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@xxxxxxx>
Cc: Rodrigo Siqueira <Rodrigo.Siqueira@xxxxxxx>
Cc: Roman Li <roman.li@xxxxxxx>
Cc: Hersen Wu <hersenxs.wu@xxxxxxx>
Cc: Alex Hung <alex.hung@xxxxxxx>
Cc: Aurabindo Pillai <aurabindo.pillai@xxxxxxx>
Cc: Harry Wentland <harry.wentland@xxxxxxx>
Signed-off-by: Srinivasan Shanmugam <srinivasan.shanmugam@xxxxxxx>
---
.../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 a64f20fcddaa..b339642b86c0 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
@@ -1246,14 +1246,22 @@ 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;
--
2.34.1
