From: Guoqing Jiang <gqjiang@suse.com>
Date: Tue, 16 May 2017 06:01:25 +0000 (+0800)
Subject: md-cluster: fix potential lock issue in add_new_disk
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=2dffdc0724004f38f5e39907747b53e4b0d80e59;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

md-cluster: fix potential lock issue in add_new_disk

The add_new_disk returns with communication locked if
__sendmsg returns failure, fix it with call unlock_comm
before return.

Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
CC: Goldwyn Rodrigues <rgoldwyn@suse.com>
Signed-off-by: Guoqing Jiang <gqjiang@suse.com>
Signed-off-by: Shaohua Li <shli@fb.com>
---

diff --git a/drivers/md/md-cluster.c b/drivers/md/md-cluster.c
index 7299ce2f08a8..03082e17c65c 100644
--- a/drivers/md/md-cluster.c
+++ b/drivers/md/md-cluster.c
@@ -1311,8 +1311,10 @@ static int add_new_disk(struct mddev *mddev, struct md_rdev *rdev)
 	cmsg.raid_slot = cpu_to_le32(rdev->desc_nr);
 	lock_comm(cinfo, 1);
 	ret = __sendmsg(cinfo, &cmsg);
-	if (ret)
+	if (ret) {
+		unlock_comm(cinfo);
 		return ret;
+	}
 	cinfo->no_new_dev_lockres->flags |= DLM_LKF_NOQUEUE;
 	ret = dlm_lock_sync(cinfo->no_new_dev_lockres, DLM_LOCK_EX);
 	cinfo->no_new_dev_lockres->flags &= ~DLM_LKF_NOQUEUE;