* [PATCH v3] drm/i915: bounds check execbuffer relocation count
@ 2013-03-12 0:31 Kees Cook
2013-03-12 9:07 ` Chris Wilson
0 siblings, 1 reply; 6+ messages in thread
From: Kees Cook @ 2013-03-12 0:31 UTC (permalink / raw)
To: linux-kernel
Cc: Daniel Vetter, David Airlie, dri-devel, intel-gfx, Julien Tinnes,
marcheu
It is possible to wrap the counter used to allocate the buffer for
relocation copies. This could lead to heap writing overflows.
CVE-2013-0913
v3: collapse test, improve comment
v2: move check into validate_exec_list
Signed-off-by: Kees Cook <keescook@chromium.org>
Reported-by: Pinkie Pie
Cc: stable@vger.kernel.org
---
drivers/gpu/drm/i915/i915_gem_execbuffer.c | 11 ++++++++---
1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index b3a40ee..094ba41 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -732,6 +732,8 @@ validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
int count)
{
int i;
+ int relocs_total = 0;
+ int relocs_max = INT_MAX / sizeof(struct drm_i915_gem_relocation_entry);
for (i = 0; i < count; i++) {
char __user *ptr = (char __user *)(uintptr_t)exec[i].relocs_ptr;
@@ -740,10 +742,13 @@ validate_exec_list(struct drm_i915_gem_exec_object2 *exec,
if (exec[i].flags & __EXEC_OBJECT_UNKNOWN_FLAGS)
return -EINVAL;
- /* First check for malicious input causing overflow */
- if (exec[i].relocation_count >
- INT_MAX / sizeof(struct drm_i915_gem_relocation_entry))
+ /* First check for malicious input causing overflow in
+ * the worst case where we need to allocate the entire
+ * relocation tree as a single array.
+ */
+ if (exec[i].relocation_count > relocs_max - relocs_total)
return -EINVAL;
+ relocs_total += exec[i].relocation_count;
length = exec[i].relocation_count *
sizeof(struct drm_i915_gem_relocation_entry);
--
1.7.9.5
--
Kees Cook
Chrome OS Security
^ permalink raw reply related [flat|nested] 6+ messages in thread* Re: [PATCH v3] drm/i915: bounds check execbuffer relocation count
2013-03-12 0:31 [PATCH v3] drm/i915: bounds check execbuffer relocation count Kees Cook
@ 2013-03-12 9:07 ` Chris Wilson
2013-03-13 20:28 ` Daniel Vetter
0 siblings, 1 reply; 6+ messages in thread
From: Chris Wilson @ 2013-03-12 9:07 UTC (permalink / raw)
To: Kees Cook
Cc: linux-kernel, Daniel Vetter, David Airlie, dri-devel, intel-gfx,
Julien Tinnes, marcheu
On Mon, Mar 11, 2013 at 05:31:45PM -0700, Kees Cook wrote:
> It is possible to wrap the counter used to allocate the buffer for
> relocation copies. This could lead to heap writing overflows.
>
> CVE-2013-0913
>
> v3: collapse test, improve comment
> v2: move check into validate_exec_list
>
> Signed-off-by: Kees Cook <keescook@chromium.org>
> Reported-by: Pinkie Pie
> Cc: stable@vger.kernel.org
Looks good to me. The only bikeshed that remains is whether we should
just collapse the two variables into one, but the current 'max - count'
is more idiomatic and so preferrable.
