs/minix/inode.c | 8
fs/mount.h | 3
fs/namei.c | 5
fs/namespace.c | 508 ++++--
fs/ncpfs/inode.c | 4
fs/nfs/Makefile | 6
fs/nfs/client.c | 74 -
fs/nfs/dir.c | 2
fs/nfs/fs_context.c | 1499 ++++++++++++++++
fs/nfs/fscache.c | 2
fs/nfs/getroot.c | 72 -
fs/nfs/internal.h | 131 +
fs/nfs/namespace.c | 76 +
fs/nfs/nfs3_fs.h | 2
fs/nfs/nfs3client.c | 6
fs/nfs/nfs3proc.c | 2
fs/nfs/nfs4_fs.h | 4
fs/nfs/nfs4client.c | 82 -
fs/nfs/nfs4namespace.c | 208 +-
fs/nfs/nfs4proc.c | 3
fs/nfs/nfs4super.c | 220 +-
fs/nfs/proc.c | 2
fs/nfs/super.c | 1836 ++------------------
fs/nilfs2/inode.c | 4
fs/nilfs2/mdt.c | 2
fs/nilfs2/segment.c | 2
fs/nilfs2/super.c | 40
fs/nilfs2/the_nilfs.c | 6
fs/notify/fsnotify.c | 2
fs/nsfs.c | 5
fs/ntfs/super.c | 56 -
fs/ocfs2/file.c | 2
fs/ocfs2/super.c | 38
fs/ocfs2/xattr.c | 2
fs/openpromfs/inode.c | 4
fs/orangefs/super.c | 6
fs/overlayfs/super.c | 10
fs/pipe.c | 3
fs/proc/inode.c | 50 -
fs/proc/internal.h | 6
fs/proc/root.c | 211 ++
fs/proc_namespace.c | 10
fs/qnx4/inode.c | 4
fs/qnx6/inode.c | 4
fs/quota/quota.c | 2
fs/reiserfs/inode.c | 4
fs/reiserfs/journal.c | 8
fs/reiserfs/prints.c | 6
fs/reiserfs/super.c | 34
fs/reiserfs/xattr.c | 10
fs/romfs/super.c | 4
fs/squashfs/super.c | 4
fs/statfs.c | 4
fs/super.c | 277 ++-
fs/sync.c | 6
fs/sysfs/mount.c | 59 -
fs/sysv/balloc.c | 2
fs/sysv/ialloc.c | 2
fs/sysv/inode.c | 4
fs/sysv/super.c | 4
fs/ubifs/file.c | 2
fs/ubifs/io.c | 2
fs/ubifs/super.c | 22
fs/ubifs/ubifs.h | 4
fs/udf/super.c | 18
fs/ufs/balloc.c | 8
fs/ufs/ialloc.c | 10
fs/ufs/super.c | 52 -
fs/xfs/xfs_mount.c | 4
fs/xfs/xfs_quotaops.c | 10
fs/xfs/xfs_super.c | 12
fs/xfs/xfs_super.h | 2
include/linux/cgroup.h | 3
include/linux/dcache.h | 5
include/linux/fb.h | 2
include/linux/fs.h | 66 +
include/linux/fs_context.h | 86 +
include/linux/kernfs.h | 37
include/linux/lsm_hooks.h | 47 -
include/linux/mount.h | 2
include/linux/nfs_xdr.h | 7
include/linux/sched.h | 29
include/linux/security.h | 39
include/linux/string.h | 1
include/linux/syscalls.h | 3
include/uapi/linux/bfs_fs.h | 2
include/uapi/linux/magic.h | 1
include/uapi/linux/prctl.h | 6
init/do_mounts.c | 6
ipc/mqueue.c | 90 +
kernel/cgroup/cgroup-internal.h | 42
kernel/cgroup/cgroup-v1.c | 291 ++-
kernel/cgroup/cgroup.c | 172 +-
kernel/cgroup/cpuset.c | 58 -
kernel/exit.c | 1
kernel/fork.c | 1
kernel/sys.c | 38
kernel/sys_ni.c | 4
mm/shmem.c | 10
mm/util.c | 24
samples/fsmount/test-fsmount.c | 92 +
scripts/gdb/linux/constants.py.in | 12
scripts/gdb/linux/proc.py | 8
security/apparmor/include/lib.h | 2
security/security.c | 35
security/selinux/hooks.c | 201 ++
.../selftests/mount/unprivileged-remount-test.c | 8
200 files changed, 5839 insertions(+), 3415 deletions(-)
create mode 100644 Documentation/filesystems/mounting.txt
create mode 100644 fs/fs_context.c
create mode 100644 fs/fsopen.c
create mode 100644 fs/nfs/fs_context.c
create mode 100644 include/linux/fs_context.h
create mode 100644 samples/fsmount/test-fsmount.c
[toc] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 11/27] VFS: Remove unused code after filesystem context changes [ver #5] |
| Message-ID | <tSifo-6QJ-19@gated-at.bofh.it> |
| In reply to | #1665947 |
Remove code that is now unused after the filesystem context changes.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/internal.h | 2 --
fs/super.c | 53 ---------------------------------------------
include/linux/lsm_hooks.h | 2 --
include/linux/security.h | 6 -----
security/security.c | 5 ----
security/selinux/hooks.c | 22 +------------------
6 files changed, 1 insertion(+), 89 deletions(-)
diff --git a/fs/internal.h b/fs/internal.h
index 08d7816f8686..da679deec12f 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -89,8 +89,6 @@ extern struct file *get_empty_filp(void);
*/
extern int do_remount_sb(struct super_block *, int, void *, int, struct fs_context *);
extern bool trylock_super(struct super_block *sb);
-extern struct dentry *mount_fs(struct file_system_type *,
- int, const char *, void *);
extern struct super_block *user_get_super(dev_t);
/*
diff --git a/fs/super.c b/fs/super.c
index 8ef5222d6932..3a83e783a5d2 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -1326,59 +1326,6 @@ struct dentry *mount_single(struct file_system_type *fs_type,
}
EXPORT_SYMBOL(mount_single);
-struct dentry *
-mount_fs(struct file_system_type *type, int flags, const char *name, void *data)
-{
- struct dentry *root;
- struct super_block *sb;
- char *secdata = NULL;
- int error = -ENOMEM;
-
- if (data && !(type->fs_flags & FS_BINARY_MOUNTDATA)) {
- secdata = alloc_secdata();
- if (!secdata)
- goto out;
-
- error = security_sb_copy_data(data, secdata);
- if (error)
- goto out_free_secdata;
- }
-
- root = type->mount(type, flags, name, data);
- if (IS_ERR(root)) {
- error = PTR_ERR(root);
- goto out_free_secdata;
- }
- sb = root->d_sb;
- BUG_ON(!sb);
- WARN_ON(!sb->s_bdi);
- sb->s_flags |= SB_BORN;
-
- error = security_sb_kern_mount(sb, flags, secdata);
- if (error)
- goto out_sb;
-
- /*
- * filesystems should never set s_maxbytes larger than MAX_LFS_FILESIZE
- * but s_maxbytes was an unsigned long long for many releases. Throw
- * this warning for a little while to try and catch filesystems that
- * violate this rule.
- */
- WARN((sb->s_maxbytes < 0), "%s set sb->s_maxbytes to "
- "negative value (%lld)\n", type->name, sb->s_maxbytes);
-
- up_write(&sb->s_umount);
- free_secdata(secdata);
- return root;
-out_sb:
- dput(root);
- deactivate_locked_super(sb);
-out_free_secdata:
- free_secdata(secdata);
-out:
- return ERR_PTR(error);
-}
-
/*
* Setup private BDI for given superblock. It gets automatically cleaned up
* in generic_shutdown_super().
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 62500658cc9f..9bddbb28a2fc 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -1415,7 +1415,6 @@ union security_list_options {
void (*sb_free_security)(struct super_block *sb);
int (*sb_copy_data)(char *orig, char *copy);
int (*sb_remount)(struct super_block *sb, void *data);
- int (*sb_kern_mount)(struct super_block *sb, int flags, void *data);
int (*sb_show_options)(struct seq_file *m, struct super_block *sb);
int (*sb_statfs)(struct dentry *dentry);
int (*sb_mount)(const char *dev_name, const struct path *path,
@@ -1732,7 +1731,6 @@ struct security_hook_heads {
struct list_head sb_free_security;
struct list_head sb_copy_data;
struct list_head sb_remount;
- struct list_head sb_kern_mount;
struct list_head sb_show_options;
struct list_head sb_statfs;
struct list_head sb_mount;
diff --git a/include/linux/security.h b/include/linux/security.h
index e7c774fdffd9..26b4de453ead 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -235,7 +235,6 @@ int security_sb_alloc(struct super_block *sb);
void security_sb_free(struct super_block *sb);
int security_sb_copy_data(char *orig, char *copy);
int security_sb_remount(struct super_block *sb, void *data);
-int security_sb_kern_mount(struct super_block *sb, int flags, void *data);
int security_sb_show_options(struct seq_file *m, struct super_block *sb);
int security_sb_statfs(struct dentry *dentry);
int security_sb_mount(const char *dev_name, const struct path *path,
@@ -571,11 +570,6 @@ static inline int security_sb_remount(struct super_block *sb, void *data)
return 0;
}
-static inline int security_sb_kern_mount(struct super_block *sb, int flags, void *data)
-{
- return 0;
-}
-
static inline int security_sb_show_options(struct seq_file *m,
struct super_block *sb)
{
diff --git a/security/security.c b/security/security.c
index 27b195966cad..c2aa121a8ca4 100644
--- a/security/security.c
+++ b/security/security.c
@@ -367,11 +367,6 @@ int security_sb_remount(struct super_block *sb, void *data)
return call_int_hook(sb_remount, 0, sb, data);
}
-int security_sb_kern_mount(struct super_block *sb, int flags, void *data)
-{
- return call_int_hook(sb_kern_mount, 0, sb, flags, data);
-}
-
int security_sb_show_options(struct seq_file *m, struct super_block *sb)
{
return call_int_hook(sb_show_options, 0, m, sb);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index c93a21119fe3..f146087a608d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -2775,25 +2775,6 @@ static int selinux_sb_remount(struct super_block *sb, void *data)
goto out_free_opts;
}
-static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
-{
- const struct cred *cred = current_cred();
- struct common_audit_data ad;
- int rc;
-
- rc = superblock_doinit(sb, data);
- if (rc)
- return rc;
-
- /* Allow all mounts performed by the kernel */
- if (flags & SB_KERNMOUNT)
- return 0;
-
- ad.type = LSM_AUDIT_DATA_DENTRY;
- ad.u.dentry = sb->s_root;
- return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
-}
-
static int selinux_sb_statfs(struct dentry *dentry)
{
const struct cred *cred = current_cred();
@@ -2978,7 +2959,7 @@ static int selinux_sb_get_tree(struct fs_context *fc)
return rc;
/* Allow all mounts performed by the kernel */
- if (fc->sb_flags & MS_KERNMOUNT)
+ if (fc->sb_flags & SB_KERNMOUNT)
return 0;
ad.type = LSM_AUDIT_DATA_DENTRY;
@@ -6339,7 +6320,6 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
- LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
LSM_HOOK_INIT(sb_mount, selinux_mount),
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 20/27] NFS: Split nfs_parse_mount_options() [ver #5] |
| Message-ID | <tSifo-6QJ-25@gated-at.bofh.it> |
| In reply to | #1665947 |
Split nfs_parse_mount_options() to move the prologue, list-splitting and
epilogue into one function and the per-option processing into another.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/nfs/fs_context.c | 143 +++++++++++++++++++++++++++++----------------------
fs/nfs/internal.h | 3 +
2 files changed, 83 insertions(+), 63 deletions(-)
diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
index 91e412e68183..e3e431e3a1fc 100644
--- a/fs/nfs/fs_context.c
+++ b/fs/nfs/fs_context.c
@@ -494,46 +494,18 @@ static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
}
/*
- * Error-check and convert a string of mount options from user space into
- * a data structure. The whole mount string is processed; bad options are
- * skipped as they are encountered. If there were no errors, return 1;
- * otherwise return 0 (zero).
+ * Parse a single mount option in "key[=val]" form.
*/
-int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
+static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
{
- char *p, *string, *secdata;
- int rc, sloppy = 0, invalid_option = 0;
- unsigned short protofamily = AF_UNSPEC;
- unsigned short mountfamily = AF_UNSPEC;
-
- if (!raw) {
- dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
- return 1;
- }
- dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
-
- secdata = alloc_secdata();
- if (!secdata)
- goto out_nomem;
-
- rc = security_sb_copy_data(raw, secdata);
- if (rc)
- goto out_security_failure;
-
- rc = security_sb_parse_opts_str(secdata, &ctx->lsm_opts);
- if (rc)
- goto out_security_failure;
-
- free_secdata(secdata);
+ char *string;
+ int rc;
- while ((p = strsep(&raw, ",")) != NULL) {
+ {
substring_t args[MAX_OPT_ARGS];
unsigned long option;
int token;
- if (!*p)
- continue;
-
dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", p);
token = match_token(p, nfs_mount_option_tokens, args);
@@ -737,7 +709,7 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
if (!rc) {
dfprintk(MOUNT, "NFS: unrecognized "
"security flavor\n");
- return 0;
+ return -EINVAL;
}
break;
case Opt_proto:
@@ -747,22 +719,22 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
token = match_token(string,
nfs_xprt_protocol_tokens, args);
- protofamily = AF_INET;
+ ctx->protofamily = AF_INET;
switch (token) {
case Opt_xprt_udp6:
- protofamily = AF_INET6;
+ ctx->protofamily = AF_INET6;
case Opt_xprt_udp:
ctx->flags &= ~NFS_MOUNT_TCP;
ctx->nfs_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_xprt_tcp6:
- protofamily = AF_INET6;
+ ctx->protofamily = AF_INET6;
case Opt_xprt_tcp:
ctx->flags |= NFS_MOUNT_TCP;
ctx->nfs_server.protocol = XPRT_TRANSPORT_TCP;
break;
case Opt_xprt_rdma6:
- protofamily = AF_INET6;
+ ctx->protofamily = AF_INET6;
case Opt_xprt_rdma:
/* vector side protocols to TCP */
ctx->flags |= NFS_MOUNT_TCP;
@@ -773,7 +745,7 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
dfprintk(MOUNT, "NFS: unrecognized "
"transport protocol\n");
kfree(string);
- return 0;
+ return -EINVAL;
}
kfree(string);
break;
@@ -785,15 +757,15 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
nfs_xprt_protocol_tokens, args);
kfree(string);
- mountfamily = AF_INET;
+ ctx->mountfamily = AF_INET;
switch (token) {
case Opt_xprt_udp6:
- mountfamily = AF_INET6;
+ ctx->mountfamily = AF_INET6;
case Opt_xprt_udp:
ctx->mount_server.protocol = XPRT_TRANSPORT_UDP;
break;
case Opt_xprt_tcp6:
- mountfamily = AF_INET6;
+ ctx->mountfamily = AF_INET6;
case Opt_xprt_tcp:
ctx->mount_server.protocol = XPRT_TRANSPORT_TCP;
break;
@@ -801,7 +773,7 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
default:
dfprintk(MOUNT, "NFS: unrecognized "
"transport protocol\n");
- return 0;
+ return -EINVAL;
}
break;
case Opt_addr:
@@ -860,7 +832,7 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
default:
dfprintk(MOUNT, "NFS: invalid "
"lookupcache argument\n");
- return 0;
+ return -EINVAL;
};
break;
case Opt_fscache_uniq:
@@ -893,7 +865,7 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
default:
dfprintk(MOUNT, "NFS: invalid "
"local_lock argument\n");
- return 0;
+ return -EINVAL;
};
break;
@@ -901,7 +873,7 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
* Special options
*/
case Opt_sloppy:
- sloppy = 1;
+ ctx->sloppy = 1;
dfprintk(MOUNT, "NFS: relaxing parsing rules\n");
break;
case Opt_userspace:
@@ -911,12 +883,63 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
break;
default:
- invalid_option = 1;
dfprintk(MOUNT, "NFS: unrecognized mount option "
"'%s'\n", p);
+ return -EINVAL;
}
}
+ return 0;
+
+out_invalid_address:
+ printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
+ return -EINVAL;
+out_invalid_value:
+ printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
+ return -EINVAL;
+out_nomem:
+ printk(KERN_INFO "NFS: not enough memory to parse option\n");
+ return -ENOMEM;
+}
+
+/*
+ * Error-check and convert a string of mount options from user space into
+ * a data structure. The whole mount string is processed; bad options are
+ * skipped as they are encountered. If there were no errors, return 1;
+ * otherwise return 0 (zero).
+ */
+int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
+{
+ char *p, *secdata;
+ int rc, sloppy = 0, invalid_option = 0;
+
+ if (!raw) {
+ dfprintk(MOUNT, "NFS: mount options string was NULL.\n");
+ return 1;
+ }
+ dfprintk(MOUNT, "NFS: nfs mount opts='%s'\n", raw);
+
+ secdata = alloc_secdata();
+ if (!secdata)
+ goto out_nomem;
+
+ rc = security_sb_copy_data(raw, secdata);
+ if (rc)
+ goto out_security_failure;
+
+ rc = security_sb_parse_opts_str(secdata, &ctx->lsm_opts);
+ if (rc)
+ goto out_security_failure;
+
+ free_secdata(secdata);
+
+ while ((p = strsep(&raw, ",")) != NULL) {
+ if (!*p)
+ continue;
+ if (nfs_fs_context_parse_option(ctx, p) < 0)
+ invalid_option = true;
+ }
+
if (!sloppy && invalid_option)
return 0;
@@ -931,22 +954,26 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
* verify that any proto=/mountproto= options match the address
* families in the addr=/mountaddr= options.
