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Date: Thu, 22 Mar 2012 20:10:27 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Eric Paris <eparis@parisplace.org>
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        linux-kernel@vger.kernel.org, xen-devel@lists.xensource.com
Subject: Re: Regression introduced by
 bfcfaa77bdf0f775263e906015982a608df01c76 (vfs: use 'unsigned long' accesses
 for dcache name comparison and hashing)
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On Thu, Mar 22, 2012 at 04:03:45PM -0400, Eric Paris wrote:
> Reverting this patch also fixed the spurious ENOENT problems (and
> related boot failures) from SELinux.
> 
> Easy reproducer with SELinux enabled (although might I suggest
> permissive/enforcing=0 since the box can't boot otherwise):
> 
> compute_create system_u:system_r:kernel_t:s0
> system_u:object_r:init_exec_t:s0 process
> 
> If you get back system_u:object_r:init_exec_t:s0 it failed and you'll
> see under strace the ENOENT stat() failure.
> 
> If you get back system_u:object_r:init_t:s0 it means it worked...

Unless I'm misreading that code, the problem should hit on names with
length being a multiple of 8...