From mboxrd@z Thu Jan  1 00:00:00 1970
From: Al Viro <viro-3bDd1+5oDREiFSDQTTA3OLVCufUGDwFn@public.gmane.org>
Subject: Re: [REVIEW][PATCH 1/3] vfs: In d_path don't call d_dname on a mount
	point
Date: Sun, 1 Dec 2013 05:09:30 +0000
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Cc: Aditya Kali <adityakali-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, "Eric W. Biederman" <ebiederm-aS9lmoZGLiVWk0Htik3J/w@public.gmane.org>, Neil Brown <neilb-l3A5Bk7waGM@public.gmane.org>, Containers <containers-cunTk1MwBs9QetFLy7KEm3xJsTq8ys+cHZ5vskTnxNA@public.gmane.org>, Oleg Nesterov <oleg-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org>, Andy Lutomirski <luto-kltTT9wpgjJwATOyAt5JVQ@public.gmane.org>, Eric Dumazet <edumazet-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org>, linux-fsdevel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Linus Torvalds <torvalds-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org>
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On Sat, Nov 30, 2013 at 05:02:26PM +0000, Al Viro wrote:

> FWIW, the other callers of prepend_path() boil down to /proc/mountinfo
> handling, apparmour d_namespace_path() (separate handling of MNT_INTERNAL,
> __d_path() or d_absolute_path() for the rest) and tomoyo_get_absolute_path()
> (this one directly calls ->d_dname() itself).

While we are at it, what's the origin of if (buflen >= 256) checks in
tomoyo_get_absolute_path() and tomoyo_get_dentry_path()?  The minimal
buflen value they can be called with is PAGE_SIZE - 1.  And if there is
a port with pages two times smaller than VAX ones, they'd better audit
the tree for places assuming that PAGE_SIZE is at least 4K...