On 8/27/24 9:45 AM, Philipp Stanner wrote:
In drm_sched_job_init(), commit 56e449603f0a ("drm/sched: Convert the
GPU scheduler to variable number of run-queues") implemented a call to
drm_err(), which uses the job's scheduler pointer as a parameter.
job->sched, however, is not yet valid as it gets set by
drm_sched_job_arm(), which is always called after drm_sched_job_init().
Since the scheduler code has no control over how the API-User has
allocated or set 'job', the pointer's dereference is undefined behavior.
Fix the UB by replacing drm_err() with pr_err().
Cc: <stable@xxxxxxxxxxxxxxx> # 6.7+
Fixes: 56e449603f0a ("drm/sched: Convert the GPU scheduler to variable number of run-queues")
Reported-by: Danilo Krummrich <dakr@xxxxxxxxxx>
Closes: https://lore.kernel.org/lkml/20231108022716.15250-1-dakr@xxxxxxxxxx/
Signed-off-by: Philipp Stanner <pstanner@xxxxxxxxxx>
---
drivers/gpu/drm/scheduler/sched_main.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
index 7e90c9f95611..356c30fa24a8 100644
--- a/drivers/gpu/drm/scheduler/sched_main.c
+++ b/drivers/gpu/drm/scheduler/sched_main.c
@@ -797,7 +797,7 @@ int drm_sched_job_init(struct drm_sched_job *job,
* or worse--a blank screen--leave a trail in the
* logs, so this can be debugged easier.
*/
- drm_err(job->sched, "%s: entity has no rq!\n", __func__);
+ pr_err("*ERROR* %s: entity has no rq!\n", __func__);
I don't think the "*ERROR*" string is necessary, it's pr_err() already.
Otherwise,
Acked-by: Danilo Krummrich <dakr@xxxxxxxxxx>
return -ENOENT;
}
