From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro@ZenIV.linux.org.uk>
Subject: Re: [PATCH] mnt: Fix a memory stomp in umount
Date: Fri, 2 Jan 2015 21:13:03 +0000
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Cc: Linus Torvalds <torvalds@linux-foundation.org>,
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To: "Eric W. Biederman" <ebiederm@xmission.com>
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On Fri, Jan 02, 2015 at 03:06:06PM -0600, Eric W. Biederman wrote:

> - It requires keeping track of the tail of the list which is half of the
>   error prone complexity.

Er...  In umount_tree() it comes pretty much for free, actually.

> - I have a fix for a bad interaction between MNT_LOCKED and MNT_DETACH
>   where I need to leave mounts on the mount hash, until the final
>   mntput.  For that I need not to reuse the the mnt_hash lists.

Details, please.