This is a note to let you know that I've just added the patch titled
drm/ttm: add a check against null pointer dereference
to the 5.10-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-ttm-add-a-check-against-null-pointer-dereference.patch
and it can be found in the queue-5.10 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit ed62c2db438b73fcfa1ca325f1cd7d69be9a6f88
Author: Zheyu Ma <zheyuma97@xxxxxxxxx>
Date: Wed Jul 14 14:54:19 2021 +0000
drm/ttm: add a check against null pointer dereference
[ Upstream commit 9e5c772954406829e928dbe59891d08938ead04b ]
When calling ttm_range_man_fini(), 'man' may be uninitialized, which may
cause a null pointer dereference bug.
Fix this by checking if it is a null pointer.
This log reveals it:
[ 7.902580 ] BUG: kernel NULL pointer dereference, address: 0000000000000058
[ 7.905721 ] RIP: 0010:ttm_range_man_fini+0x40/0x160
[ 7.911826 ] Call Trace:
[ 7.911826 ] radeon_ttm_fini+0x167/0x210
[ 7.911826 ] radeon_bo_fini+0x15/0x40
[ 7.913767 ] rs400_fini+0x55/0x80
[ 7.914358 ] radeon_device_fini+0x3c/0x140
[ 7.914358 ] radeon_driver_unload_kms+0x5c/0xe0
[ 7.914358 ] radeon_driver_load_kms+0x13a/0x200
[ 7.914358 ] ? radeon_driver_unload_kms+0xe0/0xe0
[ 7.914358 ] drm_dev_register+0x1db/0x290
[ 7.914358 ] radeon_pci_probe+0x16a/0x230
[ 7.914358 ] local_pci_probe+0x4a/0xb0
Signed-off-by: Zheyu Ma <zheyuma97@xxxxxxxxx>
Reviewed-by: Christian König <christian.koenig@xxxxxxx>
Link: https://patchwork.freedesktop.org/patch/msgid/1626274459-8148-1-git-send-email-zheyuma97@xxxxxxxxx
Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/gpu/drm/ttm/ttm_range_manager.c b/drivers/gpu/drm/ttm/ttm_range_manager.c
index 1da0e277c511..ce9d127edbb5 100644
--- a/drivers/gpu/drm/ttm/ttm_range_manager.c
+++ b/drivers/gpu/drm/ttm/ttm_range_manager.c
@@ -147,6 +147,9 @@ int ttm_range_man_fini(struct ttm_bo_device *bdev,
struct drm_mm *mm = &rman->mm;
int ret;
+ if (!man)
+ return 0;
+
ttm_resource_manager_set_used(man, false);
ret = ttm_resource_manager_force_list_clean(bdev, man);
