block: fix error in handling dead task for ioprio setting

Don't combine the task exiting and "already have io_context" case, we need to just abort if the task is marked as dead. Return -ESRCH, which is the documented value for ioprio_set() if the specified task could not be found. Reported-by: Dan Carpenter <[email protected]> Reported-by: [email protected] Fixes: 5fc11ee ("block: open code create_task_io_context in set_task_ioprio") Signed-off-by: Jens Axboe <[email protected]>
dedewu6 · Dec 21, 2021 · a957b61 · a957b61
1 parent 518579a
commit a957b61
Showing 1 changed file with 8 additions and 2 deletions.
diff --git a/block/blk-ioc.c b/block/blk-ioc.c
@@ -279,16 +279,22 @@ int set_task_ioprio(struct task_struct *task, int ioprio)
 			return -ENOMEM;
 
 		task_lock(task);
-		if (task->io_context || (task->flags & PF_EXITING)) {
+		if (task->flags & PF_EXITING) {
+			err = -ESRCH;
+			kmem_cache_free(iocontext_cachep, ioc);
+			goto out;
+		}
+		if (task->io_context) {
 			kmem_cache_free(iocontext_cachep, ioc);
 			ioc = task->io_context;
 		} else {
 			task->io_context = ioc;
 		}
 	}
 	task->io_context->ioprio = ioprio;
+out:
 	task_unlock(task);
-	return 0;
+	return err;
 }
 EXPORT_SYMBOL_GPL(set_task_ioprio);