*/
- if (protofamily != AF_UNSPEC &&
- protofamily != ctx->nfs_server.address.ss_family)
+ if (ctx->protofamily != AF_UNSPEC &&
+ ctx->protofamily != ctx->nfs_server.address.ss_family)
goto out_proto_mismatch;
- if (mountfamily != AF_UNSPEC) {
+ if (ctx->mountfamily != AF_UNSPEC) {
if (ctx->mount_server.addrlen) {
- if (mountfamily != ctx->mount_server.address.ss_family)
+ if (ctx->mountfamily != ctx->mount_server.address.ss_family)
goto out_mountproto_mismatch;
} else {
- if (mountfamily != ctx->nfs_server.address.ss_family)
+ if (ctx->mountfamily != ctx->nfs_server.address.ss_family)
goto out_mountproto_mismatch;
}
}
return 1;
+out_minorversion_mismatch:
+ printk(KERN_INFO "NFS: mount option vers=%u does not support "
+ "minorversion=%u\n", ctx->version, ctx->minorversion);
+ return 0;
out_mountproto_mismatch:
printk(KERN_INFO "NFS: mount server address does not match mountproto= "
"option\n");
@@ -954,20 +981,10 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
out_proto_mismatch:
printk(KERN_INFO "NFS: server address does not match proto= option\n");
return 0;
-out_invalid_address:
- printk(KERN_INFO "NFS: bad IP address specified: %s\n", p);
- return 0;
-out_invalid_value:
- printk(KERN_INFO "NFS: bad mount option value specified: %s\n", p);
- return 0;
-out_minorversion_mismatch:
- printk(KERN_INFO "NFS: mount option vers=%u does not support "
- "minorversion=%u\n", ctx->version, ctx->minorversion);
- return 0;
out_migration_misuse:
printk(KERN_INFO
"NFS: 'migration' not supported for this NFS version\n");
- return 0;
+ return -EINVAL;
out_nomem:
printk(KERN_INFO "NFS: not enough memory to parse option\n");
return 0;
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 990e0d4d59fa..fab0fca9e0ef 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -100,7 +100,10 @@ struct nfs_fs_context {
unsigned int version;
unsigned int minorversion;
char *fscache_uniq;
+ unsigned short protofamily;
+ unsigned short mountfamily;
bool need_mount;
+ bool sloppy;
struct {
struct sockaddr_storage address;
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 03/27] VFS: Make get_mnt_ns() return the namespace [ver #5] |
| Message-ID | <tSifo-6QJ-31@gated-at.bofh.it> |
| In reply to | #1665947 |
Make get_mnt_ns() return the namespace it got a ref on for consistency with
other namespace ref getting functions.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/mount.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/mount.h b/fs/mount.h
index bf1fda6eed8f..02ef292a77d7 100644
--- a/fs/mount.h
+++ b/fs/mount.h
@@ -108,9 +108,10 @@ static inline void detach_mounts(struct dentry *dentry)
__detach_mounts(dentry);
}
-static inline void get_mnt_ns(struct mnt_namespace *ns)
+static inline struct mnt_namespace *get_mnt_ns(struct mnt_namespace *ns)
{
atomic_inc(&ns->count);
+ return ns;
}
extern seqlock_t mount_lock;
[toc] | [prev] | [next] | [standalone]
| From | Al Viro <viro@ZenIV.linux.org.uk> |
|---|---|
| Date | 2017-06-15 11:20 +0200 |
| Subject | Re: [PATCH 03/27] VFS: Make get_mnt_ns() return the namespace [ver #5] |
| Message-ID | <tSz6x-C2-5@gated-at.bofh.it> |
| In reply to | #1665952 |
On Wed, Jun 14, 2017 at 04:15:42PM +0100, David Howells wrote: > Make get_mnt_ns() return the namespace it got a ref on for consistency with > other namespace ref getting functions. Is there any point in doing that? I mean, it's not used in your patchset anymore and existing callers are a mixed bag...
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 27/27] kernfs, sysfs, cgroup: Support fs_context [ver #5] |
| Message-ID | <tSifo-6QJ-17@gated-at.bofh.it> |
| In reply to | #1665947 |
Make kernfs support superblock creation/mount/remount with fs_context.
This requires that sysfs and cgroup, which are built on kernfs, be made to
support fs_context also.
Notes:
(1) A kernfs_fs_context struct is created to wrap fs_context and the
kernfs mount parameters are moved in here (or are in fs_context).
(2) kernfs_mount{,_ns}() are made into kernfs_get_tree(). The extra
namespace tag parameter is passed in the context if desired
(3) kernfs_free_fs_context() is provided as a destructor for the
kernfs_fs_context struct, but for the moment it does nothing except
get called in the right places.
(4) sysfs doesn't wrap kernfs_fs_context since it has no parameters to
pass, but possibly this should be done anyway in case someone wants to
add a parameter in future.
(5) A cgroup_fs_context struct is created to wrap kernfs_fs_context and
the cgroup v1 and v2 mount parameters are all moved there.
(6) cgroup1 parameter parsing error messages are now handled by invalf(),
which allows userspace to collect them directly.
(7) cgroup1 parameter cleanup is now done in the context destructor rather
than in the mount/get_tree and remount functions.
Weirdies:
(*) cgroup_do_get_tree() calls cset_cgroup_from_root() with locks held,
but then uses the resulting pointer after dropping the locks. I'm
told this is okay and needs commenting.
(*) The cgroup refcount web. This really needs documenting.
(*) cgroup2 only has one root?
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
cc: Tejun Heo <tj@kernel.org>
cc: Li Zefan <lizefan@huawei.com>
cc: Johannes Weiner <hannes@cmpxchg.org>
cc: cgroups@vger.kernel.org
---
fs/kernfs/mount.c | 88 ++++++------
fs/sysfs/mount.c | 59 +++++---
include/linux/cgroup.h | 3
include/linux/kernfs.h | 37 +++--
kernel/cgroup/cgroup-internal.h | 42 +++---
kernel/cgroup/cgroup-v1.c | 291 ++++++++++++++++++---------------------
kernel/cgroup/cgroup.c | 172 +++++++++++++++--------
7 files changed, 383 insertions(+), 309 deletions(-)
diff --git a/fs/kernfs/mount.c b/fs/kernfs/mount.c
index f1e0b15015b7..4391e68e9cac 100644
--- a/fs/kernfs/mount.c
+++ b/fs/kernfs/mount.c
@@ -21,13 +21,14 @@
struct kmem_cache *kernfs_node_cache;
-static int kernfs_sop_remount_fs(struct super_block *sb, int *flags, char *data)
+static int kernfs_sop_remount_fs(struct super_block *sb, struct fs_context *fc)
{
+ struct kernfs_fs_context *kfc = container_of(fc, struct kernfs_fs_context, fc);
struct kernfs_root *root = kernfs_info(sb)->root;
struct kernfs_syscall_ops *scops = root->syscall_ops;
if (scops && scops->remount_fs)
- return scops->remount_fs(root, flags, data);
+ return scops->remount_fs(root, kfc);
return 0;
}
@@ -59,7 +60,7 @@ const struct super_operations kernfs_sops = {
.drop_inode = generic_delete_inode,
.evict_inode = kernfs_evict_inode,
- .remount_fs = kernfs_sop_remount_fs,
+ .remount_fs_fc = kernfs_sop_remount_fs,
.show_options = kernfs_sop_show_options,
.show_path = kernfs_sop_show_path,
};
@@ -145,7 +146,7 @@ struct dentry *kernfs_node_dentry(struct kernfs_node *kn,
} while (true);
}
-static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
+static int kernfs_fill_super(struct super_block *sb, struct kernfs_fs_context *kfc)
{
struct kernfs_super_info *info = kernfs_info(sb);
struct inode *inode;
@@ -156,7 +157,7 @@ static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
sb->s_iflags |= SB_I_NOEXEC | SB_I_NODEV;
sb->s_blocksize = PAGE_SIZE;
sb->s_blocksize_bits = PAGE_SHIFT;
- sb->s_magic = magic;
+ sb->s_magic = kfc->magic;
sb->s_op = &kernfs_sops;
sb->s_xattr = kernfs_xattr_handlers;
sb->s_time_gran = 1;
@@ -183,20 +184,25 @@ static int kernfs_fill_super(struct super_block *sb, unsigned long magic)
return 0;
}
-static int kernfs_test_super(struct super_block *sb, void *data)
+static int kernfs_test_super(struct super_block *sb, struct fs_context *fc)
{
+ struct kernfs_fs_context *kfc = container_of(fc, struct kernfs_fs_context, fc);
struct kernfs_super_info *sb_info = kernfs_info(sb);
- struct kernfs_super_info *info = data;
+ struct kernfs_super_info *info = kfc->info;
return sb_info->root == info->root && sb_info->ns == info->ns;
}
-static int kernfs_set_super(struct super_block *sb, void *data)
+static int kernfs_set_super(struct super_block *sb, struct fs_context *fc)
{
+ struct kernfs_fs_context *kfc = container_of(fc, struct kernfs_fs_context, fc);
int error;
- error = set_anon_super(sb, data);
- if (!error)
- sb->s_fs_info = data;
+
+ error = set_anon_super(sb, kfc->info);
+ if (!error) {
+ sb->s_fs_info = kfc->info;
+ kfc->info = NULL;
+ }
return error;
}
@@ -214,24 +220,15 @@ const void *kernfs_super_ns(struct super_block *sb)
}
/**
- * kernfs_mount_ns - kernfs mount helper
- * @fs_type: file_system_type of the fs being mounted
- * @flags: mount flags specified for the mount
- * @root: kernfs_root of the hierarchy being mounted
- * @magic: file system specific magic number
- * @new_sb_created: tell the caller if we allocated a new superblock
- * @ns: optional namespace tag of the mount
- *
- * This is to be called from each kernfs user's file_system_type->mount()
- * implementation, which should pass through the specified @fs_type and
- * @flags, and specify the hierarchy and namespace tag to mount via @root
- * and @ns, respectively.
+ * kernfs_get_tree - kernfs filesystem access/retrieval helper
+ * @kfc: The filesystem context.
*
- * The return value can be passed to the vfs layer verbatim.
+ * This is to be called from each kernfs user's fs_context->ops->get_tree()
+ * implementation, which should set the specified ->@fs_type and ->@flags, and
+ * specify the hierarchy and namespace tag to mount via ->@root and ->@ns,
+ * respectively.
*/
-struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
- struct kernfs_root *root, unsigned long magic,
- bool *new_sb_created, const void *ns)
+int kernfs_get_tree(struct kernfs_fs_context *kfc)
{
struct super_block *sb;
struct kernfs_super_info *info;
@@ -239,37 +236,42 @@ struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
info = kzalloc(sizeof(*info), GFP_KERNEL);
if (!info)
- return ERR_PTR(-ENOMEM);
-
- info->root = root;
- info->ns = ns;
+ return -ENOMEM;
- sb = sget_userns(fs_type, kernfs_test_super, kernfs_set_super, flags,
- &init_user_ns, info);
- if (IS_ERR(sb) || sb->s_fs_info != info)
- kfree(info);
+ info->root = kfc->root;
+ info->ns = kfc->ns_tag;
+
+ kfc->info = info;
+ sb = sget_fc(&kfc->fc, kernfs_test_super, kernfs_set_super);
+ if (kfc->info) {
+ kfree(kfc->info);
+ kfc->info = NULL;
+ } else {
+ kfc->ns_tag = NULL;
+ kfc->fc.degraded = true;
+ }
if (IS_ERR(sb))
- return ERR_CAST(sb);
-
- if (new_sb_created)
- *new_sb_created = !sb->s_root;
+ return PTR_ERR(sb);
if (!sb->s_root) {
struct kernfs_super_info *info = kernfs_info(sb);
- error = kernfs_fill_super(sb, magic);
+ kfc->new_sb_created = true;
+
+ error = kernfs_fill_super(sb, kfc);
if (error) {
deactivate_locked_super(sb);
- return ERR_PTR(error);
+ return error;
}
sb->s_flags |= SB_ACTIVE;
mutex_lock(&kernfs_mutex);
- list_add(&info->node, &root->supers);
+ list_add(&info->node, &info->root->supers);
mutex_unlock(&kernfs_mutex);
}
- return dget(sb->s_root);
+ kfc->fc.root = dget(sb->s_root);
+ return 0;
}
/**
diff --git a/fs/sysfs/mount.c b/fs/sysfs/mount.c
index fb49510c5dcf..cfe900d43663 100644
--- a/fs/sysfs/mount.c
+++ b/fs/sysfs/mount.c
@@ -23,27 +23,45 @@
static struct kernfs_root *sysfs_root;
struct kernfs_node *sysfs_root_kn;
-static struct dentry *sysfs_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int sysfs_get_tree(struct fs_context *fc)
{
- struct dentry *root;
- void *ns;
- bool new_sb;
+ struct kernfs_fs_context *kfc = container_of(fc, struct kernfs_fs_context, fc);
+ int ret;
- if (!(flags & SB_KERNMOUNT)) {
+ ret = kernfs_get_tree(kfc);
+ if (kfc->new_sb_created)
+ fc->root->d_sb->s_iflags |= SB_I_USERNS_VISIBLE;
+ return 0;
+}
+
+static void sysfs_fs_context_free(struct fs_context *fc)
+{
+ struct kernfs_fs_context *kfc = container_of(fc, struct kernfs_fs_context, fc);
+
+ if (kfc->ns_tag)
+ kobj_ns_drop(KOBJ_NS_TYPE_NET, kfc->ns_tag);
+ kernfs_free_fs_context(kfc);
+}
+
+static const struct fs_context_operations sysfs_fs_context_ops = {
+ .free = sysfs_fs_context_free,
+ .get_tree = sysfs_get_tree,
+};
+
+static int sysfs_init_fs_context(struct fs_context *fc, struct super_block *src_sb)
+{
+ struct kernfs_fs_context *kfc = container_of(fc, struct kernfs_fs_context, fc);
+
+ if (!(fc->sb_flags & SB_KERNMOUNT)) {
if (!kobj_ns_current_may_mount(KOBJ_NS_TYPE_NET))
- return ERR_PTR(-EPERM);
+ return -EPERM;
}
- ns = kobj_ns_grab_current(KOBJ_NS_TYPE_NET);
- root = kernfs_mount_ns(fs_type, flags, sysfs_root,
- SYSFS_MAGIC, &new_sb, ns);
- if (IS_ERR(root) || !new_sb)
- kobj_ns_drop(KOBJ_NS_TYPE_NET, ns);
- else if (new_sb)
- root->d_sb->s_iflags |= SB_I_USERNS_VISIBLE;
-
- return root;
+ kfc->ns_tag = kobj_ns_grab_current(KOBJ_NS_TYPE_NET);
+ kfc->root = sysfs_root;
+ kfc->magic = SYSFS_MAGIC;
+ kfc->fc.ops = &sysfs_fs_context_ops;
+ return 0;
}
static void sysfs_kill_sb(struct super_block *sb)
@@ -55,10 +73,11 @@ static void sysfs_kill_sb(struct super_block *sb)
}
static struct file_system_type sysfs_fs_type = {
- .name = "sysfs",
- .mount = sysfs_mount,
- .kill_sb = sysfs_kill_sb,
- .fs_flags = FS_USERNS_MOUNT,
+ .name = "sysfs",
+ .fs_context_size = sizeof(struct kernfs_fs_context),
+ .init_fs_context = sysfs_init_fs_context,
+ .kill_sb = sysfs_kill_sb,
+ .fs_flags = FS_USERNS_MOUNT,
};
int __init sysfs_init(void)
diff --git a/include/linux/cgroup.h b/include/linux/cgroup.h
index 710a005c6b7a..d5b5d9ae373c 100644
--- a/include/linux/cgroup.h
+++ b/include/linux/cgroup.h
@@ -713,10 +713,11 @@ copy_cgroup_ns(unsigned long flags, struct user_namespace *user_ns,
#endif /* !CONFIG_CGROUPS */
-static inline void get_cgroup_ns(struct cgroup_namespace *ns)
+static inline struct cgroup_namespace *get_cgroup_ns(struct cgroup_namespace *ns)
{
if (ns)
refcount_inc(&ns->count);
+ return ns;
}
static inline void put_cgroup_ns(struct cgroup_namespace *ns)
diff --git a/include/linux/kernfs.h b/include/linux/kernfs.h
index a9b11b8d06f2..c137eef5b31f 100644
--- a/include/linux/kernfs.h
+++ b/include/linux/kernfs.h
@@ -16,6 +16,7 @@
#include <linux/rbtree.h>
#include <linux/atomic.h>
#include <linux/wait.h>
+#include <linux/fs_context.h>
struct file;
struct dentry;
@@ -25,6 +26,7 @@ struct vm_area_struct;
struct super_block;
struct file_system_type;
+struct kernfs_fs_context;
struct kernfs_open_node;
struct kernfs_iattrs;
@@ -145,7 +147,7 @@ struct kernfs_node {
* kernfs_node parameter.
*/
struct kernfs_syscall_ops {
- int (*remount_fs)(struct kernfs_root *root, int *flags, char *data);
+ int (*remount_fs)(struct kernfs_root *root, struct kernfs_fs_context *kfc);
int (*show_options)(struct seq_file *sf, struct kernfs_root *root);
int (*mkdir)(struct kernfs_node *parent, const char *name,
@@ -245,6 +247,20 @@ struct kernfs_ops {
#endif
};
+/*
+ * The kernfs superblock creation/mount parameter context.
