[PATCH AUTOSEL 5.4 51/57] drm/amdgpu: fix NULL pointer dereference
From: Sasha Levin <sashal@kernel.org>
Date: 2021-05-03 16:57:57
Also in:
amd-gfx, dri-devel, lkml
Subsystem:
drm drivers, radeon and amdgpu drm drivers, the rest · Maintainers:
David Airlie, Simona Vetter, Alex Deucher, Christian König, Linus Torvalds
From: Guchun Chen <redacted> [ Upstream commit 3c3dc654333f6389803cdcaf03912e94173ae510 ] ttm->sg needs to be checked before accessing its child member. Call Trace: amdgpu_ttm_backend_destroy+0x12/0x70 [amdgpu] ttm_bo_cleanup_memtype_use+0x3a/0x60 [ttm] ttm_bo_release+0x17d/0x300 [ttm] amdgpu_bo_unref+0x1a/0x30 [amdgpu] amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu+0x78b/0x8b0 [amdgpu] kfd_ioctl_alloc_memory_of_gpu+0x118/0x220 [amdgpu] kfd_ioctl+0x222/0x400 [amdgpu] ? kfd_dev_is_large_bar+0x90/0x90 [amdgpu] __x64_sys_ioctl+0x8e/0xd0 ? __context_tracking_exit+0x52/0x90 do_syscall_64+0x33/0x80 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f97f264d317 Code: b3 66 90 48 8b 05 71 4b 2d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 41 4b 2d 00 f7 d8 64 89 01 48 RSP: 002b:00007ffdb402c338 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f97f3cc63a0 RCX: 00007f97f264d317 RDX: 00007ffdb402c380 RSI: 00000000c0284b16 RDI: 0000000000000003 RBP: 00007ffdb402c380 R08: 00007ffdb402c428 R09: 00000000c4000004 R10: 00000000c4000004 R11: 0000000000000246 R12: 00000000c0284b16 R13: 0000000000000003 R14: 00007f97f3cc63a0 R15: 00007f8836200000 Signed-off-by: Guchun Chen <redacted> Acked-by: Christian König <christian.koenig@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
index c6a1dfe79e80..91e3a87b1de8 100644
--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c@@ -984,7 +984,7 @@ static void amdgpu_ttm_tt_unpin_userptr(struct ttm_tt *ttm) DMA_BIDIRECTIONAL : DMA_TO_DEVICE; /* double check that we don't free the table twice */ - if (!ttm->sg->sgl) + if (!ttm->sg || !ttm->sg->sgl) return; /* unmap the pages mapped to the device */
--
2.30.2