Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]
Groups > linux.kernel > #1674741
| From | Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v2] x86/xen: allow userspace access during hypercalls |
| Date | 2017-06-26 15:00 +0200 |
| Message-ID | <tWBMu-2tb-19@gated-at.bofh.it> (permalink) |
| References | <tWBCO-2pu-45@gated-at.bofh.it> |
| Organization | Invisible Things Lab |
Userspace application can do a hypercall through /dev/xen/privcmd, and
some for some hypercalls argument is a pointers to user-provided
structure. When SMAP is supported and enabled, hypervisor can't access.
So, lets allow it.
The same applies to HYPERVISOR_dm_op, where additionally privcmd driver
carefully verify buffer addresses.
Cc: stable@vger.kernel.org
Signed-off-by: Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com>
---
arch/x86/include/asm/xen/hypercall.h | 9 ++++++++-
1 file changed, 8 insertions(+), 1 deletion(-)
Changes since v1:
- add HYPERVISOR_dm_op
diff --git a/arch/x86/include/asm/xen/hypercall.h b/arch/x86/include/asm/xen/hypercall.h
index f6d20f6..32b74a8 100644
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -43,6 +43,7 @@
#include <asm/page.h>
#include <asm/pgtable.h>
+#include <asm/smap.h>
#include <xen/interface/xen.h>
#include <xen/interface/sched.h>
@@ -214,10 +215,12 @@ privcmd_call(unsigned call,
__HYPERCALL_DECLS;
__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
+ stac();
asm volatile("call *%[call]"
: __HYPERCALL_5PARAM
: [call] "a" (&hypercall_page[call])
: __HYPERCALL_CLOBBER5);
+ clac();
return (long)__res;
}
@@ -476,7 +479,11 @@ static inline int
HYPERVISOR_dm_op(
domid_t dom, unsigned int nr_bufs, void *bufs)
{
- return _hypercall3(int, dm_op, dom, nr_bufs, bufs);
+ int ret;
+ stac();
+ ret = _hypercall3(int, dm_op, dom, nr_bufs, bufs);
+ clac();
+ return ret;
}
static inline void
--
2.7.4
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH] x86/xen: allow userspace access during hypercalls Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> - 2017-06-23 14:50 +0200
Re: [PATCH] x86/xen: allow userspace access during hypercalls Juergen Groß <jgross@suse.com> - 2017-06-26 14:10 +0200
Re: [PATCH] x86/xen: allow userspace access during hypercalls Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> - 2017-06-26 14:50 +0200
Re: [PATCH v2] x86/xen: allow userspace access during hypercalls Juergen Groß <jgross@suse.com> - 2017-06-26 15:00 +0200
[PATCH v2] x86/xen: allow userspace access during hypercalls Marek Marczykowski-Górecki <marmarek@invisiblethingslab.com> - 2017-06-26 15:00 +0200
Re: [PATCH v2] x86/xen: allow userspace access during hypercalls Juergen Gross <jgross@suse.com> - 2017-07-03 13:30 +0200
RE: [Xen-devel] [PATCH] x86/xen: allow userspace access during hypercalls Paul Durrant <Paul.Durrant@citrix.com> - 2017-06-26 15:20 +0200
RE: [Xen-devel] [PATCH] x86/xen: allow userspace access during hypercalls Paul Durrant <Paul.Durrant@citrix.com> - 2017-06-26 15:30 +0200
Re: [Xen-devel] [PATCH] x86/xen: allow userspace access during hypercalls 'Marek Marczykowski-Górecki' <marmarek@invisiblethingslab.com> - 2017-06-26 15:30 +0200
csiph-web