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Date:   Thu, 16 Mar 2023 12:36:03 +0100
From:   Florian Westphal <fw@strlen.de>
To:     Jeremy Sowden <jeremy@azazel.net>
Cc:     Netfilter Devel <netfilter-devel@vger.kernel.org>
Subject: Re: [PATCH ulogd2 v3 0/2] pcap: prevent crashes when output `FILE *`
 is null
Message-ID: <20230316113603.GK4072@breakpoint.cc>
References: <20230316110754.260967-1-jeremy@azazel.net>
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Jeremy Sowden <jeremy@azazel.net> wrote:
> If ulogd2 receives a signal it will attempt to re-open the pcap output
> file.  If this fails (because the permissions or ownership have changed
> for example), the FILE pointer will be null and when the next packet
> comes in, the null pointer will be passed to fwrite and ulogd will
> crash.
> 
> The first patch simplifies the logic of the code that opens the output
> file, and the second avoids closing the existing stream if `fopen`
> fails.
> 
> Link: https://bugs.launchpad.net/ubuntu/+source/ulogd2/+bug/1429778
> 
> Change since v2
> 
>  * The first patch is new.
>  * In the second patch, just keep the old stream open, rather than
>    disabling output and trying to reopen at intervals.

LGTM, thanks Jeremy.