All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH] drm: fix send_vblank_event use-after-free error
@ 2016-06-20 16:42 Matthew Auld
  2016-06-20 17:17 ` ✗ Ro.CI.BAT: warning for " Patchwork
  2016-06-20 19:18 ` [PATCH] " Daniel Vetter
  0 siblings, 2 replies; 3+ messages in thread
From: Matthew Auld @ 2016-06-20 16:42 UTC (permalink / raw)
  To: intel-gfx; +Cc: Daniel Vetter, dri-devel

The drm_pending_event can be freed by drm_send_event_locked, as a
result we should call trace_drm_vblank_event_delivered before this
to avoid hitting a user-after-free error when accessing the pid member:

[  378.438497] BUG: KASAN: use-after-free in send_vblank_event+0xf0/0x310 [drm] at addr ffff8801ac7e50a0
[  378.438500] Read of size 4 by task Xorg/1562
[  378.438501] =============================================================================
[  378.438504] BUG kmalloc-128 (Tainted: G    B          ): kasan: bad access detected
[  378.438506] -----------------------------------------------------------------------------

[  378.438509] INFO: Freed in 0x10001309c age=18446737369265680575 cpu=0 pid=0
[  378.438541]  drm_send_event_locked+0x207/0x2f0 [drm]
[  378.438544]  __slab_free+0x24c/0x650
[  378.438546]  kfree+0x3a2/0x760
[  378.438578]  drm_send_event_locked+0x207/0x2f0 [drm]
[  378.438610]  send_vblank_event+0xb7/0x310 [drm]
[  378.438643]  drm_crtc_send_vblank_event+0x130/0x1f0 [drm]
[  378.438722]  intel_atomic_commit_tail+0x23b5/0x53f0 [i915]
[  378.438802]  intel_atomic_commit+0xbae/0x12f0 [i915]
[  378.438839]  drm_atomic_commit+0xb0/0x120 [drm]
[  378.438855]  drm_atomic_helper_connector_dpms+0x339/0x5d0 [drm_kms_helper]
[  378.438891]  drm_mode_obj_set_property_ioctl+0x8f1/0xcc0 [drm]
[  378.438927]  drm_mode_connector_property_set_ioctl+0xf3/0x170 [drm]
[  378.438959]  drm_ioctl+0x2d7/0xae0 [drm]
[  378.438962]  do_vfs_ioctl+0x1c9/0x1280
[  378.438964]  SyS_ioctl+0x79/0x90
[  378.438967]  entry_SYSCALL_64_fastpath+0x1a/0xa4

Cc: dri-devel@lists.freedesktop.org
Cc: Daniel Vetter <daniel.vetter@intel.com>
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
---
 drivers/gpu/drm/drm_irq.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 76e39c5..8ca3d2b 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -994,10 +994,10 @@ static void send_vblank_event(struct drm_device *dev,
 	e->event.tv_sec = now->tv_sec;
 	e->event.tv_usec = now->tv_usec;
 
-	drm_send_event_locked(dev, &e->base);
-
 	trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
 					 e->event.sequence);
+
+	drm_send_event_locked(dev, &e->base);
 }
 
 /**
-- 
2.5.5

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply related	[flat|nested] 3+ messages in thread
* ✗ Ro.CI.BAT: warning for drm: fix send_vblank_event use-after-free error
  2016-06-20 16:42 [PATCH] drm: fix send_vblank_event use-after-free error Matthew Auld
@ 2016-06-20 17:17 ` Patchwork
  2016-06-20 19:18 ` [PATCH] " Daniel Vetter
  1 sibling, 0 replies; 3+ messages in thread
From: Patchwork @ 2016-06-20 17:17 UTC (permalink / raw)
  To: Matthew Auld; +Cc: intel-gfx

== Series Details ==

Series: drm: fix send_vblank_event use-after-free error
URL   : https://patchwork.freedesktop.org/series/8939/
State : warning

== Summary ==

Series 8939v1 drm: fix send_vblank_event use-after-free error
http://patchwork.freedesktop.org/api/1.0/series/8939/revisions/1/mbox

Test kms_pipe_crc_basic:
        Subgroup suspend-read-crc-pipe-b:
                skip       -> DMESG-WARN (ro-bdw-i5-5250u)
        Subgroup suspend-read-crc-pipe-c:
                skip       -> DMESG-WARN (ro-bdw-i5-5250u)

ro-bdw-i5-5250u  total:223  pass:195  dwarn:3   dfail:0   fail:2   skip:23 
ro-bdw-i7-5600u  total:223  pass:183  dwarn:0   dfail:0   fail:2   skip:38 
ro-bsw-n3050     total:223  pass:170  dwarn:0   dfail:0   fail:4   skip:49 
ro-byt-n2820     total:223  pass:171  dwarn:0   dfail:0   fail:5   skip:47 
ro-hsw-i3-4010u  total:223  pass:188  dwarn:0   dfail:0   fail:2   skip:33 
ro-hsw-i7-4770r  total:223  pass:188  dwarn:0   dfail:0   fail:2   skip:33 
ro-ilk-i7-620lm  total:223  pass:148  dwarn:0   dfail:0   fail:3   skip:72 
ro-ilk1-i5-650   total:218  pass:148  dwarn:0   dfail:0   fail:3   skip:67 
ro-ivb-i7-3770   total:223  pass:179  dwarn:0   dfail:0   fail:2   skip:42 
ro-ivb2-i7-3770  total:223  pass:183  dwarn:0   dfail:0   fail:2   skip:38 
ro-skl3-i5-6260u total:223  pass:199  dwarn:1   dfail:0   fail:2   skip:21 
ro-snb-i7-2620M  total:223  pass:172  dwarn:0   dfail:0   fail:3   skip:48 
ro-bdw-i7-5557U failed to connect after reboot