+ */
+struct kernfs_fs_context {
+ struct fs_context fc;
+ struct kernfs_root *root; /* Root of the hierarchy being mounted */
+ void *ns_tag; /* Namespace tag of the mount (or NULL) */
+ unsigned long magic; /* File system specific magic number */
+
+ /* The following are set/used by kernfs_mount() */
+ struct kernfs_super_info *info; /* The new superblock info */
+ bool new_sb_created; /* Set to T if we allocated a new sb */
+};
+
#ifdef CONFIG_KERNFS
static inline enum kernfs_node_type kernfs_type(struct kernfs_node *kn)
@@ -328,9 +344,7 @@ int kernfs_setattr(struct kernfs_node *kn, const struct iattr *iattr);
void kernfs_notify(struct kernfs_node *kn);
const void *kernfs_super_ns(struct super_block *sb);
-struct dentry *kernfs_mount_ns(struct file_system_type *fs_type, int flags,
- struct kernfs_root *root, unsigned long magic,
- bool *new_sb_created, const void *ns);
+int kernfs_get_tree(struct kernfs_fs_context *fc);
void kernfs_kill_sb(struct super_block *sb);
struct super_block *kernfs_pin_sb(struct kernfs_root *root, const void *ns);
@@ -430,11 +444,8 @@ static inline void kernfs_notify(struct kernfs_node *kn) { }
static inline const void *kernfs_super_ns(struct super_block *sb)
{ return NULL; }
-static inline struct dentry *
-kernfs_mount_ns(struct file_system_type *fs_type, int flags,
- struct kernfs_root *root, unsigned long magic,
- bool *new_sb_created, const void *ns)
-{ return ERR_PTR(-ENOSYS); }
+static inline int kernfs_get_tree(struct kernfs_fs_context *fc)
+{ return -ENOSYS; }
static inline void kernfs_kill_sb(struct super_block *sb) { }
@@ -511,13 +522,9 @@ static inline int kernfs_rename(struct kernfs_node *kn,
return kernfs_rename_ns(kn, new_parent, new_name, NULL);
}
-static inline struct dentry *
-kernfs_mount(struct file_system_type *fs_type, int flags,
- struct kernfs_root *root, unsigned long magic,
- bool *new_sb_created)
+static inline void kernfs_free_fs_context(struct kernfs_fs_context *kfc)
{
- return kernfs_mount_ns(fs_type, flags, root,
- magic, new_sb_created, NULL);
+ /* Note that we don't deal with kfc->ns_tag here. */
}
#endif /* __LINUX_KERNFS_H */
diff --git a/kernel/cgroup/cgroup-internal.h b/kernel/cgroup/cgroup-internal.h
index 00f4d6bf048f..a74e5f0d523a 100644
--- a/kernel/cgroup/cgroup-internal.h
+++ b/kernel/cgroup/cgroup-internal.h
@@ -8,6 +8,26 @@
#include <linux/refcount.h>
/*
+ * The cgroup filesystem superblock creation/mount context.
+ */
+struct cgroup_fs_context {
+ struct kernfs_fs_context kfc;
+ struct cgroup_root *root;
+ struct cgroup_namespace *ns;
+ u8 version; /* cgroups version */
+
+ /* cgroup1 bits */
+ bool cpuset_clone_children;
+ bool none; /* User explicitly requested empty subsystem */
+ bool all_ss; /* Seen 'all' option */
+ bool one_ss; /* Seen 'none' option */
+ u16 subsys_mask; /* Selected subsystems */
+ unsigned int flags; /* CGRP_ROOT_* flags */
+ char *name; /* Hierarchy name */
+ char *release_agent; /* Path for release notifications */
+};
+
+/*
* A cgroup can be associated with multiple css_sets as different tasks may
* belong to different cgroups on different hierarchies. In the other
* direction, a css_set is naturally associated with multiple cgroups.
@@ -85,16 +105,6 @@ struct cgroup_mgctx {
#define DEFINE_CGROUP_MGCTX(name) \
struct cgroup_mgctx name = CGROUP_MGCTX_INIT(name)
-struct cgroup_sb_opts {
- u16 subsys_mask;
- unsigned int flags;
- char *release_agent;
- bool cpuset_clone_children;
- char *name;
- /* User explicitly requested empty subsystem */
- bool none;
-};
-
extern struct mutex cgroup_mutex;
extern spinlock_t css_set_lock;
extern struct cgroup_subsys *cgroup_subsys[];
@@ -163,12 +173,10 @@ int cgroup_path_ns_locked(struct cgroup *cgrp, char *buf, size_t buflen,
struct cgroup_namespace *ns);
void cgroup_free_root(struct cgroup_root *root);
-void init_cgroup_root(struct cgroup_root *root, struct cgroup_sb_opts *opts);
+void init_cgroup_root(struct cgroup_fs_context *ctx);
int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask, int ref_flags);
int rebind_subsystems(struct cgroup_root *dst_root, u16 ss_mask);
-struct dentry *cgroup_do_mount(struct file_system_type *fs_type, int flags,
- struct cgroup_root *root, unsigned long magic,
- struct cgroup_namespace *ns);
+int cgroup_do_get_tree(struct cgroup_fs_context *ctx);
bool cgroup_may_migrate_to(struct cgroup *dst_cgrp);
void cgroup_migrate_finish(struct cgroup_mgctx *mgctx);
@@ -208,8 +216,8 @@ bool cgroup1_ssid_disabled(int ssid);
void cgroup1_pidlist_destroy_all(struct cgroup *cgrp);
void cgroup1_release_agent(struct work_struct *work);
void cgroup1_check_for_release(struct cgroup *cgrp);
-struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
- void *data, unsigned long magic,
- struct cgroup_namespace *ns);
+int cgroup1_parse_option(struct cgroup_fs_context *ctx, char *p);
+int cgroup1_validate(struct cgroup_fs_context *ctx);
+int cgroup1_get_tree(struct cgroup_fs_context *ctx);
#endif /* __CGROUP_INTERNAL_H */
diff --git a/kernel/cgroup/cgroup-v1.c b/kernel/cgroup/cgroup-v1.c
index 85d75152402d..050d4a0e8e5a 100644
--- a/kernel/cgroup/cgroup-v1.c
+++ b/kernel/cgroup/cgroup-v1.c
@@ -864,164 +864,160 @@ static int cgroup1_show_options(struct seq_file *seq, struct kernfs_root *kf_roo
return 0;
}
-static int parse_cgroupfs_options(char *data, struct cgroup_sb_opts *opts)
+int cgroup1_parse_option(struct cgroup_fs_context *ctx, char *token)
{
- char *token, *o = data;
- bool all_ss = false, one_ss = false;
- u16 mask = U16_MAX;
struct cgroup_subsys *ss;
- int nr_opts = 0;
int i;
-#ifdef CONFIG_CPUSETS
- mask = ~((u16)1 << cpuset_cgrp_id);
-#endif
-
- memset(opts, 0, sizeof(*opts));
-
- while ((token = strsep(&o, ",")) != NULL) {
- nr_opts++;
+ if (!strcmp(token, "none")) {
+ /* Explicitly have no subsystems */
+ ctx->none = true;
+ return 0;
+ }
+ if (!strcmp(token, "all")) {
+ /* Mutually exclusive option 'all' + subsystem name */
+ if (ctx->one_ss)
+ return invalf("cgroup1: all conflicts with subsys name");
+ ctx->all_ss = true;
+ return 0;
+ }
+ if (!strcmp(token, "noprefix")) {
+ ctx->flags |= CGRP_ROOT_NOPREFIX;
+ return 0;
+ }
+ if (!strcmp(token, "clone_children")) {
+ ctx->cpuset_clone_children = true;
+ return 0;
+ }
+ if (!strcmp(token, "xattr")) {
+ ctx->flags |= CGRP_ROOT_XATTR;
+ return 0;
+ }
+ if (!strncmp(token, "release_agent=", 14)) {
+ /* Specifying two release agents is forbidden */
+ if (ctx->release_agent)
+ return invalf("cgroup1: release_agent respecified");
+ ctx->release_agent =
+ kstrndup(token + 14, PATH_MAX - 1, GFP_KERNEL);
+ if (!ctx->release_agent)
+ return -ENOMEM;
+ return 0;
+ }
- if (!*token)
- return -EINVAL;
- if (!strcmp(token, "none")) {
- /* Explicitly have no subsystems */
- opts->none = true;
- continue;
- }
- if (!strcmp(token, "all")) {
- /* Mutually exclusive option 'all' + subsystem name */
- if (one_ss)
- return -EINVAL;
- all_ss = true;
- continue;
- }
- if (!strcmp(token, "noprefix")) {
- opts->flags |= CGRP_ROOT_NOPREFIX;
- continue;
+ if (!strncmp(token, "name=", 5)) {
+ const char *name = token + 5;
+ /* Can't specify an empty name */
+ if (!strlen(name))
+ return invalf("cgroup1: Empty name");
+ /* Must match [\w.-]+ */
+ for (i = 0; i < strlen(name); i++) {
+ char c = name[i];
+ if (isalnum(c))
+ continue;
+ if ((c == '.') || (c == '-') || (c == '_'))
+ continue;
+ return invalf("cgroup1: Invalid name");
}
- if (!strcmp(token, "clone_children")) {
- opts->cpuset_clone_children = true;
+ /* Specifying two names is forbidden */
+ if (ctx->name)
+ return invalf("cgroup1: name respecified");
+ ctx->name = kstrndup(name,
+ MAX_CGROUP_ROOT_NAMELEN - 1,
+ GFP_KERNEL);
+ if (!ctx->name)
+ return -ENOMEM;
+
+ return 0;
+ }
+
+ for_each_subsys(ss, i) {
+ if (strcmp(token, ss->legacy_name))
continue;
- }
- if (!strcmp(token, "xattr")) {
- opts->flags |= CGRP_ROOT_XATTR;
+ if (!cgroup_ssid_enabled(i))
continue;
- }
- if (!strncmp(token, "release_agent=", 14)) {
- /* Specifying two release agents is forbidden */
- if (opts->release_agent)
- return -EINVAL;
- opts->release_agent =
- kstrndup(token + 14, PATH_MAX - 1, GFP_KERNEL);
- if (!opts->release_agent)
- return -ENOMEM;
+ if (cgroup1_ssid_disabled(i))
continue;
- }
- if (!strncmp(token, "name=", 5)) {
- const char *name = token + 5;
- /* Can't specify an empty name */
- if (!strlen(name))
- return -EINVAL;
- /* Must match [\w.-]+ */
- for (i = 0; i < strlen(name); i++) {
- char c = name[i];
- if (isalnum(c))
- continue;
- if ((c == '.') || (c == '-') || (c == '_'))
- continue;
- return -EINVAL;
- }
- /* Specifying two names is forbidden */
- if (opts->name)
- return -EINVAL;
- opts->name = kstrndup(name,
- MAX_CGROUP_ROOT_NAMELEN - 1,
- GFP_KERNEL);
- if (!opts->name)
- return -ENOMEM;
- continue;
- }
+ /* Mutually exclusive option 'all' + subsystem name */
+ if (ctx->all_ss)
+ return invalf("cgroup1: subsys name conflicts with all");
+ ctx->subsys_mask |= (1 << i);
+ ctx->one_ss = true;
+ return 0;
+ }
- for_each_subsys(ss, i) {
- if (strcmp(token, ss->legacy_name))
- continue;
- if (!cgroup_ssid_enabled(i))
- continue;
- if (cgroup1_ssid_disabled(i))
- continue;
+ if (i == CGROUP_SUBSYS_COUNT)
+ return -ENOENT;
+
+ return 0;
+}
- /* Mutually exclusive option 'all' + subsystem name */
- if (all_ss)
- return -EINVAL;
- opts->subsys_mask |= (1 << i);
- one_ss = true;
+/*
+ * Validate the options that have been parsed.
+ */
+int cgroup1_validate(struct cgroup_fs_context *ctx)
+{
+ struct cgroup_subsys *ss;
+ u16 mask = U16_MAX;
+ int i;
- break;
- }
- if (i == CGROUP_SUBSYS_COUNT)
- return -ENOENT;
- }
+#ifdef CONFIG_CPUSETS
+ mask = ~((u16)1 << cpuset_cgrp_id);
+#endif
/*
* If the 'all' option was specified select all the subsystems,
* otherwise if 'none', 'name=' and a subsystem name options were
* not specified, let's default to 'all'
*/
- if (all_ss || (!one_ss && !opts->none && !opts->name))
+ if (ctx->all_ss || (!ctx->one_ss && !ctx->none && !ctx->name))
for_each_subsys(ss, i)
if (cgroup_ssid_enabled(i) && !cgroup1_ssid_disabled(i))
- opts->subsys_mask |= (1 << i);
+ ctx->subsys_mask |= (1 << i);
/*
* We either have to specify by name or by subsystems. (So all
* empty hierarchies must have a name).
*/
- if (!opts->subsys_mask && !opts->name)
- return -EINVAL;
+ if (!ctx->subsys_mask && !ctx->name)
+ return invalf("cgroup1: Need name or subsystem set");
/*
* Option noprefix was introduced just for backward compatibility
* with the old cpuset, so we allow noprefix only if mounting just
* the cpuset subsystem.
*/
- if ((opts->flags & CGRP_ROOT_NOPREFIX) && (opts->subsys_mask & mask))
- return -EINVAL;
+ if ((ctx->flags & CGRP_ROOT_NOPREFIX) && (ctx->subsys_mask & mask))
+ return invalf("cgroup1: noprefix used incorrectly");
/* Can't specify "none" and some subsystems */
- if (opts->subsys_mask && opts->none)
- return -EINVAL;
+ if (ctx->subsys_mask && ctx->none)
+ return invalf("cgroup1: none used incorrectly");
return 0;
}
-static int cgroup1_remount(struct kernfs_root *kf_root, int *flags, char *data)
+static int cgroup1_remount(struct kernfs_root *kf_root, struct kernfs_fs_context *kfc)
{
- int ret = 0;
+ struct cgroup_fs_context *ctx = container_of(kfc, struct cgroup_fs_context, kfc);
struct cgroup_root *root = cgroup_root_from_kf(kf_root);
- struct cgroup_sb_opts opts;
u16 added_mask, removed_mask;
+ int ret = 0;
cgroup_lock_and_drain_offline(&cgrp_dfl_root.cgrp);
- /* See what subsystems are wanted */
- ret = parse_cgroupfs_options(data, &opts);
- if (ret)
- goto out_unlock;
-
- if (opts.subsys_mask != root->subsys_mask || opts.release_agent)
+ if (ctx->subsys_mask != root->subsys_mask || ctx->release_agent)
pr_warn("option changes via remount are deprecated (pid=%d comm=%s)\n",
task_tgid_nr(current), current->comm);
- added_mask = opts.subsys_mask & ~root->subsys_mask;
- removed_mask = root->subsys_mask & ~opts.subsys_mask;
+ added_mask = ctx->subsys_mask & ~root->subsys_mask;
+ removed_mask = root->subsys_mask & ~ctx->subsys_mask;
/* Don't allow flags or name to change at remount */
- if ((opts.flags ^ root->flags) ||
- (opts.name && strcmp(opts.name, root->name))) {
- pr_err("option or name mismatch, new: 0x%x \"%s\", old: 0x%x \"%s\"\n",
- opts.flags, opts.name ?: "", root->flags, root->name);
+ if ((ctx->flags ^ root->flags) ||
+ (ctx->name && strcmp(ctx->name, root->name))) {
+ invalf("option or name mismatch, new: 0x%x \"%s\", old: 0x%x \"%s\"",
+ ctx->flags, ctx->name ?: "", root->flags, root->name);
ret = -EINVAL;
goto out_unlock;
}
@@ -1038,17 +1034,15 @@ static int cgroup1_remount(struct kernfs_root *kf_root, int *flags, char *data)
WARN_ON(rebind_subsystems(&cgrp_dfl_root, removed_mask));
- if (opts.release_agent) {
+ if (ctx->release_agent) {
spin_lock(&release_agent_path_lock);
- strcpy(root->release_agent_path, opts.release_agent);
+ strcpy(root->release_agent_path, ctx->release_agent);
spin_unlock(&release_agent_path_lock);
}
trace_cgroup_remount(root);
out_unlock:
- kfree(opts.release_agent);
- kfree(opts.name);
mutex_unlock(&cgroup_mutex);
return ret;
}
@@ -1062,25 +1056,19 @@ struct kernfs_syscall_ops cgroup1_kf_syscall_ops = {
.show_path = cgroup_show_path,
};
-struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
- void *data, unsigned long magic,
- struct cgroup_namespace *ns)
+/*
+ * Find or create a v1 cgroups superblock.
+ */
+int cgroup1_get_tree(struct cgroup_fs_context *ctx)
{
struct super_block *pinned_sb = NULL;
- struct cgroup_sb_opts opts;
struct cgroup_root *root;
struct cgroup_subsys *ss;
- struct dentry *dentry;
int i, ret;
bool new_root = false;
cgroup_lock_and_drain_offline(&cgrp_dfl_root.cgrp);
- /* First find the desired set of subsystems */
- ret = parse_cgroupfs_options(data, &opts);
- if (ret)
- goto out_unlock;
-
/*
* Destruction of cgroup root is asynchronous, so subsystems may
* still be dying after the previous unmount. Let's drain the
@@ -1089,15 +1077,13 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
* starting. Testing ref liveliness is good enough.
*/
for_each_subsys(ss, i) {
- if (!(opts.subsys_mask & (1 << i)) ||
+ if (!(ctx->subsys_mask & (1 << i)) ||
ss->root == &cgrp_dfl_root)
continue;
if (!percpu_ref_tryget_live(&ss->root->cgrp.self.refcnt)) {
mutex_unlock(&cgroup_mutex);
- msleep(10);
- ret = restart_syscall();
- goto out_free;
+ goto err_restart;
}
cgroup_put(&ss->root->cgrp);
}
@@ -1113,8 +1099,8 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
* name matches but sybsys_mask doesn't, we should fail.
