This is a note to let you know that I've just added the patch titled md-cluster: fix potential lock issue in add_new_disk to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: md-cluster-fix-potential-lock-issue-in-add_new_disk.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue Apr 10 10:31:53 CEST 2018 From: Guoqing Jiang <gqjiang@xxxxxxxx> Date: Tue, 16 May 2017 14:01:25 +0800 Subject: md-cluster: fix potential lock issue in add_new_disk From: Guoqing Jiang <gqjiang@xxxxxxxx> [ Upstream commit 2dffdc0724004f38f5e39907747b53e4b0d80e59 ] 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@xxxxxxxxxx> CC: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx> Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx> Signed-off-by: Shaohua Li <shli@xxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/md-cluster.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) --- a/drivers/md/md-cluster.c +++ b/drivers/md/md-cluster.c @@ -945,8 +945,10 @@ static int add_new_disk(struct mddev *md cmsg.raid_slot = cpu_to_le32(rdev->desc_nr); lock_comm(cinfo); 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; Patches currently in stable-queue which might be from gqjiang@xxxxxxxx are queue-4.4/md-cluster-fix-potential-lock-issue-in-add_new_disk.patch