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[RFC][Patch 0/3] securityfs: add the ability to support symlinks

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  [RFC][Patch 0/3] securityfs: add the ability to support symlinks John Johansen <john.johansen@canonical.com> - 2017-05-11 04:50 +0200
    [PATCH 2/3] apparmor: move to per loaddata files, instead of replicating in profiles John Johansen <john.johansen@canonical.com> - 2017-05-11 04:50 +0200

#1639159 — [RFC][Patch 0/3] securityfs: add the ability to support symlinks

Currently securityfs does not support the creation/use of symlinks.

AppArmor would like to be able to use symlinks to map some policy
relationships between profiles and the data set it was loaded from
(patch 2), and to create a specialized magic policy tree that maps
visible policy to the policy namespace that a task is confined by.

The following patchset adds symlink support to securityfs and then
updates apparmor to leverage them.

[toc] | [next] | [standalone]

#1639162 — [PATCH 2/3] apparmor: move to per loaddata files, instead of replicating in profiles

The loaddata sets cover more than just a single profile and should
be tracked at the ns level. Move the load data files under the namespace
and reference the files from the profiles via a symlink.

Signed-off-by: John Johansen <john.johansen@canonical.com>
Reviewed-by: Seth Arnold <seth.arnold@canonical.com>
---
 security/apparmor/apparmorfs.c            | 288 ++++++++++++++++++++++++------
 security/apparmor/include/apparmorfs.h    |   5 +
 security/apparmor/include/policy_ns.h     |   4 +
 security/apparmor/include/policy_unpack.h |  67 ++++++-
 security/apparmor/policy.c                |  42 ++++-
 security/apparmor/policy_ns.c             |   2 +
 security/apparmor/policy_unpack.c         |  49 ++++-
 7 files changed, 393 insertions(+), 64 deletions(-)

diff --git a/security/apparmor/apparmorfs.c b/security/apparmor/apparmorfs.c
index 6d1a4a67abce..5a6010007046 100644
--- a/security/apparmor/apparmorfs.c
+++ b/security/apparmor/apparmorfs.c
@@ -101,10 +101,10 @@ static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf,
 	data = kvmalloc(sizeof(*data) + alloc_size);
 	if (data == NULL)
 		return ERR_PTR(-ENOMEM);
+	memset(data, 0, sizeof(*data));
 	kref_init(&data->count);
+	INIT_LIST_HEAD(&data->list);
 	data->size = copy_size;
-	data->hash = NULL;
-	data->abi = 0;
 
 	if (copy_from_user(data->data, userbuf, copy_size)) {
 		kvfree(data);
@@ -559,68 +559,92 @@ static const struct file_operations aa_fs_ns_name = {
 	.release	= single_release,
 };
 
-static int rawdata_release(struct inode *inode, struct file *file)
+
+/* policy/raw_data/ * file ops */
+
+#define SEQ_RAWDATA_FOPS(NAME)						      \
+static int seq_rawdata_ ##NAME ##_open(struct inode *inode, struct file *file)\
+{									      \
+	return seq_rawdata_open(inode, file, seq_rawdata_ ##NAME ##_show);    \
+}									      \
+									      \
+static const struct file_operations seq_rawdata_ ##NAME ##_fops = {	      \
+	.owner		= THIS_MODULE,					      \
+	.open		= seq_rawdata_ ##NAME ##_open,			      \
+	.read		= seq_read,					      \
+	.llseek		= seq_lseek,					      \
+	.release	= seq_rawdata_release,				      \
+}									      \
+
+static int seq_rawdata_open(struct inode *inode, struct file *file,
+			    int (*show)(struct seq_file *, void *))
 {
-	/* TODO: switch to loaddata when profile switched to symlink */
-	aa_put_loaddata(file->private_data);
+	struct aa_loaddata *data = __aa_get_loaddata(inode->i_private);
+	int error;
 
-	return 0;
+	if (!data)
+		/* lost race this ent is being reaped */
+		return -ENOENT;
+
+	error = single_open(file, show, data);
+	if (error) {
+		file->private_data = NULL;
+		aa_put_loaddata(data);
+	}
+
+	return error;
 }
 
