[PATCH] blk-mq: Fix refcounting leak in __blk_mq_register_dev()

From: Dan Carpenter
Date: Sat Sep 05 2020 - 08:52:24 EST


There is a kobject_add() hidden in the call to kobject_add().

ret = kobject_add(q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
^^^^^^^^^^^^^^^^^^^^^^^

It needs to be release on the error path.

Fixes: 320ae51feed5 ("blk-mq: new multi-queue block IO queueing mechanism")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
---
block/blk-mq-sysfs.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/block/blk-mq-sysfs.c b/block/blk-mq-sysfs.c
index 062229395a50..5a63659163c1 100644
--- a/block/blk-mq-sysfs.c
+++ b/block/blk-mq-sysfs.c
@@ -321,7 +321,7 @@ int __blk_mq_register_dev(struct device *dev, struct request_queue *q)

ret = kobject_add(q->mq_kobj, kobject_get(&dev->kobj), "%s", "mq");
if (ret < 0)
- goto out;
+ goto out_kobj;

kobject_uevent(q->mq_kobj, KOBJ_ADD);

@@ -333,8 +333,7 @@ int __blk_mq_register_dev(struct device *dev, struct request_queue *q)

q->mq_sysfs_init_done = true;

-out:
- return ret;
+ return 0;

unreg:
while (--i >= 0)
@@ -342,6 +341,7 @@ int __blk_mq_register_dev(struct device *dev, struct request_queue *q)

kobject_uevent(q->mq_kobj, KOBJ_REMOVE);
kobject_del(q->mq_kobj);
+out_kobj:
kobject_put(&dev->kobj);
return ret;
}
--
2.28.0