5.10-stable review patch. If anyone has any objections, please let me know.
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From: Igor Artemiev Igor.A.Artemiev@mcst.ru
commit 52f1783ff4146344342422c1cd94fcb4ce39b6fe upstream.
The adev->dm.dc pointer can be NULL and dereferenced in amdgpu_dm_fini() without checking.
Add a NULL pointer check before calling dc_dmub_srv_destroy().
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Fixes: 9a71c7d31734 ("drm/amd/display: Register DMUB service with DC") Signed-off-by: Igor Artemiev Igor.A.Artemiev@mcst.ru Signed-off-by: Hamza Mahfooz hamza.mahfooz@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Eslam Khafagy eslam.medhat1993@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -1142,7 +1142,8 @@ static void amdgpu_dm_fini(struct amdgpu dc_deinit_callbacks(adev->dm.dc); #endif
- dc_dmub_srv_destroy(&adev->dm.dc->ctx->dmub_srv); + if (adev->dm.dc) + dc_dmub_srv_destroy(&adev->dm.dc->ctx->dmub_srv);
if (adev->dm.dmub_bo) amdgpu_bo_free_kernel(&adev->dm.dmub_bo,