All of lore.kernel.org
 help / color / mirror / Atom feed
* [PATCH 1/1] drm/xe: Fix error cleanup in xe_exec_queue_create_ioctl()
@ 2026-04-08  2:06 Shuicheng Lin
  2026-04-08  2:17 ` ✗ CI.checkpatch: warning for series starting with [1/1] " Patchwork
                   ` (6 more replies)
  0 siblings, 7 replies; 9+ messages in thread
From: Shuicheng Lin @ 2026-04-08  2:06 UTC (permalink / raw)
  To: intel-xe
  Cc: Shuicheng Lin, Francois Dugast, Matthew Brost,
	Niranjana Vishwanathapura

Two error handling issues exist in xe_exec_queue_create_ioctl():

1. When xe_hw_engine_group_add_exec_queue() fails, the error path jumps
   to put_exec_queue which skips xe_exec_queue_kill(). If the VM is in
   preempt fence mode, xe_vm_add_compute_exec_queue() has already added
   the queue to the VM's compute exec queue list. Skipping the kill
   leaves the queue on that list, leading to a dangling pointer after
   the queue is freed.

2. When xa_alloc() fails after xe_hw_engine_group_add_exec_queue() has
   succeeded, the error path does not call
   xe_hw_engine_group_del_exec_queue() to remove the queue from the hw
   engine group list. The queue is then freed while still linked into
   the hw engine group, causing a use-after-free.

Fix both by:
- Changing the xe_hw_engine_group_add_exec_queue() failure path to jump
  to kill_exec_queue so that xe_exec_queue_kill() properly removes the
  queue from the VM's compute list.
- Adding a del_hw_engine_group label before kill_exec_queue for the
  xa_alloc() failure path, which removes the queue from the hw engine
  group before proceeding with the rest of the cleanup.

Fixes: 7970cb36966c ("'drm/xe/hw_engine_group: Register hw engine group's exec queues")
Cc: Francois Dugast <francois.dugast@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Cc: Niranjana Vishwanathapura <niranjana.vishwanathapura@intel.com>
Assisted-by: Claude:claude-opus-4.6
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
---
This is a reimplementation of https://patchwork.freedesktop.org/series/162714/
Same logic, with improved labeling and a corrected Fixes tag.
---
 drivers/gpu/drm/xe/xe_exec_queue.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_exec_queue.c b/drivers/gpu/drm/xe/xe_exec_queue.c
index b287d0e0e60a..4603ff08d860 100644
--- a/drivers/gpu/drm/xe/xe_exec_queue.c
+++ b/drivers/gpu/drm/xe/xe_exec_queue.c
@@ -1405,7 +1405,7 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
 		if (q->vm && q->hwe->hw_engine_group) {
 			err = xe_hw_engine_group_add_exec_queue(q->hwe->hw_engine_group, q);
 			if (err)
-				goto put_exec_queue;
+				goto kill_exec_queue;
 		}
 	}
 
@@ -1416,12 +1416,15 @@ int xe_exec_queue_create_ioctl(struct drm_device *dev, void *data,
 	/* user id alloc must always be last in ioctl to prevent UAF */
 	err = xa_alloc(&xef->exec_queue.xa, &id, q, xa_limit_32b, GFP_KERNEL);
 	if (err)
-		goto kill_exec_queue;
+		goto del_hw_engine_group;
 
 	args->exec_queue_id = id;
 
 	return 0;
 
+del_hw_engine_group:
+	if (q->vm && q->hwe && q->hwe->hw_engine_group)
+		xe_hw_engine_group_del_exec_queue(q->hwe->hw_engine_group, q);
 kill_exec_queue:
 	xe_exec_queue_kill(q);
 delete_queue_group:
-- 
2.43.0


^ permalink raw reply related	[flat|nested] 9+ messages in thread
end of thread, other threads:[~2026-04-14 15:47 UTC | newest]

Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2026-04-08  2:06 [PATCH 1/1] drm/xe: Fix error cleanup in xe_exec_queue_create_ioctl() Shuicheng Lin
2026-04-08  2:17 ` ✗ CI.checkpatch: warning for series starting with [1/1] " Patchwork
2026-04-08  2:18 ` ✗ CI.KUnit: failure " Patchwork
2026-04-08  4:48 ` [PATCH 1/1] " Matthew Brost
2026-04-10  3:18 ` ✗ CI.checkpatch: warning for series starting with [1/1] drm/xe: Fix error cleanup in xe_exec_queue_create_ioctl() (rev2) Patchwork
2026-04-10  3:19 ` ✓ CI.KUnit: success " Patchwork
2026-04-10  4:10 ` ✓ Xe.CI.BAT: " Patchwork
2026-04-10  9:13 ` ✗ Xe.CI.FULL: failure " Patchwork
2026-04-14 15:47   ` Lin, Shuicheng

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.