-static int aa_fs_seq_raw_abi_show(struct seq_file *seq, void *v)
+static int seq_rawdata_release(struct inode *inode, struct file *file)
 {
-	struct aa_proxy *proxy = seq->private;
-	struct aa_profile *profile = aa_get_profile_rcu(&proxy->profile);
+	struct seq_file *seq = (struct seq_file *) file->private_data;
 
-	if (profile->rawdata->abi)
-		seq_printf(seq, "v%d\n", profile->rawdata->abi);
+	if (seq)
+		aa_put_loaddata(seq->private);
+	return single_release(inode, file);
+}
 
-	aa_put_profile(profile);
+static int seq_rawdata_abi_show(struct seq_file *seq, void *v)
+{
+	struct aa_loaddata *data = seq->private;
+
+	if (data->abi) {
+		seq_printf(seq, "v%d", data->abi);
+		seq_puts(seq, "\n");
+	}
 
 	return 0;
 }
 
-static int aa_fs_seq_raw_abi_open(struct inode *inode, struct file *file)
+static int seq_rawdata_revision_show(struct seq_file *seq, void *v)
 {
-	return aa_fs_seq_profile_open(inode, file, aa_fs_seq_raw_abi_show);
-}
+	struct aa_loaddata *data = seq->private;
 
-static const struct file_operations aa_fs_seq_raw_abi_fops = {
-	.owner		= THIS_MODULE,
-	.open		= aa_fs_seq_raw_abi_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= aa_fs_seq_profile_release,
-};
+	if (data->revision) {
+		seq_printf(seq, "%ld", data->revision);
+		seq_puts(seq, "\n");
+	}
+
+	return 0;
+}
 
-static int aa_fs_seq_raw_hash_show(struct seq_file *seq, void *v)
+static int seq_rawdata_hash_show(struct seq_file *seq, void *v)
 {
-	struct aa_proxy *proxy = seq->private;
-	struct aa_profile *profile = aa_get_profile_rcu(&proxy->profile);
+	struct aa_loaddata *data = seq->private;
 	unsigned int i, size = aa_hash_size();
 
-	if (profile->rawdata->hash) {
+	if (data->hash) {
 		for (i = 0; i < size; i++)
-			seq_printf(seq, "%.2x", profile->rawdata->hash[i]);
-		seq_putc(seq, '\n');
+			seq_printf(seq, "%.2x", data->hash[i]);
+		seq_puts(seq, "\n");
 	}
-	aa_put_profile(profile);
 
 	return 0;
 }
 
-static int aa_fs_seq_raw_hash_open(struct inode *inode, struct file *file)
-{
-	return aa_fs_seq_profile_open(inode, file, aa_fs_seq_raw_hash_show);
-}
-
-static const struct file_operations aa_fs_seq_raw_hash_fops = {
-	.owner		= THIS_MODULE,
-	.open		= aa_fs_seq_raw_hash_open,
-	.read		= seq_read,
-	.llseek		= seq_lseek,
-	.release	= aa_fs_seq_profile_release,
-};
+SEQ_RAWDATA_FOPS(abi);
+SEQ_RAWDATA_FOPS(revision);
+SEQ_RAWDATA_FOPS(hash);
 
 static ssize_t rawdata_read(struct file *file, char __user *buf, size_t size,
 			    loff_t *ppos)
@@ -631,27 +655,123 @@ static ssize_t rawdata_read(struct file *file, char __user *buf, size_t size,
 				       rawdata->size);
 }
 
+static int rawdata_release(struct inode *inode, struct file *file)
+{
+	aa_put_loaddata(file->private_data);
+
+	return 0;
+}
+
 static int rawdata_open(struct inode *inode, struct file *file)
 {
-	struct aa_proxy *proxy = inode->i_private;
-	struct aa_profile *profile;
+	struct aa_loaddata *rawdata;
 
 	if (!policy_view_capable(NULL))
 		return -EACCES;
-	profile = aa_get_profile_rcu(&proxy->profile);
-	file->private_data = aa_get_loaddata(profile->rawdata);
-	aa_put_profile(profile);
+	rawdata = __aa_get_loaddata(inode->i_private);
+	if (!rawdata)
+		/* lost race: this entry is being reaped */
+		return -ENOENT;
+	file->private_data = rawdata;
 
 	return 0;
 }
 
-static const struct file_operations aa_fs_rawdata_fops = {
+static const struct file_operations rawdata_fops = {
 	.open = rawdata_open,
 	.read = rawdata_read,
 	.llseek = generic_file_llseek,
 	.release = rawdata_release,
 };
 
