Skip site navigation (1)Skip section navigation (2)
Date:      Mon, 23 Jul 2001 20:01:33 -0700
From:      Julian Elischer <julian@elischer.org>
To:        Brooks Davis <brooks@one-eyed-alien.net>
Cc:        net@freebsd.org
Subject:   Re: error in ip_checkinterface code?
Message-ID:  <3B5CE50D.D57F5E72@elischer.org>
References:  <20010723184418.B28097@Odin.AC.HMC.Edu>

next in thread | previous in thread | raw e-mail | index | archive | help
Brooks Davis wrote:
> 
> I just ran into what appears to be a bug in the ip_checkinterface code.
> The problem is that is assumes m->m_pkthdr.rcvif is non-NULL.
> Apparently this is normally true, but I have some netgraph code that
> processes it's processes in such a way that they lose their interface
> pointer which means that when I stick them back into the ip_stack get a
> panic.  A quick patch that fixes the problem is included below.  Is
> this fix correct?
> 
> -- Brooks
> 
> Index: ip_input.c
> ===================================================================
> RCS file: /home/ncvs/src/sys/netinet/ip_input.c,v
> retrieving revision 1.174
> diff -u -r1.174 ip_input.c
> --- ip_input.c  2001/06/23 17:17:58     1.174
> +++ ip_input.c  2001/07/24 01:46:22
> @@ -559,6 +559,7 @@
>          * the packets are received.
>          */
>         checkif = ip_checkinterface && (ipforwarding == 0) &&
> +           m->m_pkthdr.rcvif != NULL &&
>             ((m->m_pkthdr.rcvif->if_flags & IFF_LOOPBACK) == 0) &&
>             (ip_fw_fwd_addr == NULL);

another possibility is to assign an incoming interface to the reinjected packet
:-)

(what are you using netgraph for?)


> 
> --
> Any statement of the form "X is the one, true Y" is FALSE.
> PGP fingerprint 655D 519C 26A7 82E7 2529  9BF0 5D8E 8BE9 F238 1AD4
> 
>   --------------------------------------------------------------------------------
>    Part 1.2Type: application/pgp-signature

-- 
+------------------------------------+       ______ _  __
|   __--_|\  Julian Elischer         |       \     U \/ / hard at work in 
|  /       \ julian@elischer.org     +------>x   USA    \ a very strange
| (   OZ    )                                \___   ___ | country !
+- X_.---._/    presently in San Francisco       \_/   \\
          v

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-net" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?3B5CE50D.D57F5E72>