* Remember whether name matched.
*/
- if (opts.name) {
- if (strcmp(opts.name, root->name))
+ if (ctx->name) {
+ if (strcmp(ctx->name, root->name))
continue;
name_match = true;
}
@@ -1123,15 +1109,15 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
* If we asked for subsystems (or explicitly for no
* subsystems) then they must match.
*/
- if ((opts.subsys_mask || opts.none) &&
- (opts.subsys_mask != root->subsys_mask)) {
+ if ((ctx->subsys_mask || ctx->none) &&
+ (ctx->subsys_mask != root->subsys_mask)) {
if (!name_match)
continue;
ret = -EBUSY;
- goto out_unlock;
+ goto err_unlock;
}
- if (root->flags ^ opts.flags)
+ if (root->flags ^ ctx->flags)
pr_warn("new mount options do not match the existing superblock, will be ignored\n");
/*
@@ -1152,9 +1138,7 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
mutex_unlock(&cgroup_mutex);
if (!IS_ERR_OR_NULL(pinned_sb))
deactivate_super(pinned_sb);
- msleep(10);
- ret = restart_syscall();
- goto out_free;
+ goto err_restart;
}
ret = 0;
@@ -1166,41 +1150,35 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
* specification is allowed for already existing hierarchies but we
* can't create new one without subsys specification.
*/
- if (!opts.subsys_mask && !opts.none) {
- ret = -EINVAL;
- goto out_unlock;
+ if (!ctx->subsys_mask && !ctx->none) {
+ ret = invalf("cgroup1: No subsys list or none specified");
+ goto err_unlock;
}
/* Hierarchies may only be created in the initial cgroup namespace. */
- if (ns != &init_cgroup_ns) {
+ if (ctx->ns != &init_cgroup_ns) {
ret = -EPERM;
- goto out_unlock;
+ goto err_unlock;
}
root = kzalloc(sizeof(*root), GFP_KERNEL);
if (!root) {
ret = -ENOMEM;
- goto out_unlock;
+ goto err_unlock;
}
new_root = true;
+ ctx->root = root;
- init_cgroup_root(root, &opts);
+ init_cgroup_root(ctx);
- ret = cgroup_setup_root(root, opts.subsys_mask, PERCPU_REF_INIT_DEAD);
+ ret = cgroup_setup_root(root, ctx->subsys_mask, PERCPU_REF_INIT_DEAD);
if (ret)
cgroup_free_root(root);
out_unlock:
mutex_unlock(&cgroup_mutex);
-out_free:
- kfree(opts.release_agent);
- kfree(opts.name);
-
- if (ret)
- return ERR_PTR(ret);
- dentry = cgroup_do_mount(&cgroup_fs_type, flags, root,
- CGROUP_SUPER_MAGIC, ns);
+ ret = cgroup_do_get_tree(ctx);
/*
* There's a race window after we release cgroup_mutex and before
@@ -1221,7 +1199,14 @@ struct dentry *cgroup1_mount(struct file_system_type *fs_type, int flags,
if (pinned_sb)
deactivate_super(pinned_sb);
- return dentry;
+ return ret;
+
+err_restart:
+ msleep(10);
+ return restart_syscall();
+err_unlock:
+ mutex_unlock(&cgroup_mutex);
+ return ret;
}
static int __init cgroup1_wq_init(void)
diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c
index 8d4e85eae42c..4cbf8ef26577 100644
--- a/kernel/cgroup/cgroup.c
+++ b/kernel/cgroup/cgroup.c
@@ -1542,10 +1542,9 @@ int cgroup_show_path(struct seq_file *sf, struct kernfs_node *kf_node,
return len;
}
-static int cgroup_remount(struct kernfs_root *kf_root, int *flags, char *data)
+static int cgroup_remount(struct kernfs_root *kf_root, struct kernfs_fs_context *kfc)
{
- pr_err("remount is not allowed\n");
- return -EINVAL;
+ return invalf("cgroup2: Remount is not allowed");
}
/*
@@ -1626,8 +1625,9 @@ static void init_cgroup_housekeeping(struct cgroup *cgrp)
INIT_WORK(&cgrp->release_agent_work, cgroup1_release_agent);
}
-void init_cgroup_root(struct cgroup_root *root, struct cgroup_sb_opts *opts)
+void init_cgroup_root(struct cgroup_fs_context *ctx)
{
+ struct cgroup_root *root = ctx->root;
struct cgroup *cgrp = &root->cgrp;
INIT_LIST_HEAD(&root->root_list);
@@ -1636,12 +1636,12 @@ void init_cgroup_root(struct cgroup_root *root, struct cgroup_sb_opts *opts)
init_cgroup_housekeeping(cgrp);
idr_init(&root->cgroup_idr);
- root->flags = opts->flags;
- if (opts->release_agent)
- strcpy(root->release_agent_path, opts->release_agent);
- if (opts->name)
- strcpy(root->name, opts->name);
- if (opts->cpuset_clone_children)
+ root->flags = ctx->flags;
+ if (ctx->release_agent)
+ strcpy(root->release_agent_path, ctx->release_agent);
+ if (ctx->name)
+ strcpy(root->name, ctx->name);
+ if (ctx->cpuset_clone_children)
set_bit(CGRP_CPUSET_CLONE_CHILDREN, &root->cgrp.flags);
}
@@ -1742,56 +1742,49 @@ int cgroup_setup_root(struct cgroup_root *root, u16 ss_mask, int ref_flags)
return ret;
}
-struct dentry *cgroup_do_mount(struct file_system_type *fs_type, int flags,
- struct cgroup_root *root, unsigned long magic,
- struct cgroup_namespace *ns)
+int cgroup_do_get_tree(struct cgroup_fs_context *ctx)
{
- struct dentry *dentry;
- bool new_sb;
+ int ret;
- dentry = kernfs_mount(fs_type, flags, root->kf_root, magic, &new_sb);
+ ctx->kfc.root = ctx->root->kf_root;
+
+ ret = kernfs_get_tree(&ctx->kfc);
+ if (ret < 0)
+ goto out_cgrp;
/*
* In non-init cgroup namespace, instead of root cgroup's dentry,
* we return the dentry corresponding to the cgroupns->root_cgrp.
*/
- if (!IS_ERR(dentry) && ns != &init_cgroup_ns) {
+ if (ctx->ns != &init_cgroup_ns) {
struct dentry *nsdentry;
struct cgroup *cgrp;
mutex_lock(&cgroup_mutex);
spin_lock_irq(&css_set_lock);
- cgrp = cset_cgroup_from_root(ns->root_cset, root);
+ cgrp = cset_cgroup_from_root(ctx->ns->root_cset, ctx->root);
spin_unlock_irq(&css_set_lock);
mutex_unlock(&cgroup_mutex);
- nsdentry = kernfs_node_dentry(cgrp->kn, dentry->d_sb);
- dput(dentry);
- dentry = nsdentry;
+ nsdentry = kernfs_node_dentry(cgrp->kn, ctx->kfc.fc.root->d_sb);
+ dput(ctx->kfc.fc.root);
+ ctx->kfc.fc.root = nsdentry;
}
- if (IS_ERR(dentry) || !new_sb)
- cgroup_put(&root->cgrp);
+ ret = 0;
+ if (ctx->kfc.new_sb_created)
+ goto out_cgrp;
+ return 0;
- return dentry;
+out_cgrp:
+ return ret;
}
-static struct dentry *cgroup_mount(struct file_system_type *fs_type,
- int flags, const char *unused_dev_name,
- void *data)
+static int cgroup_get_tree(struct fs_context *fc)
{
- struct cgroup_namespace *ns = current->nsproxy->cgroup_ns;
- struct dentry *dentry;
-
- get_cgroup_ns(ns);
-
- /* Check if the caller has permission to mount. */
- if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN)) {
- put_cgroup_ns(ns);
- return ERR_PTR(-EPERM);
- }
+ struct cgroup_fs_context *ctx = container_of(fc, struct cgroup_fs_context, kfc.fc);
/*
* The first time anyone tries to mount a cgroup, enable the list
@@ -1800,24 +1793,80 @@ static struct dentry *cgroup_mount(struct file_system_type *fs_type,
if (!use_task_css_set_links)
cgroup_enable_task_cg_lists();
- if (fs_type == &cgroup2_fs_type) {
- if (data) {
- pr_err("cgroup2: unknown option \"%s\"\n", (char *)data);
- put_cgroup_ns(ns);
- return ERR_PTR(-EINVAL);
- }
+ switch (ctx->version) {
+ case 1:
+ return cgroup1_get_tree(ctx);
+
+ case 2:
cgrp_dfl_visible = true;
cgroup_get_live(&cgrp_dfl_root.cgrp);
- dentry = cgroup_do_mount(&cgroup2_fs_type, flags, &cgrp_dfl_root,
- CGROUP2_SUPER_MAGIC, ns);
- } else {
- dentry = cgroup1_mount(&cgroup_fs_type, flags, data,
- CGROUP_SUPER_MAGIC, ns);
+ ctx->root = &cgrp_dfl_root;
+ return cgroup_do_get_tree(ctx);
+
+ default:
+ BUG();
}
+}
+
+static int cgroup_parse_option(struct fs_context *fc, char *p)
+{
+ struct cgroup_fs_context *ctx = container_of(fc, struct cgroup_fs_context, kfc.fc);
+
+ if (ctx->version == 1)
+ return cgroup1_parse_option(ctx, p);
+
+ return invalf("cgroup2: Options not supported");
+}
- put_cgroup_ns(ns);
- return dentry;
+static int cgroup_validate(struct fs_context *fc)
+{
+ struct cgroup_fs_context *ctx = container_of(fc, struct cgroup_fs_context, kfc.fc);
+
+ if (ctx->version)
+ return cgroup1_validate(ctx);
+ return 0;
+}
+
+/*
+ * Destroy a cgroup filesystem context.
+ */
+static void cgroup_fs_context_free(struct fs_context *fc)
+{
+ struct cgroup_fs_context *ctx = container_of(fc, struct cgroup_fs_context, kfc.fc);
+
+ kfree(ctx->name);
+ kfree(ctx->release_agent);
+ cgroup_put(&ctx->root->cgrp);
+ put_cgroup_ns(ctx->ns);
+ kernfs_free_fs_context(&ctx->kfc);
+}
+
+static const struct fs_context_operations cgroup_fs_context_ops = {
+ .free = cgroup_fs_context_free,
+ .parse_option = cgroup_parse_option,
+ .validate = cgroup_validate,
+ .get_tree = cgroup_get_tree,
+};
+
+/*
+ * Initialise the cgroup filesystem creation/reconfiguration context. Notably,
+ * we select the namespace we're going to use.
+ */
+static int cgroup_init_fs_context(struct fs_context *fc, struct super_block *src_sb)
+{
+ struct cgroup_fs_context *ctx = container_of(fc, struct cgroup_fs_context, kfc.fc);
+ struct cgroup_namespace *ns = current->nsproxy->cgroup_ns;
+
+ /* Check if the caller has permission to mount. */
+ if (!ns_capable(ns->user_ns, CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ctx->ns = get_cgroup_ns(ns);
+ ctx->version = (fc->fs_type == &cgroup2_fs_type) ? 2 : 1;
+ ctx->kfc.magic = (ctx->version == 2) ? CGROUP2_SUPER_MAGIC : CGROUP_SUPER_MAGIC;
+ ctx->kfc.fc.ops = &cgroup_fs_context_ops;
+ return 0;
}
static void cgroup_kill_sb(struct super_block *sb)
@@ -1842,17 +1891,19 @@ static void cgroup_kill_sb(struct super_block *sb)
}
struct file_system_type cgroup_fs_type = {
- .name = "cgroup",
- .mount = cgroup_mount,
- .kill_sb = cgroup_kill_sb,
- .fs_flags = FS_USERNS_MOUNT,
+ .name = "cgroup",
+ .fs_context_size = sizeof(struct cgroup_fs_context),
+ .init_fs_context = cgroup_init_fs_context,
+ .kill_sb = cgroup_kill_sb,
+ .fs_flags = FS_USERNS_MOUNT,
};
static struct file_system_type cgroup2_fs_type = {
- .name = "cgroup2",
- .mount = cgroup_mount,
- .kill_sb = cgroup_kill_sb,
- .fs_flags = FS_USERNS_MOUNT,
+ .name = "cgroup2",
+ .fs_context_size = sizeof(struct cgroup_fs_context),
+ .init_fs_context = cgroup_init_fs_context,
+ .kill_sb = cgroup_kill_sb,
+ .fs_flags = FS_USERNS_MOUNT,
};
int cgroup_path_ns_locked(struct cgroup *cgrp, char *buf, size_t buflen,
@@ -4460,11 +4511,12 @@ static void __init cgroup_init_subsys(struct cgroup_subsys *ss, bool early)
*/
int __init cgroup_init_early(void)
{
- static struct cgroup_sb_opts __initdata opts;
+ static struct cgroup_fs_context __initdata ctx;
struct cgroup_subsys *ss;
int i;
- init_cgroup_root(&cgrp_dfl_root, &opts);
+ ctx.root = &cgrp_dfl_root;
+ init_cgroup_root(&ctx);
cgrp_dfl_root.cgrp.self.flags |= CSS_NO_REF;
RCU_INIT_POINTER(init_task.cgroups, &init_css_set);
[toc] | [prev] | [next] | [standalone]
| From | Tejun Heo <tj@kernel.org> |
|---|---|
| Date | 2017-06-14 20:00 +0200 |
| Subject | Re: [PATCH 27/27] kernfs, sysfs, cgroup: Support fs_context [ver #5] |
| Message-ID | <tSkKd-8fL-7@gated-at.bofh.it> |
| In reply to | #1665953 |
Hello, David. On Wed, Jun 14, 2017 at 04:19:19PM +0100, David Howells wrote: > Make kernfs support superblock creation/mount/remount with fs_context. > > This requires that sysfs and cgroup, which are built on kernfs, be made to > support fs_context also. Can you please include a brief rationale for doing this and include a pointer to the fuller description on what's going on? > Weirdies: > > (*) cgroup_do_get_tree() calls cset_cgroup_from_root() with locks held, > but then uses the resulting pointer after dropping the locks. I'm > told this is okay and needs commenting. Yeah, will add the comment. > (*) The cgroup refcount web. This really needs documenting. If you're talking about the mount refcnt part, yeah, it's confusing to me too and we definitely need to document it better. > (*) cgroup2 only has one root? Yeap. Thanks. -- tejun
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-15 00:40 +0200 |
| Subject | Re: [PATCH 27/27] ... and the intel_rdt driver |
| Message-ID | <tSp7b-2DF-9@gated-at.bofh.it> |
| In reply to | #1665953 |
This also needs the attached addition to fix the intel_rdt driver.
David
---
diff --git a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
index f5af0cc7eb0d..d026701894fd 100644
--- a/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
+++ b/arch/x86/kernel/cpu/intel_rdt_rdtgroup.c
@@ -35,6 +35,11 @@
#include <asm/intel_rdt.h>
#include <asm/intel_rdt_common.h>
+struct rdt_fs_context {
+ struct kernfs_fs_context kfc;
+ bool enable_cdp;
+};
+
DEFINE_STATIC_KEY_FALSE(rdt_enable_key);
struct kernfs_root *rdt_root;
struct rdtgroup rdtgroup_default;
@@ -743,22 +748,6 @@ static void cdp_disable(void)
}
}
-static int parse_rdtgroupfs_options(char *data)
-{
- char *token, *o = data;
- int ret = 0;
-
- while ((token = strsep(&o, ",")) != NULL) {
- if (!*token)
- return -EINVAL;
-
- if (!strcmp(token, "cdp"))
- ret = cdp_enable();
- }
-
- return ret;
-}
-
/*
* We don't allow rdtgroup directories to be created anywhere
* except the root directory. Thus when looking for the rdtgroup
@@ -823,11 +812,9 @@ void rdtgroup_kn_unlock(struct kernfs_node *kn)
}
}
-static struct dentry *rdt_mount(struct file_system_type *fs_type,
- int flags, const char *unused_dev_name,
- void *data)
+static int rdt_get_tree(struct fs_context *fc)
{
- struct dentry *dentry;
+ struct rdt_fs_context *ctx = container_of(fc, struct rdt_fs_context, kfc.fc);
int ret;
mutex_lock(&rdtgroup_mutex);
@@ -835,27 +822,25 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type,
* resctrl file system can only be mounted once.