+static void remove_rawdata_dents(struct aa_loaddata *rawdata)
+{
+	int i;
+
+	for (i = 0; i < AAFS_LOADDATA_NDENTS; i++) {
+		if (!IS_ERR_OR_NULL(rawdata->dents[i])) {
+			/* no refcounts on i_private */
+			securityfs_remove(rawdata->dents[i]);
+			rawdata->dents[i] = NULL;
+		}
+	}
+}
+
+void __aa_fs_remove_rawdata(struct aa_loaddata *rawdata)
+{
+	AA_BUG(rawdata->ns && !mutex_is_locked(&rawdata->ns->lock));
+
+	if (rawdata->ns) {
+		remove_rawdata_dents(rawdata);
+		list_del_init(&rawdata->list);
+		aa_put_ns(rawdata->ns);
+		rawdata->ns = NULL;
+	}
+}
+
+int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata)
+{
+	struct dentry *dent, *dir;
+
+	AA_BUG(!ns);
+	AA_BUG(!rawdata);
+	AA_BUG(!mutex_is_locked(&ns->lock));
+	AA_BUG(!ns_subdata_dir(ns));
+
+	/*
+	 * just use ns revision dir was originally created at. This is
+	 * under ns->lock and if load is successful revision will be
+	 * bumped and is guaranteed to be unique
+	 */
+	rawdata->name = kasprintf(GFP_KERNEL, "%ld", ns->revision);
+	if (!rawdata->name)
+		/* ->name freed when rawdata freed */
+		return -ENOMEM;
+
+	dir = securityfs_create_dir(rawdata->name, ns_subdata_dir(ns));
+	if (IS_ERR(dir))
+		return PTR_ERR(dir);
+	rawdata->dents[AAFS_LOADDATA_DIR] = dir;
+
+	dent = securityfs_create_file("abi", S_IFREG | 0444, dir, rawdata,
+				      &seq_rawdata_abi_fops);
+	if (IS_ERR(dent))
+		goto fail;
+	rawdata->dents[AAFS_LOADDATA_ABI] = dent;
+
+	dent = securityfs_create_file("revision", S_IFREG | 0444, dir, rawdata,
+				      &seq_rawdata_revision_fops);
+	if (IS_ERR(dent))
+		goto fail;
+	rawdata->dents[AAFS_LOADDATA_REVISION] = dent;
+
+	if (aa_g_hash_policy) {
+		dent = securityfs_create_file("sha1", S_IFREG | 0444, dir,
+					      rawdata, &seq_rawdata_hash_fops);
+		if (IS_ERR(dent))
+			goto fail;
+		rawdata->dents[AAFS_LOADDATA_HASH] = dent;
+	}
+
+	dent = securityfs_create_file("raw_data", S_IFREG | 0444,
+				      dir, rawdata, &rawdata_fops);
+	if (IS_ERR(dent))
+		goto fail;
+	rawdata->dents[AAFS_LOADDATA_DATA] = dent;
+	d_inode(dent)->i_size = rawdata->size;
+
+	rawdata->ns = aa_get_ns(ns);
+	list_add(&rawdata->list, &ns->rawdata_list);
+	/* no refcount on inode rawdata */
+
+	return 0;
+
+fail:
+	remove_rawdata_dents(rawdata);
+
+	return PTR_ERR(dent);
+}
+
 /** fns to setup dynamic per profile/namespace files **/
 void __aa_fs_profile_rmdir(struct aa_profile *profile)
 {
@@ -703,7 +823,41 @@ static struct dentry *create_profile_file(struct dentry *dir, const char *name,
 	return dent;
 }
 
