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Date: Sat, 6 Mar 2010 18:32:54 +0000
From: Al Viro <viro@ZenIV.linux.org.uk>
To: walt <w41ter@gmail.com>
Cc: linux-kernel@vger.kernel.org
Subject: Re: "Switch !O_CREAT case to use of do_last()" causes segfault in
 glibc
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On Sat, Mar 06, 2010 at 10:20:41AM -0800, walt wrote:
> On 03/06/2010 10:03 AM, Al Viro wrote:
> 
> >_Really_ interesting; it doesn't look like an oops - smells like an attempt
> >to do opendir() that fails for some reason, goes unnoticed and resulting
> >FILE * (i.e. NULL) is fed to readdir()?
> >
> >What does it attempt to open?
> 
> Ah, this may help:
> 
> open("/usr/share/zoneinfo/", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 47
> open("/usr/share/zoneinfo/MST7MDT", O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC) = 48

Now that is interesting.  Looks like it has managed to lose O_DIRECTORY check
in the open without trailing slash and (properly) barfed with / added.