*/
if (static_branch_unlikely(&rdt_enable_key)) {
- dentry = ERR_PTR(-EBUSY);
+ errorf("intel_rdt: Can only mount once");
+ ret = -EBUSY;
goto out;
}
- ret = parse_rdtgroupfs_options(data);
- if (ret) {
- dentry = ERR_PTR(ret);
- goto out_cdp;
+ if (ctx->enable_cdp) {
+ ret = cdp_enable();
+ if (ret < 0)
+ goto out_cdp;
}
closid_init();
ret = rdtgroup_create_info_dir(rdtgroup_default.kn);
- if (ret) {
- dentry = ERR_PTR(ret);
+ if (ret < 0)
goto out_cdp;
- }
- dentry = kernfs_mount(fs_type, flags, rdt_root,
- RDTGROUP_SUPER_MAGIC, NULL);
- if (IS_ERR(dentry))
+ ret = kernfs_get_tree(&ctx->kfc);
+ if (ret < 0)
goto out_cdp;
static_branch_enable(&rdt_enable_key);
@@ -865,8 +850,42 @@ static struct dentry *rdt_mount(struct file_system_type *fs_type,
cdp_disable();
out:
mutex_unlock(&rdtgroup_mutex);
+ return ret;
+}
+
+static int rdt_parse_option(struct fs_context *fc, char *p)
+{
+ struct rdt_fs_context *ctx = container_of(fc, struct rdt_fs_context, kfc.fc);
- return dentry;
+ if (strcmp(p, "cdp") == 0) {
+ ctx->enable_cdp = true;
+ return 0;
+ }
+
+ return invalf("intel_rdt: Unknown option");
+}
+
+static void rdt_fs_context_free(struct fs_context *fc)
+{
+ struct rdt_fs_context *ctx = container_of(fc, struct rdt_fs_context, kfc.fc);
+
+ kernfs_free_fs_context(&ctx->kfc);
+}
+
+static const struct fs_context_operations rdt_fs_context_ops = {
+ .free = rdt_fs_context_free,
+ .parse_option = rdt_parse_option,
+ .get_tree = rdt_get_tree,
+};
+
+static int rdt_init_fs_context(struct fs_context *fc, struct super_block *src_sb)
+{
+ struct rdt_fs_context *ctx = container_of(fc, struct rdt_fs_context, kfc.fc);
+
+ ctx->kfc.root = rdt_root;
+ ctx->kfc.magic = RDTGROUP_SUPER_MAGIC;
+ ctx->kfc.fc.ops = &rdt_fs_context_ops;
+ return 0;
}
static int reset_all_ctrls(struct rdt_resource *r)
@@ -994,9 +1013,10 @@ static void rdt_kill_sb(struct super_block *sb)
}
static struct file_system_type rdt_fs_type = {
- .name = "resctrl",
- .mount = rdt_mount,
- .kill_sb = rdt_kill_sb,
+ .name = "resctrl",
+ .fs_context_size = sizeof(struct rdt_fs_context),
+ .init_fs_context = rdt_init_fs_context,
+ .kill_sb = rdt_kill_sb,
};
static int rdtgroup_mkdir(struct kernfs_node *parent_kn, const char *name,
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 26/27] cpuset: Use fs_context [ver #5] |
| Message-ID | <tSifo-6QJ-27@gated-at.bofh.it> |
| In reply to | #1665947 |
Make the cpuset filesystem use the filesystem context. This is potentially
tricky as the cpuset fs is almost an alias for the cgroup filesystem, but
with some special parameters.
This can, however, be handled by setting up an appropriate cgroup
filesystem and returning the root directory of that as the root dir of this
one.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Tejun Heo <tj@kernel.org>
---
kernel/cgroup/cpuset.c | 58 +++++++++++++++++++++++++++++++++++++-----------
1 file changed, 45 insertions(+), 13 deletions(-)
diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c
index ae643412948a..c25914a4e41a 100644
--- a/kernel/cgroup/cpuset.c
+++ b/kernel/cgroup/cpuset.c
@@ -38,7 +38,7 @@
#include <linux/mm.h>
#include <linux/memory.h>
#include <linux/export.h>
-#include <linux/mount.h>
+#include <linux/fs_context.h>
#include <linux/namei.h>
#include <linux/pagemap.h>
#include <linux/proc_fs.h>
@@ -303,25 +303,57 @@ static DECLARE_WAIT_QUEUE_HEAD(cpuset_attach_wq);
* users. If someone tries to mount the "cpuset" filesystem, we
* silently switch it to mount "cgroup" instead
*/
-static struct dentry *cpuset_mount(struct file_system_type *fs_type,
- int flags, const char *unused_dev_name, void *data)
+static int cpuset_get_tree(struct fs_context *fc)
{
- struct file_system_type *cgroup_fs = get_fs_type("cgroup");
- struct dentry *ret = ERR_PTR(-ENODEV);
+ struct file_system_type *cgroup_fs;
+ struct fs_context *cg_fc;
+ int ret = -ENODEV;
+
+ cgroup_fs = get_fs_type("cgroup");
if (cgroup_fs) {
- char mountopts[] =
- "cpuset,noprefix,"
- "release_agent=/sbin/cpuset_release_agent";
- ret = cgroup_fs->mount(cgroup_fs, flags,
- unused_dev_name, mountopts);
- put_filesystem(cgroup_fs);
+ ret = PTR_ERR(cgroup_fs);
+ goto out;
+ }
+
+ cg_fc = vfs_new_fs_context(cgroup_fs, NULL, 0, FS_CONTEXT_FOR_NEW);
+ put_filesystem(cgroup_fs);
+ if (IS_ERR(cg_fc)) {
+ ret = PTR_ERR(cg_fc);
+ goto out;
}
+
+ ret = generic_monolithic_mount_data(
+ fc, "cpuset,noprefix,release_agent=/sbin/cpuset_release_agent");
+ if (ret < 0)
+ goto out_fc;
+
+ ret = vfs_get_tree(cg_fc);
+ if (ret < 0)
+ goto out_fc;
+
+ fc->root = dget(cg_fc->root);
+ ret = 0;
+
+out_fc:
+ put_fs_context(cg_fc);
+out:
return ret;
}
+static const struct fs_context_operations cpuset_fs_context_ops = {
+ .get_tree = cpuset_get_tree,
+};
+
+static int cpuset_init_fs_context(struct fs_context *fc, struct super_block *src_sb)
+{
+ fc->ops = &cpuset_fs_context_ops;
+ return 0;
+}
+
static struct file_system_type cpuset_fs_type = {
- .name = "cpuset",
- .mount = cpuset_mount,
+ .name = "cpuset",
+ .fs_context_size = sizeof(struct fs_context),
+ .init_fs_context = cpuset_init_fs_context,
};
/*
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 16/27] proc: Add fs_context support to procfs [ver #5] |
| Message-ID | <tSifo-6QJ-35@gated-at.bofh.it> |
| In reply to | #1665947 |
Add fs_context support to procfs.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/proc/inode.c | 2 -
fs/proc/internal.h | 2 -
fs/proc/root.c | 175 ++++++++++++++++++++++++++++++++++------------------
3 files changed, 116 insertions(+), 63 deletions(-)
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index a4bf66af0ba9..a642bee67a53 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -118,7 +118,7 @@ const struct super_operations proc_sops = {
.drop_inode = generic_delete_inode,
.evict_inode = proc_evict_inode,
.statfs = simple_statfs,
- .remount_fs = proc_remount,
+ .remount_fs_fc = proc_remount,
.show_options = proc_show_options,
};
diff --git a/fs/proc/internal.h b/fs/proc/internal.h
index b681533f59dd..78d1e4ff5f76 100644
--- a/fs/proc/internal.h
+++ b/fs/proc/internal.h
@@ -262,7 +262,7 @@ static inline void proc_tty_init(void) {}
extern struct proc_dir_entry proc_root;
extern void proc_self_init(void);
-extern int proc_remount(struct super_block *, int *, char *);
+extern int proc_remount(struct super_block *, struct fs_context *);
/*
* task_[no]mmu.c
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 3dd3838d9e08..22d8e8f20c38 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -18,14 +18,23 @@
#include <linux/module.h>
#include <linux/bitops.h>
#include <linux/user_namespace.h>
-#include <linux/mount.h>
+#include <linux/fs_context.h>
#include <linux/pid_namespace.h>
#include <linux/parser.h>
#include <linux/cred.h>
#include <linux/magic.h>
+#include <linux/slab.h>
#include "internal.h"
+struct proc_fs_context {
+ struct fs_context fc;
+ struct pid_namespace *pid_ns;
+ unsigned long mask;
+ int hidepid;
+ int gid;
+};
+
enum {
Opt_gid, Opt_hidepid, Opt_err,
};
@@ -36,56 +45,60 @@ static const match_table_t tokens = {
{Opt_err, NULL},
};
-static int proc_parse_options(char *options, struct pid_namespace *pid)
+static int proc_parse_mount_option(struct fs_context *fc, char *p)
{
- char *p;
+ struct proc_fs_context *ctx = container_of(fc, struct proc_fs_context, fc);
substring_t args[MAX_OPT_ARGS];
- int option;
-
- if (!options)
- return 1;
-
- while ((p = strsep(&options, ",")) != NULL) {
- int token;
- if (!*p)
- continue;
-
- args[0].to = args[0].from = NULL;
- token = match_token(p, tokens, args);
- switch (token) {
- case Opt_gid:
- if (match_int(&args[0], &option))
- return 0;
- pid->pid_gid = make_kgid(current_user_ns(), option);
- break;
- case Opt_hidepid:
- if (match_int(&args[0], &option))
- return 0;
- if (option < HIDEPID_OFF ||
- option > HIDEPID_INVISIBLE) {
- pr_err("proc: hidepid value must be between 0 and 2.\n");
- return 0;
- }
- pid->hide_pid = option;
- break;
- default:
- pr_err("proc: unrecognized mount option \"%s\" "
- "or missing value\n", p);
- return 0;
+ int token;
+
+ args[0].to = args[0].from = NULL;
+ token = match_token(p, tokens, args);
+ switch (token) {
+ case Opt_gid:
+ if (match_int(&args[0], &ctx->gid))
+ return invalf("procfs: Unparseable gid= argument");
+ break;
+
+ case Opt_hidepid:
+ if (match_int(&args[0], &ctx->hidepid))
+ return invalf("procfs: Unparseable hidepid= argument");
+ if (ctx->hidepid < HIDEPID_OFF ||
+ ctx->hidepid > HIDEPID_INVISIBLE) {
+ pr_err("proc: hidepid value must be between 0 and 2.\n");
+ return invalf("procfs: Invalid hidepid= argument");
}
+ break;
+
+ default:
+ pr_err("proc: unrecognized mount option \"%s\" "
+ "or missing value\n", p);
+ return invalf("procfs: Invalid mount option or missing value");
}
- return 1;
+ ctx->mask |= 1 << token;
+ return 0;
+}
+
+static void proc_set_options(struct super_block *s,
+ struct fs_context *fc,
+ struct pid_namespace *pid_ns,
+ struct user_namespace *user_ns)
+{
+ struct proc_fs_context *ctx = container_of(fc, struct proc_fs_context, fc);
+
+ if (ctx->mask & (1 << Opt_gid))
+ pid_ns->pid_gid = make_kgid(user_ns, ctx->gid);
+ if (ctx->mask & (1 << Opt_hidepid))
+ pid_ns->hide_pid = ctx->hidepid;
}
-static int proc_fill_super(struct super_block *s, void *data, int silent)
+static int proc_fill_super(struct super_block *s, struct fs_context *fc)
{
- struct pid_namespace *ns = get_pid_ns(s->s_fs_info);
+ struct pid_namespace *pid_ns = get_pid_ns(s->s_fs_info);
struct inode *root_inode;
int ret;
- if (!proc_parse_options(data, ns))
- return -EINVAL;
+ proc_set_options(s, fc, pid_ns, current_user_ns());
/* User space would break if executables or devices appear on proc */
s->s_iflags |= SB_I_USERNS_VISIBLE | SB_I_NOEXEC | SB_I_NODEV;
@@ -102,7 +115,7 @@ static int proc_fill_super(struct super_block *s, void *data, int silent)
* top of it
*/
s->s_stack_depth = FILESYSTEM_MAX_STACK_DEPTH;
-
+
pde_get(&proc_root);
root_inode = proc_get_inode(s, &proc_root);
if (!root_inode) {
@@ -123,27 +136,45 @@ static int proc_fill_super(struct super_block *s, void *data, int silent)
return proc_setup_thread_self(s);
}
-int proc_remount(struct super_block *sb, int *flags, char *data)
+int proc_remount(struct super_block *sb, struct fs_context *fc)
{
struct pid_namespace *pid = sb->s_fs_info;
sync_filesystem(sb);
- return !proc_parse_options(data, pid);
+
+ if (fc)
+ proc_set_options(sb, fc, pid, current_user_ns());
+ return 0;
}
-static struct dentry *proc_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name, void *data)
+static int proc_get_tree(struct fs_context *fc)
{
- struct pid_namespace *ns;
+ struct proc_fs_context *ctx = container_of(fc, struct proc_fs_context, fc);
- if (flags & SB_KERNMOUNT) {
- ns = data;
- data = NULL;
- } else {
- ns = task_active_pid_ns(current);
- }
+ return mount_ns_fc(fc, proc_fill_super, ctx->pid_ns);
+}
+
+static void proc_fs_context_free(struct fs_context *fc)
+{
+ struct proc_fs_context *ctx = container_of(fc, struct proc_fs_context, fc);
- return mount_ns(fs_type, flags, data, ns, ns->user_ns, proc_fill_super);
+ if (ctx->pid_ns)
+ put_pid_ns(ctx->pid_ns);
+}
+
+static const struct fs_context_operations proc_fs_context_ops = {
+ .free = proc_fs_context_free,
+ .parse_option = proc_parse_mount_option,
+ .get_tree = proc_get_tree,
+};
+
+static int proc_init_fs_context(struct fs_context *fc, struct super_block *src_sb)
+{
+ struct proc_fs_context *ctx = container_of(fc, struct proc_fs_context, fc);
+
+ ctx->pid_ns = get_pid_ns(task_active_pid_ns(current));
+ ctx->fc.ops = &proc_fs_context_ops;
+ return 0;
}
static void proc_kill_sb(struct super_block *sb)
@@ -161,7 +192,8 @@ static void proc_kill_sb(struct super_block *sb)
static struct file_system_type proc_fs_type = {
.name = "proc",
- .mount = proc_mount,
+ .fs_context_size = sizeof(struct proc_fs_context),
+ .init_fs_context = proc_init_fs_context,
.kill_sb = proc_kill_sb,
.fs_flags = FS_USERNS_MOUNT,
};
@@ -209,7 +241,7 @@ static struct dentry *proc_root_lookup(struct inode * dir, struct dentry * dentr
{
if (!proc_pid_lookup(dir, dentry, flags))
return NULL;
-
+
return proc_lookup(dir, dentry, flags);
}
@@ -248,12 +280,12 @@ static const struct inode_operations proc_root_inode_operations = {
* This is the root "inode" in the /proc tree..
*/
struct proc_dir_entry proc_root = {
- .low_ino = PROC_ROOT_INO,
- .namelen = 5,
- .mode = S_IFDIR | S_IRUGO | S_IXUGO,
- .nlink = 2,
+ .low_ino = PROC_ROOT_INO,
+ .namelen = 5,
+ .mode = S_IFDIR | S_IRUGO | S_IXUGO,
+ .nlink = 2,
.count = ATOMIC_INIT(1),
- .proc_iops = &proc_root_inode_operations,
+ .proc_iops = &proc_root_inode_operations,
.proc_fops = &proc_root_operations,
.parent = &proc_root,
.subdir = RB_ROOT,
@@ -262,9 +294,30 @@ struct proc_dir_entry proc_root = {
int pid_ns_prepare_proc(struct pid_namespace *ns)
{
+ struct proc_fs_context *ctx;
+ struct fs_context *fc;
struct vfsmount *mnt;
+ int ret;
+
+ fc = vfs_new_fs_context(&proc_fs_type, NULL, 0, FS_CONTEXT_FOR_NEW);
+ if (IS_ERR(fc))
+ return PTR_ERR(fc);
+
+ ctx = container_of(fc, struct proc_fs_context, fc);
+ if (ctx->pid_ns != ns) {
+ put_pid_ns(ctx->pid_ns);
+ get_pid_ns(ns);
+ ctx->pid_ns = ns;
+ }
+
+ ret = vfs_get_tree(fc);
+ if (ret < 0) {
+ put_fs_context(fc);
+ return ret;
+ }
- mnt = kern_mount_data(&proc_fs_type, ns);
+ mnt = kern_mount_data_fc(fc);
+ put_fs_context(fc);
if (IS_ERR(mnt))
return PTR_ERR(mnt);
[toc] | [prev] | [next] | [standalone]
| From | Al Viro <viro@ZenIV.linux.org.uk> |
|---|---|
| Date | 2017-06-15 12:20 +0200 |
| Subject | Re: [PATCH 16/27] proc: Add fs_context support to procfs [ver #5] |
| Message-ID | <tSA2B-1bK-1@gated-at.bofh.it> |
| In reply to | #1665955 |
On Wed, Jun 14, 2017 at 04:17:43PM +0100, David Howells wrote:
> int pid_ns_prepare_proc(struct pid_namespace *ns)
> {
> + struct proc_fs_context *ctx;
> + struct fs_context *fc;
> struct vfsmount *mnt;
> + int ret;
> +
> + fc = vfs_new_fs_context(&proc_fs_type, NULL, 0, FS_CONTEXT_FOR_NEW);
> + if (IS_ERR(fc))
> + return PTR_ERR(fc);
> +
> + ctx = container_of(fc, struct proc_fs_context, fc);
> + if (ctx->pid_ns != ns) {
> + put_pid_ns(ctx->pid_ns);
> + get_pid_ns(ns);
> + ctx->pid_ns = ns;
> + }
> +
> + ret = vfs_get_tree(fc);
> + if (ret < 0) {
> + put_fs_context(fc);
> + return ret;
> + }
>
> - mnt = kern_mount_data(&proc_fs_type, ns);
> + mnt = kern_mount_data_fc(fc);
> + put_fs_context(fc);
Same as with ipc; do you need to go through dynamic allocation,
container_of, patching it up, etc.?
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 01/27] Provide a function to create a NUL-terminated string from unterminated data [ver #5] |
| Message-ID | <tSifo-6QJ-33@gated-at.bofh.it> |
| In reply to | #1665947 |
Provide a function, kmemdup_nul(), that will create a NUL-terminated string
from an unterminated character array where the length is known in advance.
This is better than kstrndup() in situations where we already know the
string length as the strnlen() in kstrndup() is superfluous.
