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From: daw@cs.berkeley.edu (David Wagner)
To: linux-kernel@vger.kernel.org
Subject: Re: [PATCH 3/4] security/selinux: decrement sizeof size in strncmp
Date: Thu, 12 Nov 2009 18:28:03 +0000 (UTC)	[thread overview]
Message-ID: <hdhk3j$9hl$1@taverner.cs.berkeley.edu> (raw)
In-Reply-To: 4AFC3620.2020809@schaufler-ca.com

Casey Schaufler  wrote:
> I strongly suggest that this is not what is wanted.
>     strcmp(x,y)
> and
>     strncmp(x,y,sizeof(y))
>
> are functionally equivalent and strcmp has a bad reputation in
> the security community because it is associated with potential
> buffer overrun issues.

It does?  Hmm, I don't recall hearing of this bad reputation for strcmp().
Is there a justification for why such a reputation would be deserved?
We're not talking strcpy() here.  strcmp() is fine as long as its
arguments are properly '\0'-terminated; given that, it doesn't introduce
any new buffer overrun risks.

  reply	other threads:[~2009-11-12 18:27 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-11-12  7:49 [PATCH 3/4] security/selinux: decrement sizeof size in strncmp Julia Lawall
2009-11-12  8:16 ` James Morris
2009-11-12 14:53   ` Serge E. Hallyn
2009-11-12 14:57     ` Julia Lawall
2009-11-12 16:21       ` Casey Schaufler
2009-11-12 18:28         ` David Wagner [this message]
2009-11-12 21:41         ` James Morris
2009-11-12 21:59           ` Julia Lawall
2009-11-12 23:56             ` David Wagner
2009-11-13  2:11           ` Casey Schaufler
2009-11-13 20:32             ` David Wagner
2009-11-13 21:23             ` Valdis.Kletnieks
2009-11-13 21:26               ` Julia Lawall
2009-11-13 23:08                 ` Valdis.Kletnieks
2009-11-14  0:41                   ` David Wagner
2009-11-14  5:08                     ` Valdis.Kletnieks
2009-11-14 15:22                   ` Julia Lawall
2009-11-13 23:06               ` David Wagner
2009-11-14  3:06               ` Casey Schaufler
2009-11-14  3:44                 ` David Wagner
2009-11-14  3:48                   ` Joe Perches
2009-11-14  5:12                     ` Casey Schaufler
2009-11-14  5:26                       ` Joe Perches
2009-11-14  7:20                         ` Casey Schaufler
2009-11-15  7:45                           ` Raja R Harinath
2009-11-15 18:44                             ` Casey Schaufler

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