This is a note to let you know that I've just added the patch titled drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-radeon-fix-race-condition-uaf-in-radeon_gem_set_.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit d8d79fdc38afbafdd90a7046a0dd04abd3712a71 Author: Min Li <lm0963hack@xxxxxxxxx> Date: Sat Jun 3 15:43:45 2023 +0800 drm/radeon: fix race condition UAF in radeon_gem_set_domain_ioctl [ Upstream commit 982b173a6c6d9472730c3116051977e05d17c8c5 ] Userspace can race to free the gobj(robj converted from), robj should not be accessed again after drm_gem_object_put, otherwith it will result in use-after-free. Reviewed-by: Christian König <christian.koenig@xxxxxxx> Signed-off-by: Min Li <lm0963hack@xxxxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/radeon/radeon_gem.c b/drivers/gpu/drm/radeon/radeon_gem.c index b2b076606f54b..e164b3c7a234f 100644 --- a/drivers/gpu/drm/radeon/radeon_gem.c +++ b/drivers/gpu/drm/radeon/radeon_gem.c @@ -384,7 +384,6 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, struct radeon_device *rdev = dev->dev_private; struct drm_radeon_gem_set_domain *args = data; struct drm_gem_object *gobj; - struct radeon_bo *robj; int r; /* for now if someone requests domain CPU - @@ -397,13 +396,12 @@ int radeon_gem_set_domain_ioctl(struct drm_device *dev, void *data, up_read(&rdev->exclusive_lock); return -ENOENT; } - robj = gem_to_radeon_bo(gobj); r = radeon_gem_set_domain(gobj, args->read_domains, args->write_domain); drm_gem_object_put_unlocked(gobj); up_read(&rdev->exclusive_lock); - r = radeon_gem_handle_lockup(robj->rdev, r); + r = radeon_gem_handle_lockup(rdev, r); return r; }