Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753544AbaG3MSG (ORCPT ); Wed, 30 Jul 2014 08:18:06 -0400 Received: from ip4-83-240-18-248.cust.nbox.cz ([83.240.18.248]:36822 "EHLO ip4-83-240-18-248.cust.nbox.cz" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753057AbaG3MPf (ORCPT ); Wed, 30 Jul 2014 08:15:35 -0400 From: Jiri Slaby To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Vasily Averin , Vasily Averin , Christoph Hellwig , Jiri Slaby Subject: [PATCH 3.12 90/94] fs: umount on symlink leaks mnt count Date: Wed, 30 Jul 2014 14:15:19 +0200 Message-Id: <704a98917dfc367aad4238f69d1853942255ed5d.1406722270.git.jslaby@suse.cz> X-Mailer: git-send-email 2.0.1 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Vasily Averin 3.12-stable review patch. If anyone has any objections, please let me know. =============== commit 295dc39d941dc2ae53d5c170365af4c9d5c16212 upstream. Currently umount on symlink blocks following umount: /vz is separate mount # ls /vz/ -al | grep test drwxr-xr-x. 2 root root 4096 Jul 19 01:14 testdir lrwxrwxrwx. 1 root root 11 Jul 19 01:16 testlink -> /vz/testdir # umount -l /vz/testlink umount: /vz/testlink: not mounted (expected) # lsof /vz # umount /vz umount: /vz: device is busy. (unexpected) In this case mountpoint_last() gets an extra refcount on path->mnt Signed-off-by: Vasily Averin Acked-by: Ian Kent Acked-by: Jeff Layton Signed-off-by: Christoph Hellwig Signed-off-by: Jiri Slaby --- fs/namei.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/namei.c b/fs/namei.c index 338d08b7eae2..e3249d565c95 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -2281,9 +2281,10 @@ done: goto out; } path->dentry = dentry; - path->mnt = mntget(nd->path.mnt); + path->mnt = nd->path.mnt; if (should_follow_link(dentry->d_inode, nd->flags & LOOKUP_FOLLOW)) return 1; + mntget(path->mnt); follow_mount(path); error = 0; out: -- 2.0.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/