From: Zheyu Ma <zheyuma97@gmail.com> stable inclusion from stable-5.10.55 commit 5c3d753b872a706af9317fef4edfb6b640d8a71e bugzilla: 175636 https://gitee.com/openeuler/kernel/issues/I4DYWD Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- [ 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@gmail.com> Reviewed-by: Christian König <christian.koenig@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/1626274459-8148-1-git-send-ema... Signed-off-by: Christian König <christian.koenig@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- drivers/gpu/drm/ttm/ttm_range_manager.c | 3 +++ 1 file changed, 3 insertions(+) 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); -- 2.20.1