-/* requires lock be held */
+static int profile_depth(struct aa_profile *profile)
+{
+	int depth = 0;
+
+	rcu_read_lock();
+	for (depth = 0; profile; profile = rcu_access_pointer(profile->parent))
+		depth++;
+	rcu_read_unlock();
+
+	return depth;
+}
+
+static int gen_symlink_name(char *buffer, size_t bsize, int depth,
+			    const char *dirname, const char *fname)
+{
+	int error;
+
+	for (; depth > 0; depth--) {
+		if (bsize < 7)
+			return -ENAMETOOLONG;
+		strcpy(buffer, "../../");
+		buffer += 6;
+		bsize -= 6;
+	}
+
+	error = snprintf(buffer, bsize, "raw_data/%s/%s", dirname, fname);
+	if (error >= bsize || error < 0)
+		return -ENAMETOOLONG;
+
+	return 0;
+}
+
+/*
+ * Requires: @profile->ns->lock held
+ */
 int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
 {
 	struct aa_profile *child;
@@ -764,26 +918,34 @@ int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
 	}
 
 	if (profile->rawdata) {
-		dent = create_profile_file(dir, "raw_sha1", profile,
-					   &aa_fs_seq_raw_hash_fops);
+		char target[64];
+		int depth = profile_depth(profile);
+		error = gen_symlink_name(target, sizeof(target), depth,
+					 profile->rawdata->name, "sha1");
+		if (error < 0)
+			goto fail2;
+		dent = securityfs_create_symlink("raw_sha1", dir, target, NULL);
 		if (IS_ERR(dent))
 			goto fail;
 		profile->dents[AAFS_PROF_RAW_HASH] = dent;
 
-		dent = create_profile_file(dir, "raw_abi", profile,
-					   &aa_fs_seq_raw_abi_fops);
+		error = gen_symlink_name(target, sizeof(target), depth,
+					 profile->rawdata->name, "abi");
+		if (error < 0)
+			goto fail2;
+		dent = securityfs_create_symlink("raw_abi", dir, target, NULL);
 		if (IS_ERR(dent))
 			goto fail;
 		profile->dents[AAFS_PROF_RAW_ABI] = dent;
 
-		dent = securityfs_create_file("raw_data", S_IFREG | 0444, dir,
-					      profile->proxy,
-					      &aa_fs_rawdata_fops);
+		error = gen_symlink_name(target, sizeof(target), depth,
+					 profile->rawdata->name, "raw_data");
+		if (error < 0)
+			goto fail2;
+		dent = securityfs_create_symlink("raw_data", dir, target, NULL);
 		if (IS_ERR(dent))
 			goto fail;
 		profile->dents[AAFS_PROF_RAW_DATA] = dent;
-		d_inode(dent)->i_size = profile->rawdata->size;
-		aa_get_proxy(profile->proxy);
 	}
 
 	list_for_each_entry(child, &profile->base.profiles, base.list) {
@@ -803,6 +965,16 @@ int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
 	return error;
 }
 
+static void __aa_fs_list_remove_rawdata(struct aa_ns *ns)
+{
+	struct aa_loaddata *ent, *tmp;
+
+	AA_BUG(!mutex_is_locked(&ns->lock));
+
+	list_for_each_entry_safe(ent, tmp, &ns->rawdata_list, list)
+		__aa_fs_remove_rawdata(ent);
+}
+
 void __aa_fs_ns_rmdir(struct aa_ns *ns)
 {
 	struct aa_ns *sub;
@@ -821,6 +993,8 @@ void __aa_fs_ns_rmdir(struct aa_ns *ns)
 		mutex_unlock(&sub->lock);
 	}
 
+	__aa_fs_list_remove_rawdata(ns);
+
 	if (ns_subns_dir(ns)) {
 		sub = d_inode(ns_subns_dir(ns))->i_private;
 		aa_put_ns(sub);
diff --git a/security/apparmor/include/apparmorfs.h b/security/apparmor/include/apparmorfs.h
index 120a798b5bb0..0b6d32b3f05e 100644
--- a/security/apparmor/include/apparmorfs.h
+++ b/security/apparmor/include/apparmorfs.h
@@ -106,6 +106,7 @@ enum aafs_prof_type {
 #define prof_dir(X) ((X)->dents[AAFS_PROF_DIR])
 #define prof_child_dir(X) ((X)->dents[AAFS_PROF_PROFS])
 
