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Date: Mon, 4 Sep 2017 14:21:07 +0100
From: Al Viro <viro@ZenIV.linux.org.uk>
To: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: linux-fsdevel@vger.kernel.org
Subject: Re: fs: Uninitialized memory read at take_dentry_name_snapshot
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On Mon, Sep 04, 2017 at 09:12:38PM +0900, Tetsuo Handa wrote:
> Hello.
> 
> I hit kmemcheck splat on commit 49d31c2f389acfe8 ("dentry name snapshots") using linux-next-20170901.
> Changing to strncpy() fixes this problem, but using strncpy() only if CONFIG_KMEMCHECK=y is better
> for performance?

*shrug*

If anything, use dentry->d_name.len + 1 instead of DNAME_INLINE_LEN there, but
that's really a false positive.