From: Dmitry V. Levin <ldv@altlinux.org>
Date: Thu, 19 Mar 2015 11:10:54 +0000 (+0000)
Subject: vfs: show_vfsstat: do not ignore errors from show_devname method
X-Git-Tag: firefly_0821_release~176^2~4^2~50^2~75
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=994f9db39113a268394fcba06537cabfbb40cb2b;p=firefly-linux-kernel-4.4.55.git

vfs: show_vfsstat: do not ignore errors from show_devname method

commit 5f8d498d4364f544fee17125787a47553db02afa upstream.

Explicitly check show_devname method return code and bail out in case
of an error.  This fixes regression introduced by commit 9d4d65748a5c.

Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index 8ebd9a334085..87645955990d 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -197,6 +197,8 @@ static int show_vfsstat(struct seq_file *m, struct vfsmount *mnt)
 	if (sb->s_op->show_devname) {
 		seq_puts(m, "device ");
 		err = sb->s_op->show_devname(m, mnt_path.dentry);
+		if (err)
+			goto out;
 	} else {
 		if (r->mnt_devname) {
 			seq_puts(m, "device ");