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
-Chris
--
Chris Wilson, Intel Open Source Technology Centre
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] drm/i915: bounds check execbuffer relocation count
2013-03-12 9:07 ` Chris Wilson
@ 2013-03-13 20:28 ` Daniel Vetter
2013-03-14 16:57 ` Daniel Vetter
0 siblings, 1 reply; 6+ messages in thread
From: Daniel Vetter @ 2013-03-13 20:28 UTC (permalink / raw)
To: Chris Wilson, Kees Cook, linux-kernel, Daniel Vetter,
David Airlie, dri-devel, intel-gfx, Julien Tinnes, marcheu
On Tue, Mar 12, 2013 at 09:07:46AM +0000, Chris Wilson wrote:
> On Mon, Mar 11, 2013 at 05:31:45PM -0700, Kees Cook wrote:
> > It is possible to wrap the counter used to allocate the buffer for
> > relocation copies. This could lead to heap writing overflows.
> >
> > CVE-2013-0913
> >
> > v3: collapse test, improve comment
> > v2: move check into validate_exec_list
> >
> > Signed-off-by: Kees Cook <keescook@chromium.org>
> > Reported-by: Pinkie Pie
> > Cc: stable@vger.kernel.org
>
> Looks good to me. The only bikeshed that remains is whether we should
> just collapse the two variables into one, but the current 'max - count'
> is more idiomatic and so preferrable.
> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Picked up for -fixes, thanks for the patch.
-Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] drm/i915: bounds check execbuffer relocation count
2013-03-13 20:28 ` Daniel Vetter
@ 2013-03-14 16:57 ` Daniel Vetter
2013-03-14 19:32 ` Kees Cook
0 siblings, 1 reply; 6+ messages in thread
From: Daniel Vetter @ 2013-03-14 16:57 UTC (permalink / raw)
To: Chris Wilson, Kees Cook, linux-kernel, Daniel Vetter,
David Airlie, dri-devel, intel-gfx, Julien Tinnes, marcheu
On Wed, Mar 13, 2013 at 9:28 PM, Daniel Vetter <daniel@ffwll.ch> wrote:
> On Tue, Mar 12, 2013 at 09:07:46AM +0000, Chris Wilson wrote:
>> On Mon, Mar 11, 2013 at 05:31:45PM -0700, Kees Cook wrote:
>> > It is possible to wrap the counter used to allocate the buffer for
>> > relocation copies. This could lead to heap writing overflows.
>> >
>> > CVE-2013-0913
>> >
>> > v3: collapse test, improve comment
>> > v2: move check into validate_exec_list
>> >
>> > Signed-off-by: Kees Cook <keescook@chromium.org>
>> > Reported-by: Pinkie Pie
>> > Cc: stable@vger.kernel.org
>>
>> Looks good to me. The only bikeshed that remains is whether we should
>> just collapse the two variables into one, but the current 'max - count'
>> is more idiomatic and so preferrable.
>> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
>
> Picked up for -fixes, thanks for the patch.
I've forgotten to dump my wishlist: Can I have an i-g-t for this? For
this bug here specifically an execbuf with just one buffer with too
many relocs plus another execbuf with two buffers with relocation so
that the 2nd relocation list will overflow should be sufficient.
Cheers, Daniel
--
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH v3] drm/i915: bounds check execbuffer relocation count
2013-03-14 16:57 ` Daniel Vetter
@ 2013-03-14 19:32 ` Kees Cook
2013-03-15 12:32 ` [Intel-gfx] " Damien Lespiau
0 siblings, 1 reply; 6+ messages in thread
From: Kees Cook @ 2013-03-14 19:32 UTC (permalink / raw)
To: Daniel Vetter
Cc: Chris Wilson, LKML, David Airlie, dri-devel, intel-gfx,
Julien Tinnes, marcheu
On Thu, Mar 14, 2013 at 9:57 AM, Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
> On Wed, Mar 13, 2013 at 9:28 PM, Daniel Vetter <daniel@ffwll.ch> wrote:
>> On Tue, Mar 12, 2013 at 09:07:46AM +0000, Chris Wilson wrote:
>>> On Mon, Mar 11, 2013 at 05:31:45PM -0700, Kees Cook wrote:
>>> > It is possible to wrap the counter used to allocate the buffer for
>>> > relocation copies. This could lead to heap writing overflows.
