[PATCH v6 1/2] accel/rocket: Check allocations before use

[Triet Hoang]

Check the result of kmalloc_objs() in rocket_job_open() 
before using the allocated buffers.

Also replace the WARN_ON(ret) check in rocket_job_open() with a plain if
since ret can be -ENOMEM from drm_sched_entity_stats_new(). 
That is an allocation failure, not a driver bug, so a plain if 
seems better than a stack trace.

Fixes: 0810d5ad88a1 ("accel/rocket: Add job submission IOCTL")
Signed-off-by: Triet Hoang <triet.hoang.dev@xxxxxxxxx>
Tested-by: Igor Paunovic <royalnet026@xxxxxxxxx>
Tested-by: Sidong Yang <sidong.yang@xxxxxxxxxx>
---
Changes in v2:
- Free scheds when drm_sched_entity_init() fails.
- Initialize ret to 0.

Changes in v3:
- Move patch version descriptions below the '---' marker.

Changes in v4:
- Remove unnecessary initialization of ret to 0.
- Adjust commit message word wrapping.
- Add Fixes tag.

Changes in v5:
- Add check overflow before kvmalloc_array() in rocket_job_push().

Changes in v6:
- Rebase on top of drm-misc-next, remove the rocket_job_push() hunk.
- Change WARN_ON(ret) to plain if check in rocket_job_open().
- Add Tested-by tags.
---
 drivers/accel/rocket/rocket_job.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/accel/rocket/rocket_job.c b/drivers/accel/rocket/rocket_job.c
index f40435505818..704a15513179 100644
--- a/drivers/accel/rocket/rocket_job.c
+++ b/drivers/accel/rocket/rocket_job.c
@@ -516,6 +516,9 @@ int rocket_job_open(struct rocket_file_priv *rocket_priv)
 	unsigned int core;
 	int ret;
 
+	if (!scheds)
+		return -ENOMEM;
+
 	for (core = 0; core < rdev->num_cores; core++)
 		scheds[core] = &rdev->cores[core].sched;
 
@@ -523,10 +526,10 @@ int rocket_job_open(struct rocket_file_priv *rocket_priv)
 				    DRM_SCHED_PRIORITY_NORMAL,
 				    scheds,
 				    rdev->num_cores, NULL);
-	if (WARN_ON(ret))
-		return ret;
+	if (ret)
+		kfree(scheds);
 
-	return 0;
+	return ret;
 }
 
 void rocket_job_close(struct rocket_file_priv *rocket_priv)
-- 
2.53.0