[PATCH 5.15 261/917] drm/msm: prevent NULL dereference in msm_gpu_crashstate_capture()

[Greg Kroah-Hartman]

From: Tim Gardner <tim.gardner@xxxxxxxxxxxxx>

[ Upstream commit b220c154832c5cd0df34cbcbcc19d7135c16e823 ]

Coverity complains of a possible NULL dereference:

CID 120718 (#1 of 1): Dereference null return value (NULL_RETURNS)
23. dereference: Dereferencing a pointer that might be NULL state->bos when
    calling msm_gpu_crashstate_get_bo. [show details]
301                        msm_gpu_crashstate_get_bo(state, submit->bos[i].obj,
302                                submit->bos[i].iova, submit->bos[i].flags);

Fix this by employing the same state->bos NULL check as is used in the next
for loop.

Cc: Rob Clark <robdclark@xxxxxxxxx>
Cc: Sean Paul <sean@xxxxxxxxxx>
Cc: David Airlie <airlied@xxxxxxxx>
Cc: Daniel Vetter <daniel@xxxxxxxx>
Cc: linux-arm-msm@xxxxxxxxxxxxxxx
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: freedreno@xxxxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Tim Gardner <tim.gardner@xxxxxxxxxxxxx>
Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20210929162554.14295-1-tim.gardner@xxxxxxxxxxxxx
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
Signed-off-by: Rob Clark <robdclark@xxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/gpu/drm/msm/msm_gpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/msm/msm_gpu.c b/drivers/gpu/drm/msm/msm_gpu.c
index 8a3a592da3a4d..2c46cd968ac4c 100644
--- a/drivers/gpu/drm/msm/msm_gpu.c
+++ b/drivers/gpu/drm/msm/msm_gpu.c
@@ -296,7 +296,7 @@ static void msm_gpu_crashstate_capture(struct msm_gpu *gpu,
 		state->bos = kcalloc(nr,
 			sizeof(struct msm_gpu_state_bo), GFP_KERNEL);
 
-		for (i = 0; i < submit->nr_bos; i++) {
+		for (i = 0; state->bos && i < submit->nr_bos; i++) {
 			if (should_dump(submit, i)) {
 				msm_gpu_crashstate_get_bo(state, submit->bos[i].obj,
 					submit->bos[i].iova, submit->bos[i].flags);
-- 
2.33.0