>>> >
>>> > CVE-2013-0913
>>> >
>>> > v3: collapse test, improve comment
>>> > v2: move check into validate_exec_list
>>> >
>>> > Signed-off-by: Kees Cook <keescook@chromium.org>
>>> > Reported-by: Pinkie Pie
>>> > Cc: stable@vger.kernel.org
>>>
>>> Looks good to me. The only bikeshed that remains is whether we should
>>> just collapse the two variables into one, but the current 'max - count'
>>> is more idiomatic and so preferrable.
>>> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
>>
>> Picked up for -fixes, thanks for the patch.
>
> I've forgotten to dump my wishlist: Can I have an i-g-t for this? For
> this bug here specifically an execbuf with just one buffer with too
> many relocs plus another execbuf with two buffers with relocation so
> that the 2nd relocation list will overflow should be sufficient.
Sure thing. Where do these live? (Or what docs should I read for
this?) I'm assuming i-g-t means "intel graphics test"? :)
-Kees
--
Kees Cook
Chrome OS Security
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [Intel-gfx] [PATCH v3] drm/i915: bounds check execbuffer relocation count
2013-03-14 19:32 ` Kees Cook
@ 2013-03-15 12:32 ` Damien Lespiau
0 siblings, 0 replies; 6+ messages in thread
From: Damien Lespiau @ 2013-03-15 12:32 UTC (permalink / raw)
To: Kees Cook
Cc: Daniel Vetter, Julien Tinnes, David Airlie, intel-gfx, LKML,
dri-devel
On Thu, Mar 14, 2013 at 12:32:00PM -0700, Kees Cook wrote:
> On Thu, Mar 14, 2013 at 9:57 AM, Daniel Vetter <daniel.vetter@ffwll.ch> wrote:
> > On Wed, Mar 13, 2013 at 9:28 PM, Daniel Vetter <daniel@ffwll.ch> wrote:
> >> On Tue, Mar 12, 2013 at 09:07:46AM +0000, Chris Wilson wrote:
> >>> On Mon, Mar 11, 2013 at 05:31:45PM -0700, Kees Cook wrote:
> >>> > It is possible to wrap the counter used to allocate the buffer for
> >>> > relocation copies. This could lead to heap writing overflows.
> >>> >
> >>> > CVE-2013-0913
> >>> >
> >>> > v3: collapse test, improve comment
> >>> > v2: move check into validate_exec_list
> >>> >
> >>> > Signed-off-by: Kees Cook <keescook@chromium.org>
> >>> > Reported-by: Pinkie Pie
> >>> > Cc: stable@vger.kernel.org
> >>>
> >>> Looks good to me. The only bikeshed that remains is whether we should
> >>> just collapse the two variables into one, but the current 'max - count'
> >>> is more idiomatic and so preferrable.
> >>> Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
> >>
> >> Picked up for -fixes, thanks for the patch.
> >
> > I've forgotten to dump my wishlist: Can I have an i-g-t for this? For
> > this bug here specifically an execbuf with just one buffer with too
> > many relocs plus another execbuf with two buffers with relocation so
> > that the 2nd relocation list will overflow should be sufficient.
>
> Sure thing. Where do these live? (Or what docs should I read for
> this?) I'm assuming i-g-t means "intel graphics test"? :)
Close :) GPU Tools. The tests lives in the tests directory of:
http://cgit.freedesktop.org/xorg/app/intel-gpu-tools/
--
Damien
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2013-03-15 12:32 UTC | newest]
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2013-03-12 0:31 [PATCH v3] drm/i915: bounds check execbuffer relocation count Kees Cook
2013-03-12 9:07 ` Chris Wilson
2013-03-13 20:28 ` Daniel Vetter
2013-03-14 16:57 ` Daniel Vetter
2013-03-14 19:32 ` Kees Cook
2013-03-15 12:32 ` [Intel-gfx] " Damien Lespiau
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