+void __aa_bump_ns_revision(struct aa_ns *ns);
 void __aa_fs_profile_rmdir(struct aa_profile *profile);
 void __aa_fs_profile_migrate_dents(struct aa_profile *old,
 				   struct aa_profile *new);
@@ -114,4 +115,8 @@ void __aa_fs_ns_rmdir(struct aa_ns *ns);
 int __aa_fs_ns_mkdir(struct aa_ns *ns, struct dentry *parent,
 		     const char *name);
 
+struct aa_loaddata;
+void __aa_fs_remove_rawdata(struct aa_loaddata *rawdata);
+int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata);
+
 #endif /* __AA_APPARMORFS_H */
diff --git a/security/apparmor/include/policy_ns.h b/security/apparmor/include/policy_ns.h
index 89cffddd7e75..23e7cb770226 100644
--- a/security/apparmor/include/policy_ns.h
+++ b/security/apparmor/include/policy_ns.h
@@ -68,6 +68,10 @@ struct aa_ns {
 	atomic_t uniq_null;
 	long uniq_id;
 	int level;
+	long revision;
+	wait_queue_head_t wait;
+
+	struct list_head rawdata_list;
 
 	struct dentry *dents[AAFS_NS_SIZEOF];
 };
diff --git a/security/apparmor/include/policy_unpack.h b/security/apparmor/include/policy_unpack.h
index 4c1319eebc42..6c349cf69590 100644
--- a/security/apparmor/include/policy_unpack.h
+++ b/security/apparmor/include/policy_unpack.h
@@ -17,6 +17,8 @@
 
 #include <linux/list.h>
 #include <linux/kref.h>
+#include <linux/dcache.h>
+#include <linux/workqueue.h>
 
 struct aa_load_ent {
 	struct list_head list;
@@ -36,25 +38,82 @@ struct aa_load_ent *aa_load_ent_alloc(void);
 #define PACKED_MODE_KILL	2
 #define PACKED_MODE_UNCONFINED	3
 
-/* struct aa_loaddata - buffer of policy load data set */
+struct aa_ns;
+
+enum {
+	AAFS_LOADDATA_ABI = 0,
+	AAFS_LOADDATA_REVISION,
+	AAFS_LOADDATA_HASH,
+	AAFS_LOADDATA_DATA,
+	AAFS_LOADDATA_DIR,		/* must be last actual entry */
+	AAFS_LOADDATA_NDENTS		/* count of entries */
+};
+
+/*
+ * struct aa_loaddata - buffer of policy raw_data set
+ *
+ * there is no loaddata ref for being on ns list, nor a ref from
+ * d_inode(@dentry) when grab a ref from these, @ns->lock must be held
+ * && __aa_get_loaddata() needs to be used, and the return value
+ * checked, if NULL the loaddata is already being reaped and should be
+ * considered dead.
+*/
 struct aa_loaddata {
 	struct kref count;
+	struct list_head list;
+	struct work_struct work;
+	struct dentry *dents[AAFS_LOADDATA_NDENTS];
+	struct aa_ns *ns;
+	char *name;
 	size_t size;
+	long revision;			/* the ns policy revision this caused */
 	int abi;
 	unsigned char *hash;
+
 	char data[];
 };
 
 int aa_unpack(struct aa_loaddata *udata, struct list_head *lh, const char **ns);
 
 static inline struct aa_loaddata *
+/**
+ * __aa_get_loaddata - get a reference count to uncounted data reference
+ * @data: reference to get a count on
+ *
+ * Returns: pointer to reference OR NULL if race is lost and reference is
+ *          being repeated.
+ * Requires: @data->ns->lock held, and the return code MUST be checked
+ *
+ * Use only from inode->i_private and @data->list found references
+ */
+__aa_get_loaddata(struct aa_loaddata *data)
+{
+	if (data && kref_get_not0(&(data->count)))
+		return data;
+
+	return NULL;
+}
+
+/**
+ * aa_get_loaddata - get a reference count from a counted data reference
+ * @data: reference to get a count on
+ *
+ * Returns: point to reference
+ * Requires: @data to have a valid reference count on it. It is a bug
+ *           if the race to reap can be encountered when it is used.
+ */
+static inline struct aa_loaddata *
 aa_get_loaddata(struct aa_loaddata *data)
 {
-	if (data)
-		kref_get(&(data->count));
-	return data;
+	struct aa_loaddata *tmp = __aa_get_loaddata(data);
+
+	AA_BUG(data && !tmp);
+
+	return tmp;
 }
 
