From: dmorris <dmorris@metavize.com>
To: Harald Welte <laforge@netfilter.org>
Cc: netfilter-devel@lists.netfilter.org
Subject: Re: [PATCH] ipt_do_table accesss pskb after it has been freed
Date: Fri, 07 Nov 2003 08:09:35 -0800 [thread overview]
Message-ID: <3FABC3BF.7070808@metavize.com> (raw)
In-Reply-To: <20031107085752.GH5741@sunbeam.de.gnumonks.org>
Harald Welte wrote:
>>I had a target in the mangle/PREROUTING that was freeing the skb and
>>returning NF_STOLEN.
>>ipt_do_table would then cause a kernel panic as it accesses the skb
>>after its freed.
>>
>>Is this a bug? If so, here's the patch.
>>
>>
>
>no, it's not a bug. you should return NF_DROP if you want to have the
>skb dropped.
>
What am I supposed to do if there is no skb to be dropped.
My hook calls some other functions in the kernel which call
skb_free if all is not well.
That leaves me with two choices, either make a copy of the skb,
which i cant do for performance reasons, or apply this patch.
Do I have other options?
Does the netfilter code assume that skb_free cannot be called from
within hooks?
and do you see any unintended consequences of this hack?
-dirk
next prev parent reply other threads:[~2003-11-07 16:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2003-11-07 2:18 [PATCH] ipt_do_table accesss pskb after it has been freed Dirk Morris
2003-11-07 8:57 ` Harald Welte
2003-11-07 16:09 ` dmorris [this message]
2003-11-07 18:18 ` Henrik Nordstrom
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