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: v3.16.35~103
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=31a055ab230e77270be39fb4204f1d244953a3c7;p=thirdparty%2Fkernel%2Fstable.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>
[bwh: Backported to 3.16: add the 'out' label]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---

diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c
index 1a81373947f33..f39ff1c6a041d 100644
--- a/fs/proc_namespace.c
+++ b/fs/proc_namespace.c
@@ -191,6 +191,8 @@ 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 ");
@@ -216,6 +218,7 @@ static int show_vfsstat(struct seq_file *m, struct vfsmount *mnt)
 	}
 
 	seq_putc(m, '\n');
+out:
 	return err;
 }