+void __aa_loaddata_update(struct aa_loaddata *data, long revision);
+bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r);
 void aa_loaddata_kref(struct kref *kref);
 static inline void aa_put_loaddata(struct aa_loaddata *data)
 {
diff --git a/security/apparmor/policy.c b/security/apparmor/policy.c
index c0a4066ddfb2..27e39dd278f6 100644
--- a/security/apparmor/policy.c
+++ b/security/apparmor/policy.c
@@ -838,6 +838,7 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
 	const char *ns_name, *info = NULL;
 	struct aa_ns *ns = NULL;
 	struct aa_load_ent *ent, *tmp;
+	struct aa_loaddata *rawdata_ent;
 	const char *op = OP_PROF_REPL;
 	ssize_t count, error;
 	LIST_HEAD(lh);
@@ -885,6 +886,20 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
 		ns = aa_get_ns(view);
 
 	mutex_lock(&ns->lock);
+	/* check for duplicate rawdata blobs: space and file dedup */
+	list_for_each_entry(rawdata_ent, &ns->rawdata_list, list) {
+		if (aa_rawdata_eq(rawdata_ent, udata)) {
+			struct aa_loaddata *tmp;
+
+			tmp = __aa_get_loaddata(rawdata_ent);
+			/* check we didn't fail the race */
+			if (tmp) {
+				aa_put_loaddata(udata);
+				udata = tmp;
+				break;
+			}
+		}
+	}
 	/* setup parent and ns info */
 	list_for_each_entry(ent, &lh, list) {
 		struct aa_policy *policy;
@@ -927,6 +942,14 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
 	}
 
 	/* create new fs entries for introspection if needed */
+	if (!udata->dents[AAFS_LOADDATA_DIR]) {
+		error = __aa_fs_create_rawdata(ns, udata);
+		if (error) {
+			info = "failed to create raw_data dir and files";
+			ent = NULL;
+			goto fail_lock;
+		}
+	}
 	list_for_each_entry(ent, &lh, list) {
 		if (ent->old) {
 			/* inherit old interface files */
@@ -953,10 +976,24 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
 	}
 
 	/* Done with checks that may fail - do actual replacement */
+	__aa_bump_ns_revision(ns);
+	__aa_loaddata_update(udata, ns->revision);
 	list_for_each_entry_safe(ent, tmp, &lh, list) {
 		list_del_init(&ent->list);
 		op = (!ent->old && !ent->rename) ? OP_PROF_LOAD : OP_PROF_REPL;
 
+		if (ent->old && ent->old->rawdata == ent->new->rawdata) {
+			/* dedup actual profile replacement */
+			audit_policy(profile, op, ns_name, ent->new->base.hname,
+				     "same as current profile, skipping",
+				     error);
+			goto skip;
+		}
+
+		/*
+		 * TODO: finer dedup based on profile range in data. Load set
+		 * can differ but profile may remain unchanged
+		 */
 		audit_policy(profile, op, NULL, ent->new->base.hname,
 			     NULL, error);
 
@@ -996,6 +1033,7 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
 					   aa_get_profile(ent->new));
 			__list_add_profile(&ns->base.profiles, ent->new);
 		}
+	skip:
 		aa_load_ent_free(ent);
 	}
 	mutex_unlock(&ns->lock);
@@ -1011,7 +1049,7 @@ ssize_t aa_replace_profiles(struct aa_ns *view, struct aa_profile *profile,
 	mutex_unlock(&ns->lock);
 