Results at /archive/results/CI_IGT_test/RO_Patchwork_1242/

9bb3a64 drm-intel-nightly: 2016y-06m-20d-14h-58m-45s UTC integration manifest
ca52fa3 drm: fix send_vblank_event use-after-free error

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 3+ messages in thread
* Re: [PATCH] drm: fix send_vblank_event use-after-free error
  2016-06-20 16:42 [PATCH] drm: fix send_vblank_event use-after-free error Matthew Auld
  2016-06-20 17:17 ` ✗ Ro.CI.BAT: warning for " Patchwork
@ 2016-06-20 19:18 ` Daniel Vetter
  1 sibling, 0 replies; 3+ messages in thread
From: Daniel Vetter @ 2016-06-20 19:18 UTC (permalink / raw)
  To: Matthew Auld; +Cc: Daniel Vetter, intel-gfx, dri-devel

On Mon, Jun 20, 2016 at 05:42:46PM +0100, Matthew Auld wrote:
> The drm_pending_event can be freed by drm_send_event_locked, as a
> result we should call trace_drm_vblank_event_delivered before this
> to avoid hitting a user-after-free error when accessing the pid member:
> 
> [  378.438497] BUG: KASAN: use-after-free in send_vblank_event+0xf0/0x310 [drm] at addr ffff8801ac7e50a0
> [  378.438500] Read of size 4 by task Xorg/1562
> [  378.438501] =============================================================================
> [  378.438504] BUG kmalloc-128 (Tainted: G    B          ): kasan: bad access detected
> [  378.438506] -----------------------------------------------------------------------------
> 
> [  378.438509] INFO: Freed in 0x10001309c age=18446737369265680575 cpu=0 pid=0
> [  378.438541]  drm_send_event_locked+0x207/0x2f0 [drm]
> [  378.438544]  __slab_free+0x24c/0x650
> [  378.438546]  kfree+0x3a2/0x760
> [  378.438578]  drm_send_event_locked+0x207/0x2f0 [drm]
> [  378.438610]  send_vblank_event+0xb7/0x310 [drm]
> [  378.438643]  drm_crtc_send_vblank_event+0x130/0x1f0 [drm]
> [  378.438722]  intel_atomic_commit_tail+0x23b5/0x53f0 [i915]
> [  378.438802]  intel_atomic_commit+0xbae/0x12f0 [i915]
> [  378.438839]  drm_atomic_commit+0xb0/0x120 [drm]
> [  378.438855]  drm_atomic_helper_connector_dpms+0x339/0x5d0 [drm_kms_helper]
> [  378.438891]  drm_mode_obj_set_property_ioctl+0x8f1/0xcc0 [drm]
> [  378.438927]  drm_mode_connector_property_set_ioctl+0xf3/0x170 [drm]
> [  378.438959]  drm_ioctl+0x2d7/0xae0 [drm]
> [  378.438962]  do_vfs_ioctl+0x1c9/0x1280
> [  378.438964]  SyS_ioctl+0x79/0x90
> [  378.438967]  entry_SYSCALL_64_fastpath+0x1a/0xa4
> 
> Cc: dri-devel@lists.freedesktop.org
> Cc: Daniel Vetter <daniel.vetter@intel.com>
> Signed-off-by: Matthew Auld <matthew.auld@intel.com>

Nice catch, applied to drm-misc.

Thanks, Daniel

> ---
>  drivers/gpu/drm/drm_irq.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
> index 76e39c5..8ca3d2b 100644
> --- a/drivers/gpu/drm/drm_irq.c
> +++ b/drivers/gpu/drm/drm_irq.c
> @@ -994,10 +994,10 @@ static void send_vblank_event(struct drm_device *dev,
>  	e->event.tv_sec = now->tv_sec;
>  	e->event.tv_usec = now->tv_usec;
>  
> -	drm_send_event_locked(dev, &e->base);
> -
>  	trace_drm_vblank_event_delivered(e->base.pid, e->pipe,
>  					 e->event.sequence);
> +
> +	drm_send_event_locked(dev, &e->base);
>  }
>  
>  /**
> -- 
> 2.5.5
> 
> _______________________________________________
> Intel-gfx mailing list
> Intel-gfx@lists.freedesktop.org
> https://lists.freedesktop.org/mailman/listinfo/intel-gfx

-- 
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

^ permalink raw reply	[flat|nested] 3+ messages in thread
end of thread, other threads:[~2016-06-20 19:18 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2016-06-20 16:42 [PATCH] drm: fix send_vblank_event use-after-free error Matthew Auld
2016-06-20 17:17 ` ✗ Ro.CI.BAT: warning for " Patchwork
2016-06-20 19:18 ` [PATCH] " Daniel Vetter

This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.