From: Chris Bainbridge <chris.bainbridge@gmail.com> stable inclusion from stable-v6.6.88 commit 31e94c7989572f96926673614a3b958915a13ca9 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IC5BNN CVE: CVE-2025-37765 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 8ec0fbb28d049273bfd4f1e7a5ae4c74884beed3 upstream. Fix an oops in ttm_bo_delayed_delete which results from dererencing a dangling pointer: Oops: general protection fault, probably for non-canonical address 0x6b6b6b6b6b6b6b7b: 0000 [#1] PREEMPT SMP CPU: 4 UID: 0 PID: 1082 Comm: kworker/u65:2 Not tainted 6.14.0-rc4-00267-g505460b44513-dirty #216 Hardware name: LENOVO 82N6/LNVNB161216, BIOS GKCN65WW 01/16/2024 Workqueue: ttm ttm_bo_delayed_delete [ttm] RIP: 0010:dma_resv_iter_first_unlocked+0x55/0x290 Code: 31 f6 48 c7 c7 00 2b fa aa e8 97 bd 52 ff e8 a2 c1 53 00 5a 85 c0 74 48 e9 88 01 00 00 4c 89 63 20 4d 85 e4 0f 84 30 01 00 00 <41> 8b 44 24 10 c6 43 2c 01 48 89 df 89 43 28 e8 97 fd ff ff 4c 8b RSP: 0018:ffffbf9383473d60 EFLAGS: 00010202 RAX: 0000000000000001 RBX: ffffbf9383473d88 RCX: 0000000000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffbf9383473d78 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 6b6b6b6b6b6b6b6b R13: ffffa003bbf78580 R14: ffffa003a6728040 R15: 00000000000383cc FS: 0000000000000000(0000) GS:ffffa00991c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000758348024dd0 CR3: 000000012c259000 CR4: 0000000000f50ef0 PKRU: 55555554 Call Trace: <TASK> ? __die_body.cold+0x19/0x26 ? die_addr+0x3d/0x70 ? exc_general_protection+0x159/0x460 ? asm_exc_general_protection+0x27/0x30 ? dma_resv_iter_first_unlocked+0x55/0x290 dma_resv_wait_timeout+0x56/0x100 ttm_bo_delayed_delete+0x69/0xb0 [ttm] process_one_work+0x217/0x5c0 worker_thread+0x1c8/0x3d0 ? apply_wqattrs_cleanup.part.0+0xc0/0xc0 kthread+0x10b/0x240 ? kthreads_online_cpu+0x140/0x140 ret_from_fork+0x40/0x70 ? kthreads_online_cpu+0x140/0x140 ret_from_fork_asm+0x11/0x20 </TASK> The cause of this is: - drm_prime_gem_destroy calls dma_buf_put(dma_buf) which releases the reference to the shared dma_buf. The reference count is 0, so the dma_buf is destroyed, which in turn decrements the corresponding amdgpu_bo reference count to 0, and the amdgpu_bo is destroyed - calling drm_gem_object_release then dma_resv_fini (which destroys the reservation object), then finally freeing the amdgpu_bo. - nouveau_bo obj->bo.base.resv is now a dangling pointer to the memory formerly allocated to the amdgpu_bo. - nouveau_gem_object_del calls ttm_bo_put(&nvbo->bo) which calls ttm_bo_release, which schedules ttm_bo_delayed_delete. - ttm_bo_delayed_delete runs and dereferences the dangling resv pointer, resulting in a general protection fault. Fix this by moving the drm_prime_gem_destroy call from nouveau_gem_object_del to nouveau_bo_del_ttm. This ensures that it will be run after ttm_bo_delayed_delete. Signed-off-by: Chris Bainbridge <chris.bainbridge@gmail.com> Suggested-by: Christian König <christian.koenig@amd.com> Fixes: 22b33e8ed0e3 ("nouveau: add PRIME support") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3937 Cc: Stable@vger.kernel.org Signed-off-by: Danilo Krummrich <dakr@kernel.org> Link: https://patchwork.freedesktop.org/patch/msgid/Z-P4epVK8k7tFZ7C@debian.local Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Liu Kai <liukai284@huawei.com> --- drivers/gpu/drm/nouveau/nouveau_bo.c | 3 +++ drivers/gpu/drm/nouveau/nouveau_gem.c | 3 --- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/gpu/drm/nouveau/nouveau_bo.c b/drivers/gpu/drm/nouveau/nouveau_bo.c index 5d398a422459e..036ee03439728 100644 --- a/drivers/gpu/drm/nouveau/nouveau_bo.c +++ b/drivers/gpu/drm/nouveau/nouveau_bo.c @@ -144,6 +144,9 @@ nouveau_bo_del_ttm(struct ttm_buffer_object *bo) nouveau_bo_del_io_reserve_lru(bo); nv10_bo_put_tile_region(dev, nvbo->tile, NULL); + if (bo->base.import_attach) + drm_prime_gem_destroy(&bo->base, bo->sg); + /* * If nouveau_bo_new() allocated this buffer, the GEM object was never * initialized, so don't attempt to release it. diff --git a/drivers/gpu/drm/nouveau/nouveau_gem.c b/drivers/gpu/drm/nouveau/nouveau_gem.c index 7b69e6df57486..cd97df6903352 100644 --- a/drivers/gpu/drm/nouveau/nouveau_gem.c +++ b/drivers/gpu/drm/nouveau/nouveau_gem.c @@ -87,9 +87,6 @@ nouveau_gem_object_del(struct drm_gem_object *gem) return; } - if (gem->import_attach) - drm_prime_gem_destroy(gem, nvbo->bo.sg); - ttm_bo_put(&nvbo->bo); pm_runtime_mark_last_busy(dev); -- 2.34.1