 	/* audit cause of failure */
-	op = (!ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
+	op = (ent && !ent->old) ? OP_PROF_LOAD : OP_PROF_REPL;
 fail:
 	audit_policy(profile, op, ns_name, ent ? ent->new->base.hname : NULL,
 		     info, error);
@@ -1083,6 +1121,7 @@ ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_profile *subj,
 		/* remove namespace - can only happen if fqname[0] == ':' */
 		mutex_lock(&ns->parent->lock);
 		__aa_remove_ns(ns);
+		__aa_bump_ns_revision(ns);
 		mutex_unlock(&ns->parent->lock);
 	} else {
 		/* remove profile */
@@ -1095,6 +1134,7 @@ ssize_t aa_remove_profiles(struct aa_ns *view, struct aa_profile *subj,
 		}
 		name = profile->base.hname;
 		__remove_profile(profile);
+		__aa_bump_ns_revision(ns);
 		mutex_unlock(&ns->lock);
 	}
 
diff --git a/security/apparmor/policy_ns.c b/security/apparmor/policy_ns.c
index 93d1826c4b09..e08ad92471a6 100644
--- a/security/apparmor/policy_ns.c
+++ b/security/apparmor/policy_ns.c
@@ -99,7 +99,9 @@ static struct aa_ns *alloc_ns(const char *prefix, const char *name)
 		goto fail_ns;
 
 	INIT_LIST_HEAD(&ns->sub_ns);
+	INIT_LIST_HEAD(&ns->rawdata_list);
 	mutex_init(&ns->lock);
+	init_waitqueue_head(&ns->wait);
 
 	/* released by aa_free_ns() */
 	ns->unconfined = aa_alloc_profile("unconfined", GFP_KERNEL);
diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c
index 2e37c9c26bbd..54a0d2c44de4 100644
--- a/security/apparmor/policy_unpack.c
+++ b/security/apparmor/policy_unpack.c
@@ -122,13 +122,58 @@ static int audit_iface(struct aa_profile *new, const char *ns_name,
 	return aa_audit(AUDIT_APPARMOR_STATUS, profile, &sa, audit_cb);
 }
 
+void __aa_loaddata_update(struct aa_loaddata *data, long revision)
+{
+	AA_BUG(!data);
+	AA_BUG(!data->ns);
+	AA_BUG(!data->dents[AAFS_LOADDATA_REVISION]);
+	AA_BUG(!mutex_is_locked(&data->ns->lock));
+	AA_BUG(data->revision > revision);
+
+	data->revision = revision;
+	d_inode(data->dents[AAFS_LOADDATA_DIR])->i_mtime =
+		current_time(d_inode(data->dents[AAFS_LOADDATA_DIR]));
+	d_inode(data->dents[AAFS_LOADDATA_REVISION])->i_mtime =
+		current_time(d_inode(data->dents[AAFS_LOADDATA_REVISION]));
+}
+
+bool aa_rawdata_eq(struct aa_loaddata *l, struct aa_loaddata *r)
+{
+	if (l->size != r->size)
+		return false;
+	if (aa_g_hash_policy && memcmp(l->hash, r->hash, aa_hash_size()) != 0)
+		return false;
+	return memcmp(l->data, r->data, r->size) == 0;
+}
+
+/*
+ * need to take the ns mutex lock which is NOT safe most places that
+ * put_loaddata is called, so we have to delay freeing it
+ */
+static void do_loaddata_free(struct work_struct *work)
+{
+	struct aa_loaddata *d = container_of(work, struct aa_loaddata, work);
+	struct aa_ns *ns = aa_get_ns(d->ns);
+
+	if (ns) {
+		mutex_lock(&ns->lock);
+		__aa_fs_remove_rawdata(d);
+		mutex_unlock(&ns->lock);
+		aa_put_ns(ns);
+	}
+
+	kzfree(d->hash);
+	kfree(d->name);
+	kvfree(d);
+}
+
 void aa_loaddata_kref(struct kref *kref)
 {
 	struct aa_loaddata *d = container_of(kref, struct aa_loaddata, count);
 
 	if (d) {
-		kzfree(d->hash);
-		kvfree(d);
+		INIT_WORK(&d->work, do_loaddata_free);
+		schedule_work(&d->work);
 	}
 }
 
-- 
2.11.0

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