Signed-off-by: David Howells <dhowells@redhat.com>
---
include/linux/string.h | 1 +
mm/util.c | 24 ++++++++++++++++++++++++
2 files changed, 25 insertions(+)
diff --git a/include/linux/string.h b/include/linux/string.h
index 537918f8a98e..3dd944cfe171 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -131,6 +131,7 @@ extern char *kstrdup(const char *s, gfp_t gfp) __malloc;
extern const char *kstrdup_const(const char *s, gfp_t gfp);
extern char *kstrndup(const char *s, size_t len, gfp_t gfp);
extern void *kmemdup(const void *src, size_t len, gfp_t gfp);
+extern char *kmemdup_nul(const char *s, size_t len, gfp_t gfp);
extern char **argv_split(gfp_t gfp, const char *str, int *argcp);
extern void argv_free(char **argv);
diff --git a/mm/util.c b/mm/util.c
index 26be6407abd7..21ddf90f883d 100644
--- a/mm/util.c
+++ b/mm/util.c
@@ -83,6 +83,8 @@ EXPORT_SYMBOL(kstrdup_const);
* @s: the string to duplicate
* @max: read at most @max chars from @s
* @gfp: the GFP mask used in the kmalloc() call when allocating memory
+ *
+ * Note: Use kmemdup_nul() instead if the size is known exactly.
*/
char *kstrndup(const char *s, size_t max, gfp_t gfp)
{
@@ -121,6 +123,28 @@ void *kmemdup(const void *src, size_t len, gfp_t gfp)
EXPORT_SYMBOL(kmemdup);
/**
+ * kmemdup_nul - Create a NUL-terminated string from unterminated data
+ * @s: The data to stringify
+ * @len: The size of the data
+ * @gfp: the GFP mask used in the kmalloc() call when allocating memory
+ */
+char *kmemdup_nul(const char *s, size_t len, gfp_t gfp)
+{
+ char *buf;
+
+ if (!s)
+ return NULL;
+
+ buf = kmalloc_track_caller(len + 1, gfp);
+ if (buf) {
+ memcpy(buf, s, len);
+ buf[len] = '\0';
+ }
+ return buf;
+}
+EXPORT_SYMBOL(kmemdup_nul);
+
+/**
* memdup_user - duplicate memory region from user space
*
* @src: source address in user space
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 09/27] VFS: Add LSM hooks for filesystem context [ver #5] |
| Message-ID | <tSifo-6QJ-39@gated-at.bofh.it> |
| In reply to | #1665947 |
Add LSM hooks for use by the filesystem context code. This includes:
(1) Hooks to handle allocation, duplication and freeing of the security
record attached to a filesystem context.
(2) A hook to snoop a mount options in key[=val] form. If the LSM decides
it wants to handle it, it can suppress the option being passed to the
filesystem. Note that 'val' may include commas and binary data with
the fsopen patch.
(3) A hook to transfer the security from the context to a newly created
superblock.
(4) A hook to rule on whether a path point can be used as a mountpoint.
These are intended to replace:
security_sb_copy_data
security_sb_kern_mount
security_sb_mount
security_sb_set_mnt_opts
security_sb_clone_mnt_opts
security_sb_parse_opts_str
Signed-off-by: David Howells <dhowells@redhat.com>
cc: linux-security-module@vger.kernel.org
---
include/linux/lsm_hooks.h | 45 +++++++++++
include/linux/security.h | 33 ++++++++
security/security.c | 30 +++++++
security/selinux/hooks.c | 181 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 289 insertions(+)
diff --git a/include/linux/lsm_hooks.h b/include/linux/lsm_hooks.h
index 080f34e66017..62500658cc9f 100644
--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h
@@ -75,6 +75,38 @@
* should enable secure mode.
* @bprm contains the linux_binprm structure.
*
+ * Security hooks for mount using fd context.
+ *
+ * @fs_context_alloc:
+ * Allocate and attach a security structure to sc->security. This pointer
+ * is initialised to NULL by the caller.
+ * @fc indicates the new filesystem context.
+ * @src_sb indicates the source superblock of a submount.
+ * @fs_context_dup:
+ * Allocate and attach a security structure to sc->security. This pointer
+ * is initialised to NULL by the caller.
+ * @fc indicates the new filesystem context.
+ * @src_fc indicates the original filesystem context.
+ * @fs_context_free:
+ * Clean up a filesystem context.
+ * @fc indicates the filesystem context.
+ * @fs_context_parse_option:
+ * Userspace provided an option to configure a superblock. The LSM may
+ * reject it with an error and may use it for itself, in which case it
+ * should return 1; otherwise it should return 0 to pass it on to the
+ * filesystem.
+ * @fc indicates the filesystem context.
+ * @p indicates the option in "key[=val]" form.
+ * @sb_get_tree:
+ * Assign the security to a newly created superblock.
+ * @fc indicates the filesystem context.
+ * @fc->root indicates the root that will be mounted.
+ * @fc->root->d_sb points to the superblock.
+ * @sb_mountpoint:
+ * Equivalent of sb_mount, but with an fs_context.
+ * @fc indicates the filesystem context.
+ * @mountpoint indicates the path on which the mount will take place.
+ *
* Security hooks for filesystem operations.
*
* @sb_alloc_security:
@@ -1372,6 +1404,13 @@ union security_list_options {
void (*bprm_committing_creds)(struct linux_binprm *bprm);
void (*bprm_committed_creds)(struct linux_binprm *bprm);
+ int (*fs_context_alloc)(struct fs_context *fc, struct super_block *src_sb);
+ int (*fs_context_dup)(struct fs_context *fc, struct fs_context *src_sc);
+ void (*fs_context_free)(struct fs_context *fc);
+ int (*fs_context_parse_option)(struct fs_context *fc, char *opt);
+ int (*sb_get_tree)(struct fs_context *fc);
+ int (*sb_mountpoint)(struct fs_context *fc, struct path *mountpoint);
+
int (*sb_alloc_security)(struct super_block *sb);
void (*sb_free_security)(struct super_block *sb);
int (*sb_copy_data)(char *orig, char *copy);
@@ -1683,6 +1722,12 @@ struct security_hook_heads {
struct list_head bprm_secureexec;
struct list_head bprm_committing_creds;
struct list_head bprm_committed_creds;
+ struct list_head fs_context_alloc;
+ struct list_head fs_context_dup;
+ struct list_head fs_context_free;
+ struct list_head fs_context_parse_option;
+ struct list_head sb_get_tree;
+ struct list_head sb_mountpoint;
struct list_head sb_alloc_security;
struct list_head sb_free_security;
struct list_head sb_copy_data;
diff --git a/include/linux/security.h b/include/linux/security.h
index af675b576645..e7c774fdffd9 100644
--- a/include/linux/security.h
+++ b/include/linux/security.h
@@ -55,6 +55,7 @@ struct msg_queue;
struct xattr;
struct xfrm_sec_ctx;
struct mm_struct;
+struct fs_context;
/* If capable should audit the security request */
#define SECURITY_CAP_NOAUDIT 0
@@ -224,6 +225,12 @@ int security_bprm_check(struct linux_binprm *bprm);
void security_bprm_committing_creds(struct linux_binprm *bprm);
void security_bprm_committed_creds(struct linux_binprm *bprm);
int security_bprm_secureexec(struct linux_binprm *bprm);
+int security_fs_context_alloc(struct fs_context *fc, struct super_block *sb);
+int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc);
+void security_fs_context_free(struct fs_context *fc);
+int security_fs_context_parse_option(struct fs_context *fc, char *opt);
+int security_sb_get_tree(struct fs_context *fc);
+int security_sb_mountpoint(struct fs_context *fc, struct path *mountpoint);
int security_sb_alloc(struct super_block *sb);
void security_sb_free(struct super_block *sb);
int security_sb_copy_data(char *orig, char *copy);
@@ -520,6 +527,32 @@ static inline int security_bprm_secureexec(struct linux_binprm *bprm)
return cap_bprm_secureexec(bprm);
}
+static inline int security_fs_context_alloc(struct fs_context *fc,
+ struct super_block *src_sb)
+{
+ return 0;
+}
+static inline int security_fs_context_dup(struct fs_context *fc,
+ struct fs_context *src_fc)
+{
+ return 0;
+}
+static inline void security_fs_context_free(struct fs_context *fc)
+{
+}
+static inline int security_fs_context_parse_option(struct fs_context *fc, char *opt)
+{
+ return 0;
+}
+static inline int security_sb_get_tree(struct fs_context *fc)
+{
+ return 0;
+}
+static inline int security_sb_mountpoint(struct fs_context *fc, struct path *mountpoint)
+{
+ return 0;
+}
+
static inline int security_sb_alloc(struct super_block *sb)
{
return 0;
diff --git a/security/security.c b/security/security.c
index b9fea3999cf8..27b195966cad 100644
--- a/security/security.c
+++ b/security/security.c
@@ -316,6 +316,36 @@ int security_bprm_secureexec(struct linux_binprm *bprm)
return call_int_hook(bprm_secureexec, 0, bprm);
}
+int security_fs_context_alloc(struct fs_context *fc, struct super_block *src_sb)
+{
+ return call_int_hook(fs_context_alloc, 0, fc, src_sb);
+}
+
+int security_fs_context_dup(struct fs_context *fc, struct fs_context *src_fc)
+{
+ return call_int_hook(fs_context_dup, 0, fc, src_fc);
+}
+
+void security_fs_context_free(struct fs_context *fc)
+{
+ call_void_hook(fs_context_free, fc);
+}
+
+int security_fs_context_parse_option(struct fs_context *fc, char *opt)
+{
+ return call_int_hook(fs_context_parse_option, 0, fc, opt);
+}
+
+int security_sb_get_tree(struct fs_context *fc)
+{
+ return call_int_hook(sb_get_tree, 0, fc);
+}
+
+int security_sb_mountpoint(struct fs_context *fc, struct path *mountpoint)
+{
+ return call_int_hook(sb_mountpoint, 0, fc, mountpoint);
+}
+
int security_sb_alloc(struct super_block *sb)
{
return call_int_hook(sb_alloc_security, 0, sb);
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 7e498b16aed3..c93a21119fe3 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -47,6 +47,7 @@
#include <linux/fdtable.h>
#include <linux/namei.h>
#include <linux/mount.h>
+#include <linux/fs_context.h>
#include <linux/netfilter_ipv4.h>
#include <linux/netfilter_ipv6.h>
#include <linux/tty.h>
@@ -2826,6 +2827,179 @@ static int selinux_umount(struct vfsmount *mnt, int flags)
FILESYSTEM__UNMOUNT, NULL);
}
+/* fsopen mount context operations */
+
+static int selinux_fs_context_alloc(struct fs_context *fc,
+ struct super_block *src_sb)
+{
+ struct security_mnt_opts *opts;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return -ENOMEM;
+
+ fc->security = opts;
+ return 0;
+}
+
+static int selinux_fs_context_dup(struct fs_context *fc,
+ struct fs_context *src_fc)
+{
+ const struct security_mnt_opts *src = src_fc->security;
+ struct security_mnt_opts *opts;
+ int i, n;
+
+ opts = kzalloc(sizeof(*opts), GFP_KERNEL);
+ if (!opts)
+ return -ENOMEM;
+ fc->security = opts;
+
+ if (!src || !src->num_mnt_opts)
+ return 0;
+ n = opts->num_mnt_opts = src->num_mnt_opts;
+
+ if (src->mnt_opts) {
+ opts->mnt_opts = kcalloc(n, sizeof(char *), GFP_KERNEL);
+ if (!opts->mnt_opts)
+ return -ENOMEM;
+
+ for (i = 0; i < n; i++) {
+ if (src->mnt_opts[i]) {
+ opts->mnt_opts[i] = kstrdup(src->mnt_opts[i],
+ GFP_KERNEL);
+ if (!opts->mnt_opts[i])
+ return -ENOMEM;
+ }
+ }
+ }
+
+ if (src->mnt_opts_flags) {
+ opts->mnt_opts_flags = kmemdup(src->mnt_opts_flags,
+ n * sizeof(int), GFP_KERNEL);
+ if (!opts->mnt_opts_flags)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void selinux_fs_context_free(struct fs_context *fc)
+{
+ struct security_mnt_opts *opts = fc->security;
+
+ security_free_mnt_opts(opts);
+ fc->security = NULL;
+}
+
+static int selinux_fs_context_parse_option(struct fs_context *fc, char *opt)
+{
+ struct security_mnt_opts *opts = fc->security;
+ substring_t args[MAX_OPT_ARGS];
+ unsigned int have;
+ char *c, **oo;
+ int token, ctx, i, *of;
+
+ token = match_token(opt, tokens, args);
+ if (token == Opt_error)
+ return 0; /* Doesn't belong to us. */
+
+ have = 0;
+ for (i = 0; i < opts->num_mnt_opts; i++)
+ have |= 1 << opts->mnt_opts_flags[i];
+ if (have & (1 << token))
+ return invalf("SELinux: Duplicate mount options");
+
+ switch (token) {
+ case Opt_context:
+ if (have & (1 << Opt_defcontext))
+ goto incompatible;
+ ctx = CONTEXT_MNT;
+ goto copy_context_string;
+
+ case Opt_fscontext:
+ ctx = FSCONTEXT_MNT;
+ goto copy_context_string;
+
+ case Opt_rootcontext:
+ ctx = ROOTCONTEXT_MNT;
+ goto copy_context_string;
+
+ case Opt_defcontext:
+ if (have & (1 << Opt_context))
+ goto incompatible;
+ ctx = DEFCONTEXT_MNT;
+ goto copy_context_string;
+
+ case Opt_labelsupport:
+ return 1;
+
+ default:
+ return invalf("SELinux: Unknown mount option");
+ }
+
+copy_context_string:
+ if (opts->num_mnt_opts > 3)
+ return invalf("SELinux: Too many options");
+
+ of = krealloc(opts->mnt_opts_flags,
+ (opts->num_mnt_opts + 1) * sizeof(int), GFP_KERNEL);
+ if (!of)
+ return -ENOMEM;
+ of[opts->num_mnt_opts] = 0;
+ opts->mnt_opts_flags = of;
+
+ oo = krealloc(opts->mnt_opts,
+ (opts->num_mnt_opts + 1) * sizeof(char *), GFP_KERNEL);
+ if (!oo)
+ return -ENOMEM;
+ oo[opts->num_mnt_opts] = NULL;
+ opts->mnt_opts = oo;
+
+ c = match_strdup(&args[0]);
+ if (!c)
+ return -ENOMEM;
+ opts->mnt_opts[opts->num_mnt_opts] = c;
+ opts->mnt_opts_flags[opts->num_mnt_opts] = ctx;
+ opts->num_mnt_opts++;
+ return 1;
+
+incompatible:
+ return invalf("SELinux: Incompatible mount options");
+}
+
+static int selinux_sb_get_tree(struct fs_context *fc)
+{
+ const struct cred *cred = current_cred();
+ struct common_audit_data ad;
+ int rc;
+
+ rc = selinux_set_mnt_opts(fc->root->d_sb, fc->security, 0, NULL);
+ if (rc)
+ return rc;
+
+ /* Allow all mounts performed by the kernel */
+ if (fc->sb_flags & MS_KERNMOUNT)
+ return 0;
+
+ ad.type = LSM_AUDIT_DATA_DENTRY;
+ ad.u.dentry = fc->root;
+ rc = superblock_has_perm(cred, fc->root->d_sb, FILESYSTEM__MOUNT, &ad);
+ if (rc < 0)
+ errorf("SELinux: Mount of superblock not permitted");
+ return rc;
+}
+
+static int selinux_sb_mountpoint(struct fs_context *fc, struct path *mountpoint)
+{
+ const struct cred *cred = current_cred();
+ int ret;
+
+ ret = path_has_perm(cred, mountpoint, FILE__MOUNTON);
+ if (ret < 0)
+ errorf("SELinux: Mount on mountpoint not permitted");
+ return ret;
+}
+
/* inode security operations */
static int selinux_inode_alloc_security(struct inode *inode)
@@ -6154,6 +6328,13 @@ static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
+ LSM_HOOK_INIT(fs_context_alloc, selinux_fs_context_alloc),
+ LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
+ LSM_HOOK_INIT(fs_context_free, selinux_fs_context_free),
+ LSM_HOOK_INIT(fs_context_parse_option, selinux_fs_context_parse_option),
+ LSM_HOOK_INIT(sb_get_tree, selinux_sb_get_tree),
+ LSM_HOOK_INIT(sb_mountpoint, selinux_sb_mountpoint),
+
LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 25/27] ipc: Convert mqueue fs to fs_context [ver #5] |
| Message-ID | <tSifp-6QJ-41@gated-at.bofh.it> |
| In reply to | #1665947 |
Convert the mqueue filesystem to use the filesystem context stuff.
Notes:
(1) The relevant ipc namespace is selected in when the context is
initialised (and it defaults to the current task's ipc namespace).
The caller can override this before calling vfs_get_tree().
(2) Rather than simply calling kern_mount_data(), mq_init_ns() creates a
context, adjusts it and then does the rest of the mount procedure.
