From d31da0f0ba3bc0a827a63879310818c22d9a95be Mon Sep 17 00:00:00 2001
From: Al Viro <viro@zeniv.linux.org.uk>
Date: Tue, 22 Nov 2011 12:31:21 -0500
Subject: [PATCH] mount_subtree() pointless use-after-free

d'oh... we'd carefully pinned mnt->mnt_sb down, dropped mnt and attempt
to grab s_umount on mnt->mnt_sb.  The trouble is, *mnt might've been
overwritten by now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
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Reading git-format-patch failed