From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Al Viro , Steven Whitehouse Subject: [PATCH 3.16 296/357] GFS2: fix d_splice_alias() misuses Date: Fri, 3 Oct 2014 14:31:22 -0700 Message-Id: <20141003212942.377284187@linuxfoundation.org> In-Reply-To: <20141003212933.458851516@linuxfoundation.org> References: <20141003212933.458851516@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 3.16-stable review patch. If anyone has any objections, please let me know. ------------------ From: Al Viro commit cfb2f9d5c921e38b0f12bb26fed10b877664444d upstream. Callers of d_splice_alias(dentry, inode) don't need iput(), neither on success nor on failure. Either the reference to inode is stored in a previously negative dentry, or it's dropped. In either case inode reference the caller used to hold is consumed. __gfs2_lookup() does iput() in case when d_splice_alias() has failed. Double iput() if we ever hit that. And gfs2_create_inode() ends up not only with double iput(), but with link count dropped to zero - on an inode it has just found in directory. Signed-off-by: Al Viro Signed-off-by: Steven Whitehouse Signed-off-by: Greg Kroah-Hartman --- fs/gfs2/inode.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/fs/gfs2/inode.c +++ b/fs/gfs2/inode.c @@ -626,8 +626,10 @@ static int gfs2_create_inode(struct inod if (!IS_ERR(inode)) { d = d_splice_alias(inode, dentry); error = PTR_ERR(d); - if (IS_ERR(d)) + if (IS_ERR(d)) { + inode = ERR_CAST(d); goto fail_gunlock; + } error = 0; if (file) { if (S_ISREG(inode->i_mode)) { @@ -854,7 +856,6 @@ static struct dentry *__gfs2_lookup(stru d = d_splice_alias(inode, dentry); if (IS_ERR(d)) { - iput(inode); gfs2_glock_dq_uninit(&gh); return d; }