6.6-stable review patch. If anyone has any objections, please let me know.
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From: Srinivasan Shanmugam srinivasan.shanmugam@amd.com
[ Upstream commit 38e6f715b02b572f74677eb2f29d3b4bc6f1ddff ]
This commit adds a null check for the 'afb' variable in the amdgpu_dm_plane_handle_cursor_update function. Previously, 'afb' was assumed to be null, but was used later in the code without a null check. This could potentially lead to a null pointer dereference.
Fixes the below: drivers/gpu/drm/amd/amdgpu/../display/amdgpu_dm/amdgpu_dm_plane.c:1298 amdgpu_dm_plane_handle_cursor_update() error: we previously assumed 'afb' could be null (see line 1252)
Cc: Tom Chung chiahsuan.chung@amd.com Cc: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Cc: Roman Li roman.li@amd.com Cc: Hersen Wu hersenxs.wu@amd.com Cc: Alex Hung alex.hung@amd.com Cc: Aurabindo Pillai aurabindo.pillai@amd.com Cc: Harry Wentland harry.wentland@amd.com Signed-off-by: Srinivasan Shanmugam srinivasan.shanmugam@amd.com Reviewed-by: Harry Wentland harry.wentland@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c index cc74dd69acf2b..eb77de95f26f5 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_plane.c @@ -1225,14 +1225,22 @@ void amdgpu_dm_plane_handle_cursor_update(struct drm_plane *plane, { struct amdgpu_device *adev = drm_to_adev(plane->dev); struct amdgpu_framebuffer *afb = to_amdgpu_framebuffer(plane->state->fb); - struct drm_crtc *crtc = afb ? plane->state->crtc : old_plane_state->crtc; - struct dm_crtc_state *crtc_state = crtc ? to_dm_crtc_state(crtc->state) : NULL; - struct amdgpu_crtc *amdgpu_crtc = to_amdgpu_crtc(crtc); - uint64_t address = afb ? afb->address : 0; + struct drm_crtc *crtc; + struct dm_crtc_state *crtc_state; + struct amdgpu_crtc *amdgpu_crtc; + u64 address; struct dc_cursor_position position = {0}; struct dc_cursor_attributes attributes; int ret;
+ if (!afb) + return; + + crtc = plane->state->crtc ? plane->state->crtc : old_plane_state->crtc; + crtc_state = crtc ? to_dm_crtc_state(crtc->state) : NULL; + amdgpu_crtc = to_amdgpu_crtc(crtc); + address = afb->address; + if (!plane->state->fb && !old_plane_state->fb) return;