]> git.hungrycats.org Git - linux/commit
drm/xe/guc_submit: add missing locking in wedged_fini
authorMatthew Auld <matthew.auld@intel.com>
Tue, 24 Sep 2024 15:09:48 +0000 (16:09 +0100)
committerMatthew Auld <matthew.auld@intel.com>
Thu, 26 Sep 2024 13:28:06 +0000 (14:28 +0100)
commitd28af0b6b9580b9f90c265a7da0315b0ad20bbfd
tree09148a50c4f87014cddd13c7bddec11d3010b60a
parentfe4f5d4b661666a45b48fe7f95443f8fefc09c8c
drm/xe/guc_submit: add missing locking in wedged_fini

Any non-wedged queue can have a zero refcount here and can be running
concurrently with an async queue destroy, therefore dereferencing the
queue ptr to check wedge status after the lookup can trigger UAF if
queue is not wedged.  Fix this by keeping the submission_state lock held
around the check to postpone the free and make the check safe, before
dropping again around the put() to avoid the deadlock.

Fixes: 8ed9aaae39f3 ("drm/xe: Force wedged state and block GT reset upon any GPU hang")
Signed-off-by: Matthew Auld <matthew.auld@intel.com>
Cc: Matthew Brost <matthew.brost@intel.com>
Reviewed-by: Matthew Brost <matthew.brost@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240924150947.118433-2-matthew.auld@intel.com
drivers/gpu/drm/xe/xe_guc_submit.c