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Subject: Re: [PATCH] fs:Fix kmemleak leak warning in getname_flags about
 working on unitialized memory
To: Al Viro <viro@ZenIV.linux.org.uk>,
        Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
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 <20160804135712.GK2356@ZenIV.linux.org.uk>
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From: Eric Sandeen <sandeen@sandeen.net>
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Date: Thu, 1 Sep 2016 08:10:44 -0500
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On 8/4/16 8:57 AM, Al Viro wrote:

> Don't feed the troll.  On all paths leading to that place we have
>         result->name = kname;
>         len = strncpy_from_user(kname, filename, EMBEDDED_NAME_MAX);
> or
>                 result->name = kname;
>                 len = strncpy_from_user(kname, filename, PATH_MAX);
> with failure exits taken if strncpy_from_user() returns an error, which means
> that the damn thing has already been copied into.
> 
> FWIW, it looks a lot like buggered kmemcheck; as usual, he can't be bothered
> to mention which kernel version would it be (let alone how to reproduce it
> on the kernel in question), but IIRC davej had run into some instrumentation
> breakage lately.

The original report is in https://bugzilla.kernel.org/show_bug.cgi?id=120651
if anyone is interested in it.

-Eric

> Again, don't feed the troll - you are only inviting an "improved" version
> of that garbage, just as pointless.