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From: David Miller <davem@davemloft.net>
To: nelhage@ksplice.com
Cc: robert.olsson@its.uu.se, linux-kernel@vger.kernel.org,
	netdev@vger.kernel.org, eugene@redhat.com
Subject: Re: [PATCH] pktgen: Remove a dangerous debug print.
Date: Wed, 27 Oct 2010 12:21:43 -0700 (PDT)	[thread overview]
Message-ID: <20101027.122143.02260950.davem@davemloft.net> (raw)
In-Reply-To: <1288206788-21063-1-git-send-email-nelhage@ksplice.com>

From: Nelson Elhage <nelhage@ksplice.com>
Date: Wed, 27 Oct 2010 15:13:08 -0400

> We were allocating an arbitrarily-large buffer on the stack, which would allow a
> buggy or malicious userspace program to overflow the kernel stack.
> 
> Since the debug printk() was just printing exactly the text passed from
> userspace, it's probably just as easy for anyone who might use it to augment (or
> just strace(1)) the program writing to the pktgen file, so let's just not bother
> trying to print the whole buffer.
> 
> Signed-off-by: Nelson Elhage <nelhage@ksplice.com>

Only root can write to the pktgen control file.

Also, the debug feature really is used by people's pktgen scripts, you
can't just turn it off.

  reply	other threads:[~2010-10-27 19:21 UTC|newest]

Thread overview: 20+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-10-27 19:13 [PATCH] pktgen: Remove a dangerous debug print Nelson Elhage
2010-10-27 19:21 ` David Miller [this message]
2010-10-27 19:28   ` Nelson Elhage
2010-10-27 19:30     ` David Miller
2010-10-27 19:41     ` Eric Dumazet
2010-10-27 19:49       ` Nelson Elhage
2010-10-27 20:38 ` Ben Greear
2010-10-27 22:12 ` [patch] fix stack overflow in pktgen_if_write() Dan Carpenter
2010-10-27 22:40   ` Dan Carpenter
2010-10-27 22:43   ` [patch v2] " Dan Carpenter
2010-10-27 23:06     ` Nelson Elhage
2010-10-28  6:05       ` Dan Carpenter
2010-10-28  6:05       ` [patch v3] " Dan Carpenter
2010-10-28 15:22         ` Nelson Elhage
2010-10-28 16:28           ` Dan Carpenter
2010-10-28 16:30             ` Nelson Elhage
2010-10-28 23:11         ` Andi Kleen
2010-11-01  3:47           ` Dan Carpenter
2010-10-28 15:20 ` [PATCH] pktgen: Limit how much data we copy onto the stack Nelson Elhage
2010-10-28 18:32   ` David Miller

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