Signed-off-by: David Howells <dhowells@redhat.com>
---
ipc/mqueue.c | 90 ++++++++++++++++++++++++++++++++++++++++++++--------------
1 file changed, 68 insertions(+), 22 deletions(-)
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 9e3a0aab4416..5a0594a79855 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -18,6 +18,7 @@
#include <linux/pagemap.h>
#include <linux/file.h>
#include <linux/mount.h>
+#include <linux/fs_context.h>
#include <linux/namei.h>
#include <linux/sysctl.h>
#include <linux/poll.h>
@@ -42,6 +43,11 @@
#include <net/sock.h>
#include "util.h"
+struct mqueue_fs_context {
+ struct fs_context fc;
+ struct ipc_namespace *ipc_ns;
+};
+
#define MQUEUE_MAGIC 0x19800202
#define DIRENT_SIZE 20
#define FILENT_SIZE 80
@@ -90,6 +96,7 @@ struct mqueue_inode_info {
static const struct inode_operations mqueue_dir_inode_operations;
static const struct file_operations mqueue_file_operations;
static const struct super_operations mqueue_super_ops;
+static const struct fs_context_operations mqueue_fs_context_ops;
static void remove_notification(struct mqueue_inode_info *info);
static struct kmem_cache *mqueue_inode_cachep;
@@ -305,7 +312,7 @@ static struct inode *mqueue_get_inode(struct super_block *sb,
return ERR_PTR(ret);
}
-static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
+static int mqueue_fill_super(struct super_block *sb, struct fs_context *fc)
{
struct inode *inode;
struct ipc_namespace *ns = sb->s_fs_info;
@@ -326,18 +333,28 @@ static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
return 0;
}
-static struct dentry *mqueue_mount(struct file_system_type *fs_type,
- int flags, const char *dev_name,
- void *data)
+static int mqueue_get_tree(struct fs_context *fc)
{
- struct ipc_namespace *ns;
- if (flags & SB_KERNMOUNT) {
- ns = data;
- data = NULL;
- } else {
- ns = current->nsproxy->ipc_ns;
- }
- return mount_ns(fs_type, flags, data, ns, ns->user_ns, mqueue_fill_super);
+ struct mqueue_fs_context *ctx = container_of(fc, struct mqueue_fs_context, fc);
+
+ return mount_ns_fc(fc, mqueue_fill_super, ctx->ipc_ns);
+}
+
+static void mqueue_fs_context_free(struct fs_context *fc)
+{
+ struct mqueue_fs_context *ctx = container_of(fc, struct mqueue_fs_context, fc);
+
+ if (ctx->ipc_ns)
+ put_ipc_ns(ctx->ipc_ns);
+}
+
+static int mqueue_init_fs_context(struct fs_context *fc, struct super_block *src_sb)
+{
+ struct mqueue_fs_context *ctx = container_of(fc, struct mqueue_fs_context, fc);
+
+ ctx->ipc_ns = get_ipc_ns(current->nsproxy->ipc_ns);
+ ctx->fc.ops = &mqueue_fs_context_ops;
+ return 0;
}
static void init_once(void *foo)
@@ -1399,15 +1416,26 @@ static const struct super_operations mqueue_super_ops = {
.statfs = simple_statfs,
};
+static const struct fs_context_operations mqueue_fs_context_ops = {
+ .free = mqueue_fs_context_free,
+ .get_tree = mqueue_get_tree,
+};
+
static struct file_system_type mqueue_fs_type = {
- .name = "mqueue",
- .mount = mqueue_mount,
- .kill_sb = kill_litter_super,
- .fs_flags = FS_USERNS_MOUNT,
+ .name = "mqueue",
+ .fs_context_size = sizeof(struct mqueue_fs_context),
+ .init_fs_context = mqueue_init_fs_context,
+ .kill_sb = kill_litter_super,
+ .fs_flags = FS_USERNS_MOUNT,
};
int mq_init_ns(struct ipc_namespace *ns)
{
+ struct mqueue_fs_context *ctx;
+ struct fs_context *fc;
+ struct vfsmount *mnt;
+ int ret;
+
ns->mq_queues_count = 0;
ns->mq_queues_max = DFLT_QUEUESMAX;
ns->mq_msg_max = DFLT_MSGMAX;
@@ -1415,13 +1443,31 @@ int mq_init_ns(struct ipc_namespace *ns)
ns->mq_msg_default = DFLT_MSG;
ns->mq_msgsize_default = DFLT_MSGSIZE;
- ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns);
- if (IS_ERR(ns->mq_mnt)) {
- int err = PTR_ERR(ns->mq_mnt);
- ns->mq_mnt = NULL;
- return err;
+ fc = vfs_new_fs_context(&mqueue_fs_type, NULL, 0, FS_CONTEXT_FOR_NEW);
+ if (IS_ERR(fc))
+ return PTR_ERR(fc);
+
+ ctx = container_of(fc, struct mqueue_fs_context, fc);
+ if (ctx->ipc_ns != ns) {
+ put_ipc_ns(ctx->ipc_ns);
+ ctx->ipc_ns = get_ipc_ns(ns);
}
- return 0;
+
+ ret = vfs_get_tree(fc);
+ if (ret < 0)
+ goto out_fc;
+
+ mnt = kern_mount_data_fc(fc);
+ if (IS_ERR(mnt)) {
+ ret = PTR_ERR(mnt);
+ goto out_fc;
+ }
+
+ ns->mq_mnt = mnt;
+ ret = 0;
+out_fc:
+ put_fs_context(fc);
+ return ret;
}
void mq_clear_sbinfo(struct ipc_namespace *ns)
[toc] | [prev] | [next] | [standalone]
| From | Al Viro <viro@ZenIV.linux.org.uk> |
|---|---|
| Date | 2017-06-15 12:10 +0200 |
| Subject | Re: [PATCH 25/27] ipc: Convert mqueue fs to fs_context [ver #5] |
| Message-ID | <tSzSV-18C-1@gated-at.bofh.it> |
| In reply to | #1665961 |
On Wed, Jun 14, 2017 at 04:19:03PM +0100, David Howells wrote:
> Convert the mqueue filesystem to use the filesystem context stuff.
>
> Notes:
>
> (1) The relevant ipc namespace is selected in when the context is
> initialised (and it defaults to the current task's ipc namespace).
> The caller can override this before calling vfs_get_tree().
>
> (2) Rather than simply calling kern_mount_data(), mq_init_ns() creates a
> context, adjusts it and then does the rest of the mount procedure.
> + fc = vfs_new_fs_context(&mqueue_fs_type, NULL, 0, FS_CONTEXT_FOR_NEW);
> + if (IS_ERR(fc))
> + return PTR_ERR(fc);
> +
> + ctx = container_of(fc, struct mqueue_fs_context, fc);
Ugh...
> + if (ctx->ipc_ns != ns) {
How could they possibly be equal? You are setting that ns up here, right? How
could it be in any process' nsproxy?
> + put_ipc_ns(ctx->ipc_ns);
> + ctx->ipc_ns = get_ipc_ns(ns);
> + mnt = kern_mount_data_fc(fc);
> + if (IS_ERR(mnt)) {
> + ret = PTR_ERR(mnt);
> + goto out_fc;
> + }
> +
> + ns->mq_mnt = mnt;
> + ret = 0;
> +out_fc:
> + put_fs_context(fc);
Am I right assuming that it's an attempt to cope with "one process starts
setting the things up, passes descriptor to another and buggers off; the
recepient mounts the damn thing and needs something to hold your reference"?
Ugh, again... Is there any reason for dynamic allocation of that thing in
this particular case? AFAICS, these contortions are all due to going through
vfs_new_fs_context()/put_fs_context(). And it's not as if they had been
refcounted...
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-15 16:50 +0200 |
| Subject | Re: [PATCH 25/27] ipc: Convert mqueue fs to fs_context [ver #5] |
| Message-ID | <tSEfT-3Hl-9@gated-at.bofh.it> |
| In reply to | #1666613 |
Al Viro <viro@ZenIV.linux.org.uk> wrote:
> > + if (ctx->ipc_ns != ns) {
>
> How could they possibly be equal? You are setting that ns up here, right?
> How could it be in any process' nsproxy?
Fair point.
> Ugh, again... Is there any reason for dynamic allocation of that thing in
> this particular case? AFAICS, these contortions are all due to going through
> vfs_new_fs_context()/put_fs_context(). And it's not as if they had been
> refcounted...
I can statically initialise it as below, but whilst I don't need to call
vfs_new_fs_context() and put_fs_context(), I do have to call the security
hooks (Smack makes no distinction for internal filesystems) to set up the
security context and clean it up, and I do have to have the error handling for
in case kern_mount_data_fc() fails.
So it actually makes both the source and the object file bigger. Now, I could
hide some of this inside a pair of inline functions, but it doesn't help that
much.
What might be better is to provide a function that wraps the vfs_get_tree()
and kern_mount_data_fc() calls and the cleanup.
David
---
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index f2e1d1d69961..a18a5f6763f9 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -1431,8 +1431,15 @@ static struct file_system_type mqueue_fs_type = {
int mq_init_ns(struct ipc_namespace *ns)
{
- struct mqueue_fs_context *ctx;
- struct fs_context *fc;
+ struct mqueue_fs_context ctx = {
+ .fc.ops = &mqueue_fs_context_ops,
+ .fc.fs_type = &mqueue_fs_type,
+ .fc.cred = current_cred(),
+ .fc.user_ns = current_user_ns(),
+ .fc.purpose = FS_CONTEXT_FOR_NEW,
+ .ipc_ns = ns,
+ };
+ struct super_block *sb;
struct vfsmount *mnt;
int ret;
@@ -1443,29 +1450,32 @@ int mq_init_ns(struct ipc_namespace *ns)
ns->mq_msg_default = DFLT_MSG;
ns->mq_msgsize_default = DFLT_MSGSIZE;
- fc = vfs_new_fs_context(&mqueue_fs_type, NULL, 0, FS_CONTEXT_FOR_NEW);
- if (IS_ERR(fc))
- return PTR_ERR(fc);
-
- ctx = container_of(fc, struct mqueue_fs_context, fc);
- put_ipc_ns(ctx->ipc_ns);
- ctx->ipc_ns = get_ipc_ns(ns);
+ ret = security_fs_context_alloc(&ctx.fc, NULL);
+ if (ret < 0)
+ return ret;
- ret = vfs_get_tree(fc);
+ ret = vfs_get_tree(&ctx.fc);
if (ret < 0)
goto out_fc;
- mnt = kern_mount_data_fc(fc);
+ mnt = kern_mount_data_fc(&ctx.fc);
if (IS_ERR(mnt)) {
ret = PTR_ERR(mnt);
- goto out_fc;
+ goto out_root;
}
ns->mq_mnt = mnt;
ret = 0;
out_fc:
- put_fs_context(fc);
+ security_fs_context_free(&ctx.fc);
return ret;
+
+out_root:
+ sb = ctx.fc.root->d_sb;
+ dput(ctx.fc.root);
+ ctx.fc.root = NULL;
+ deactivate_super(sb);
+ goto out_fc;
}
void mq_clear_sbinfo(struct ipc_namespace *ns)
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 23/27] NFS: Do some tidying of the parsing code [ver #5] |
| Message-ID | <tSifp-6QJ-49@gated-at.bofh.it> |
| In reply to | #1665947 |
Do some tidying of the parsing code, including:
(*) Returning 0/error rather than true/false.
(*) Putting the nfs_fs_context pointer first in some arg lists.
(*) Unwrap some lines that will now fit on one line.
(*) Provide unioned sockaddr/sockaddr_storage fields to avoid casts.
(*) nfs_parse_devname() can paste its return values directly into the
nfs_fs_context struct as that's where the caller puts them.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/nfs/fs_context.c | 128 ++++++++++++++++++++++-----------------------------
fs/nfs/internal.h | 16 ++++--
fs/nfs/super.c | 2 -
3 files changed, 67 insertions(+), 79 deletions(-)
diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
index 763a09b64971..24becb82540f 100644
--- a/fs/nfs/fs_context.c
+++ b/fs/nfs/fs_context.c
@@ -341,8 +341,9 @@ static void nfs_set_mount_transport_protocol(struct nfs_fs_context *ctx)
* Add 'flavor' to 'auth_info' if not already present.
* Returns true if 'flavor' ends up in the list, false otherwise
*/
-static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
- rpc_authflavor_t flavor)
+static int nfs_auth_info_add(struct nfs_fs_context *ctx,
+ struct nfs_auth_info *auth_info,
+ rpc_authflavor_t flavor)
{
unsigned int i;
unsigned int max_flavor_len = ARRAY_SIZE(auth_info->flavors);
@@ -350,26 +351,27 @@ static bool nfs_auth_info_add(struct nfs_auth_info *auth_info,
/* make sure this flavor isn't already in the list */
for (i = 0; i < auth_info->flavor_len; i++) {
if (flavor == auth_info->flavors[i])
- return true;
+ return 0;
}
if (auth_info->flavor_len + 1 >= max_flavor_len) {
dfprintk(MOUNT, "NFS: too many sec= flavors\n");
- return false;
+ return -EINVAL;
}
auth_info->flavors[auth_info->flavor_len++] = flavor;
- return true;
+ return 0;
}
/*
* Parse the value of the 'sec=' option.
*/
-static int nfs_parse_security_flavors(char *value, struct nfs_fs_context *ctx)
+static int nfs_parse_security_flavors(struct nfs_fs_context *ctx, char *value)
{
substring_t args[MAX_OPT_ARGS];
rpc_authflavor_t pseudoflavor;
char *p;
+ int ret;
dfprintk(MOUNT, "NFS: parsing sec=%s option\n", value);
@@ -411,19 +413,20 @@ static int nfs_parse_security_flavors(char *value, struct nfs_fs_context *ctx)
default:
dfprintk(MOUNT,
"NFS: sec= option '%s' not recognized\n", p);
- return 0;
+ return -EINVAL;
}
- if (!nfs_auth_info_add(&ctx->auth_info, pseudoflavor))
- return 0;
+ ret = nfs_auth_info_add(ctx, &ctx->auth_info, pseudoflavor);
+ if (ret < 0)
+ return ret;
}
- return 1;
+ return 0;
}
-static int nfs_parse_version_string(char *string,
- struct nfs_fs_context *ctx,
- substring_t *args)
+static int nfs_parse_version_string(struct nfs_fs_context *ctx,
+ char *string,
+ substring_t *args)
{
ctx->flags &= ~NFS_MOUNT_VER3;
switch (match_token(string, nfs_vers_tokens, args)) {
@@ -454,9 +457,10 @@ static int nfs_parse_version_string(char *string,
ctx->minorversion = 2;
break;
default:
- return 0;
+ dfprintk(MOUNT, "NFS: Unsupported NFS version\n");
+ return -EINVAL;
}
- return 1;
+ return 0;
}
static int nfs_get_option_str(substring_t args[], char **option)
@@ -495,7 +499,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
{
substring_t args[MAX_OPT_ARGS];
char *string;
- int rc, token;
+ int ret, token;
dfprintk(MOUNT, "NFS: parsing nfs mount option '%s'\n", p);
@@ -530,13 +534,11 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
break;
case Opt_lock:
ctx->flags &= ~NFS_MOUNT_NONLM;
- ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK |
- NFS_MOUNT_LOCAL_FCNTL);
+ ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_nolock:
ctx->flags |= NFS_MOUNT_NONLM;
- ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK |
- NFS_MOUNT_LOCAL_FCNTL);
+ ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL);
break;
case Opt_udp:
ctx->flags &= ~NFS_MOUNT_TCP;
@@ -669,29 +671,25 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
- rc = nfs_parse_version_string(string, ctx, args);
+ ret = nfs_parse_version_string(ctx, string, args);
kfree(string);
- if (!rc)
- goto out_invalid_value;
+ if (ret < 0)
+ return ret;
break;
case Opt_sec:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
- rc = nfs_parse_security_flavors(string, ctx);
+ ret = nfs_parse_security_flavors(ctx, string);
kfree(string);
- if (!rc) {
- dfprintk(MOUNT, "NFS: unrecognized "
- "security flavor\n");
- return -EINVAL;
- }
+ if (ret < 0)
+ return ret;
break;
case Opt_proto:
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
- token = match_token(string,
- nfs_xprt_protocol_tokens, args);
+ token = match_token(string, nfs_xprt_protocol_tokens, args);
ctx->protofamily = AF_INET;
switch (token) {
@@ -716,9 +714,8 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
xprt_load_transport(string);
break;
default:
- dfprintk(MOUNT, "NFS: unrecognized "
- "transport protocol\n");
kfree(string);
+ dfprintk(MOUNT, "NFS: unrecognized transport protocol\n");
return -EINVAL;
}
kfree(string);
@@ -727,8 +724,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
- token = match_token(string,
- nfs_xprt_protocol_tokens, args);
+ token = match_token(string, nfs_xprt_protocol_tokens, args);
kfree(string);
ctx->mountfamily = AF_INET;
@@ -745,8 +741,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
break;
case Opt_xprt_rdma: /* not used for side protocols */
default:
- dfprintk(MOUNT, "NFS: unrecognized "
- "transport protocol\n");
+ dfprintk(MOUNT, "NFS: unrecognized transport protocol\n");
return -EINVAL;
}
break;
@@ -756,9 +751,8 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
goto out_nomem;
ctx->nfs_server.addrlen =
rpc_pton(ctx->net, string, strlen(string),
- (struct sockaddr *)
&ctx->nfs_server.address,
- sizeof(ctx->nfs_server.address));
+ sizeof(ctx->nfs_server._address));
kfree(string);
if (ctx->nfs_server.addrlen == 0)
goto out_invalid_address;
@@ -768,8 +762,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
goto out_nomem;
break;
case Opt_mounthost:
- if (nfs_get_option_str(args,
- &ctx->mount_server.hostname))
+ if (nfs_get_option_str(args, &ctx->mount_server.hostname))
goto out_nomem;
break;
case Opt_mountaddr:
@@ -778,9 +771,8 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
goto out_nomem;
ctx->mount_server.addrlen =
rpc_pton(ctx->net, string, strlen(string),
- (struct sockaddr *)
&ctx->mount_server.address,
- sizeof(ctx->mount_server.address));
+ sizeof(ctx->mount_server._address));
kfree(string);
if (ctx->mount_server.addrlen == 0)
goto out_invalid_address;
@@ -789,8 +781,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
- token = match_token(string,
- nfs_lookupcache_tokens, args);
+ token = match_token(string, nfs_lookupcache_tokens, args);
kfree(string);
switch (token) {
case Opt_lookupcache_all:
@@ -804,10 +795,9 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
ctx->flags |= NFS_MOUNT_LOOKUP_CACHE_NONEG|NFS_MOUNT_LOOKUP_CACHE_NONE;
break;
default:
- dfprintk(MOUNT, "NFS: invalid "
- "lookupcache argument\n");
+ dfprintk(MOUNT, "NFS: invalid lookupcache argument\n");
return -EINVAL;
- };
+ }
break;
case Opt_fscache_uniq:
if (nfs_get_option_str(args, &ctx->fscache_uniq))
@@ -818,8 +808,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
string = match_strdup(args);
if (string == NULL)
goto out_nomem;
- token = match_token(string, nfs_local_lock_tokens,
- args);
+ token = match_token(string, nfs_local_lock_tokens, args);
kfree(string);
switch (token) {
case Opt_local_lock_all:
@@ -837,8 +826,7 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
NFS_MOUNT_LOCAL_FCNTL);
break;
default:
- dfprintk(MOUNT, "NFS: invalid "
- "local_lock argument\n");
+ dfprintk(MOUNT, "NFS: invalid local_lock argument\n");
return -EINVAL;
};
break;
@@ -852,13 +840,11 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
break;
case Opt_userspace:
case Opt_deprecated:
- dfprintk(MOUNT, "NFS: ignoring mount option "
- "'%s'\n", p);
+ dfprintk(MOUNT, "NFS: ignoring mount option '%s'\n", p);
break;
default:
- dfprintk(MOUNT, "NFS: unrecognized mount option "
- "'%s'\n", p);
+ dfprintk(MOUNT, "NFS: unrecognized mount option '%s'\n", p);
return -EINVAL;
}
@@ -928,15 +914,15 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
* families in the addr=/mountaddr= options.
*/
if (ctx->protofamily != AF_UNSPEC &&
- ctx->protofamily != ctx->nfs_server.address.ss_family)
+ ctx->protofamily != ctx->nfs_server.address.sa_family)
goto out_proto_mismatch;
if (ctx->mountfamily != AF_UNSPEC) {
if (ctx->mount_server.addrlen) {
- if (ctx->mountfamily != ctx->mount_server.address.ss_family)
+ if (ctx->mountfamily != ctx->mount_server.address.sa_family)
goto out_mountproto_mismatch;
} else {
- if (ctx->mountfamily != ctx->nfs_server.address.ss_family)
+ if (ctx->mountfamily != ctx->nfs_server.address.sa_family)
goto out_mountproto_mismatch;
}
}
@@ -976,9 +962,9 @@ int nfs_parse_mount_options(char *raw, struct nfs_fs_context *ctx)
*
* Note: caller frees hostname and export path, even on error.
*/
-static int nfs_parse_devname(const char *dev_name,
- char **hostname, size_t maxnamlen,
- char **export_path, size_t maxpathlen)
+static int nfs_parse_devname(struct nfs_fs_context *ctx,
+ const char *dev_name,
+ size_t maxnamlen, size_t maxpathlen)
{
size_t len;
char *end;
@@ -1009,17 +995,17 @@ static int nfs_parse_devname(const char *dev_name,
goto out_hostname;
/* N.B. caller will free nfs_server.hostname in all cases */
- *hostname = kstrndup(dev_name, len, GFP_KERNEL);
- if (*hostname == NULL)
+ ctx->nfs_server.hostname = kmemdup_nul(dev_name, len, GFP_KERNEL);
+ if (!ctx->nfs_server.hostname)
goto out_nomem;
len = strlen(++end);
if (len > maxpathlen)
goto out_path;
- *export_path = kstrndup(end, len, GFP_KERNEL);
- if (!*export_path)
+ ctx->nfs_server.export_path = kmemdup_nul(end, len, GFP_KERNEL);
+ if (!ctx->nfs_server.export_path)
goto out_nomem;
- dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", *export_path);
+ dfprintk(MOUNT, "NFS: MNTPATH: '%s'\n", ctx->nfs_server.export_path);
return 0;
out_bad_devname:
@@ -1040,7 +1026,7 @@ static int nfs_parse_devname(const char *dev_name,
}
/*
- * Validate the NFS2/NFS3 mount data
+ * Parse monolithic NFS2/NFS3 mount data
* - fills in the mount root filehandle
*
* For option strings, user space handles the following behaviors:
@@ -1365,11 +1351,7 @@ int nfs_validate_text_mount_data(void *options,
nfs_set_port(sap, &ctx->nfs_server.port, port);
- return nfs_parse_devname(dev_name,
- &ctx->nfs_server.hostname,
- max_namelen,
- &ctx->nfs_server.export_path,
- max_pathlen);
+ return nfs_parse_devname(ctx, dev_name, max_namelen, max_pathlen);
#if !IS_ENABLED(CONFIG_NFS_V4)
out_v4_not_compiled:
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index 1c5404d846cc..fa568407cda8 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -86,11 +86,11 @@ struct nfs_client_initdata {
* In-kernel mount arguments
*/
struct nfs_fs_context {
- int flags;
+ unsigned int flags; /* NFS{,4}_MOUNT_* flags */
unsigned int rsize, wsize;
unsigned int timeo, retrans;
- unsigned int acregmin, acregmax,
- acdirmin, acdirmax;
+ unsigned int acregmin, acregmax;
+ unsigned int acdirmin, acdirmax;
unsigned int namlen;
unsigned int options;
unsigned int bsize;
@@ -106,7 +106,10 @@ struct nfs_fs_context {
bool sloppy;
struct {
- struct sockaddr_storage address;
+ union {
+ struct sockaddr address;
+ struct sockaddr_storage _address;
+ };
size_t addrlen;
char *hostname;
u32 version;
@@ -115,7 +118,10 @@ struct nfs_fs_context {
} mount_server;
struct {
- struct sockaddr_storage address;
+ union {
+ struct sockaddr address;
+ struct sockaddr_storage _address;
+ };
size_t addrlen;
char *hostname;
char *export_path;
diff --git a/fs/nfs/super.c b/fs/nfs/super.c
index 0eb56748f651..c13f0ff42df9 100644
--- a/fs/nfs/super.c
+++ b/fs/nfs/super.c
@@ -795,7 +795,7 @@ static int nfs_request_mount(struct nfs_fs_context *cfg,
/*
* Construct the mount server's address.
*/
- if (cfg->mount_server.address.ss_family == AF_UNSPEC) {
+ if (cfg->mount_server.address.sa_family == AF_UNSPEC) {
memcpy(request.sap, &cfg->nfs_server.address,
cfg->nfs_server.addrlen);
cfg->mount_server.addrlen = cfg->nfs_server.addrlen;
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 22/27] NFS: Add a small buffer in nfs_fs_context to avoid string dup [ver #5] |
| Message-ID | <tSifp-6QJ-57@gated-at.bofh.it> |
| In reply to | #1665947 |
Add a small buffer in nfs_fs_context to avoid string duplication when
parsing numbers. Also make the parsing function wrapper place the parsed
integer directly in the appropriate nfs_fs_context struct member.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/nfs/fs_context.c | 83 ++++++++++++++++++---------------------------------
fs/nfs/internal.h | 2 +
2 files changed, 32 insertions(+), 53 deletions(-)
diff --git a/fs/nfs/fs_context.c b/fs/nfs/fs_context.c
index a2ff9c30ff5a..763a09b64971 100644
--- a/fs/nfs/fs_context.c
+++ b/fs/nfs/fs_context.c
@@ -466,27 +466,22 @@ static int nfs_get_option_str(substring_t args[], char **option)
return !*option;
}
-static int nfs_get_option_ul(substring_t args[], unsigned long *option)
+static int nfs_get_option_ui(struct nfs_fs_context *ctx,
+ substring_t args[], unsigned int *option)
{
- int rc;
- char *string;
-
- string = match_strdup(args);
- if (string == NULL)
- return -ENOMEM;
- rc = kstrtoul(string, 10, option);
- kfree(string);
-
- return rc;
+ match_strlcpy(ctx->buf, args, sizeof(ctx->buf));
+ return kstrtouint(ctx->buf, 10, option);
}
-static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
- unsigned long l_bound, unsigned long u_bound)
+static int nfs_get_option_ui_bound(struct nfs_fs_context *ctx,
+ substring_t args[], unsigned int *option,
+ unsigned int l_bound, unsigned u_bound)
{
int ret;
- ret = nfs_get_option_ul(args, option);
- if (ret != 0)
+ match_strlcpy(ctx->buf, args, sizeof(ctx->buf));
+ ret = kstrtouint(ctx->buf, 10, option);
+ if (ret < 0)
return ret;
if (*option < l_bound || *option > u_bound)
return -ERANGE;
@@ -499,7 +494,6 @@ static int nfs_get_option_ul_bound(substring_t args[], unsigned long *option,
static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
{
substring_t args[MAX_OPT_ARGS];
- unsigned long option;
char *string;
int rc, token;
@@ -507,7 +501,6 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
token = match_token(p, nfs_mount_option_tokens, args);
switch (token) {
-
/*
* boolean options: foo/nofoo
*/
@@ -603,86 +596,70 @@ static int nfs_fs_context_parse_option(struct nfs_fs_context *ctx, char *p)
* options that take numeric values
*/
case Opt_port:
- if (nfs_get_option_ul(args, &option) ||
- option > USHRT_MAX)
+ if (nfs_get_option_ui_bound(ctx, args, &ctx->nfs_server.port,
+ 0, USHRT_MAX))
goto out_invalid_value;
- ctx->nfs_server.port = option;
break;
case Opt_rsize:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->rsize))
goto out_invalid_value;
- ctx->rsize = option;
break;
case Opt_wsize:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->wsize))
goto out_invalid_value;
- ctx->wsize = option;
break;
case Opt_bsize:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->bsize))
goto out_invalid_value;
- ctx->bsize = option;
break;
case Opt_timeo:
- if (nfs_get_option_ul_bound(args, &option, 1, INT_MAX))
+ if (nfs_get_option_ui_bound(ctx, args, &ctx->timeo, 1, INT_MAX))
goto out_invalid_value;
- ctx->timeo = option;
break;
case Opt_retrans:
- if (nfs_get_option_ul_bound(args, &option, 0, INT_MAX))
+ if (nfs_get_option_ui_bound(ctx, args, &ctx->retrans, 0, INT_MAX))
goto out_invalid_value;
- ctx->retrans = option;
break;
case Opt_acregmin:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->acregmin))
goto out_invalid_value;
- ctx->acregmin = option;
break;
case Opt_acregmax:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->acregmax))
goto out_invalid_value;
- ctx->acregmax = option;
break;
case Opt_acdirmin:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->acdirmin))
goto out_invalid_value;
- ctx->acdirmin = option;
break;
case Opt_acdirmax:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->acdirmax))
goto out_invalid_value;
- ctx->acdirmax = option;
break;
case Opt_actimeo:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->acdirmax))
goto out_invalid_value;
ctx->acregmin = ctx->acregmax =
- ctx->acdirmin = ctx->acdirmax = option;
+ ctx->acdirmin = ctx->acdirmax;
break;
case Opt_namelen:
- if (nfs_get_option_ul(args, &option))
+ if (nfs_get_option_ui(ctx, args, &ctx->namlen))
goto out_invalid_value;
- ctx->namlen = option;
break;
case Opt_mountport:
- if (nfs_get_option_ul(args, &option) ||
- option > USHRT_MAX)
+ if (nfs_get_option_ui_bound(ctx, args, &ctx->mount_server.port,
+ 0, USHRT_MAX))
goto out_invalid_value;
- ctx->mount_server.port = option;
break;
case Opt_mountvers:
- if (nfs_get_option_ul(args, &option) ||
- option < NFS_MNT_VERSION ||
- option > NFS_MNT3_VERSION)
+ if (nfs_get_option_ui_bound(ctx, args, &ctx->mount_server.version,
+ NFS_MNT_VERSION, NFS_MNT3_VERSION))
goto out_invalid_value;
- ctx->mount_server.version = option;
break;
case Opt_minorversion:
- if (nfs_get_option_ul(args, &option))
- goto out_invalid_value;
- if (option > NFS4_MAX_MINOR_VERSION)
+ if (nfs_get_option_ui_bound(ctx, args, &ctx->minorversion,
+ 0, NFS4_MAX_MINOR_VERSION))
goto out_invalid_value;
- ctx->minorversion = option;
break;
/*
diff --git a/fs/nfs/internal.h b/fs/nfs/internal.h
index fab0fca9e0ef..1c5404d846cc 100644
--- a/fs/nfs/internal.h
+++ b/fs/nfs/internal.h
@@ -125,6 +125,8 @@ struct nfs_fs_context {
struct security_mnt_opts lsm_opts;
struct net *net;
+
+ char buf[32]; /* Parse buffer */
};
/* mount_clnt.c */
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 14/27] VFS: Add a sample program for fsopen/fsmount [ver #5] |
| Message-ID | <tSifp-6QJ-63@gated-at.bofh.it> |
| In reply to | #1665947 |
Add a sample program for driving fsopen/fsmount.
Signed-off-by: David Howells <dhowells@redhat.com>
---
samples/fsmount/test-fsmount.c | 92 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 92 insertions(+)
create mode 100644 samples/fsmount/test-fsmount.c
diff --git a/samples/fsmount/test-fsmount.c b/samples/fsmount/test-fsmount.c
new file mode 100644
index 000000000000..30caad8e05a3
--- /dev/null
+++ b/samples/fsmount/test-fsmount.c
@@ -0,0 +1,92 @@
+/* fd-based mount test.
+ *
+ * Copyright (C) 2017 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/prctl.h>
+#include <sys/wait.h>
+
+#define PR_ERRMSG_ENABLE 48
+#define PR_ERRMSG_READ 49
+
+#define E(x) do { if ((x) == -1) { perror(#x); exit(1); } } while(0)
+
+static __attribute__((noreturn))
+void mount_error(int fd, const char *s)
+{
+ char buf[4096];
+ int err, n, perr;
+
+ do {
+ err = errno;
+ errno = 0;
+ n = prctl(PR_ERRMSG_READ, buf, sizeof(buf));
+ perr = errno;
+ errno = err;
+ if (n > 0) {
+ fprintf(stderr, "Error: '%s': %*.*s: %m\n", s, n, n, buf);
+ } else {
+ fprintf(stderr, "%s: %m\n", s);
+ }
+ } while (perr == 0);
+ exit(1);
+}
+
+#define E_write(fd, s) \
+ do { \
+ if (write(fd, s, sizeof(s) - 1) == -1) \
+ mount_error(fd, s); \
+ } while (0)
+
+static inline int fsopen(const char *fs_name, int reserved, int flags)
+{
+ return syscall(333, fs_name, reserved, flags);
+}
+
+static inline int fsmount(int fsfd, int dfd, const char *path,
+ unsigned int at_flags, unsigned int flags)
+{
+ return syscall(334, fsfd, dfd, path, at_flags, flags);
+}
+
+int main()
+{
+ int mfd;
+
+ if (prctl(PR_ERRMSG_ENABLE, 1) < 0) {
+ perror("prctl/en");
+ exit(1);
+ }
+
+ /* Mount an NFS filesystem */
+ mfd = fsopen("nfs4", -1, 0);
+ if (mfd == -1) {
+ perror("fsopen");
+ exit(1);
+ }
+
+ E_write(mfd, "s warthog:/data");
+ E_write(mfd, "o fsc");
+ E_write(mfd, "o sync");
+ E_write(mfd, "o intr");
+ E_write(mfd, "o vers=4.2");
+ E_write(mfd, "o addr=90.155.74.18");
+ E_write(mfd, "o clientaddr=90.155.74.21");
+ E_write(mfd, "x create");
+ if (fsmount(mfd, AT_FDCWD, "/mnt", 0, 0) < 0)
+ mount_error(mfd, "fsmount");
+ E(close(mfd));
+
+ exit(0);
+}
[toc] | [prev] | [next] | [standalone]
| From | David Howells <dhowells@redhat.com> |
|---|---|
| Date | 2017-06-14 17:20 +0200 |
| Subject | [PATCH 02/27] VFS: Clean up whitespace in fs/namespace.c and fs/super.c [ver #5] |
| Message-ID | <tSifp-6QJ-65@gated-at.bofh.it> |
| In reply to | #1665947 |
Clean up line terminal whitespace in fs/namespace.c and fs/super.c.
Signed-off-by: David Howells <dhowells@redhat.com>
---
fs/namespace.c | 4 ++--
fs/super.c | 4 ++--
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/fs/namespace.c b/fs/namespace.c
index 8bd3e4d448b9..c076787871e7 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1656,7 +1656,7 @@ void __detach_mounts(struct dentry *dentry)
namespace_unlock();
}
-/*
+/*
* Is the caller allowed to modify his namespace?
*/
static inline bool may_mount(void)
@@ -2210,7 +2210,7 @@ static int do_loopback(struct path *path, const char *old_name,
err = -EINVAL;
if (mnt_ns_loop(old_path.dentry))
- goto out;
+ goto out;
mp = lock_mount(path);
err = PTR_ERR(mp);
diff --git a/fs/super.c b/fs/super.c
index adb0c0de428c..dfb56a9665d8 100644
--- a/fs/super.c
+++ b/fs/super.c
@@ -508,7 +508,7 @@ struct super_block *sget_userns(struct file_system_type *type,
return ERR_PTR(-ENOMEM);
goto retry;
}
-
+
err = set(s, data);
if (err) {
spin_unlock(&sb_lock);
@@ -771,7 +771,7 @@ struct super_block *get_active_super(struct block_device *bdev)
spin_unlock(&sb_lock);
return NULL;
}
-
+
struct super_block *user_get_super(dev_t dev)
{
struct super_block *sb;
[toc] | [prev] | [next] | [standalone]
Page 1 of 3 [1] 2 3 Next page →
Back to top | Article view | linux.kernel
csiph-web