lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Thu, 6 Feb 2014 06:30:41 -0800 (PST) From: François-Xavier Le Bail <fx.lebail@...oo.com> To: "nicolas.dichtel@...nd.com" <nicolas.dichtel@...nd.com>, "netdev@...r.kernel.org" <netdev@...r.kernel.org> Cc: David Stevens <dlstevens@...ibm.com>, Bill Fink <billfink@...dspring.com>, Hannes Frederic Sowa <hannes@...essinduktion.org>, "David S. Miller" <davem@...emloft.net>, Alexey Kuznetsov <kuznet@....inr.ac.ru>, James Morris <jmorris@...ei.org>, Hideaki Yoshifuji <yoshfuji@...ux-ipv6.org>, Patrick McHardy <kaber@...sh.net> Subject: Re: [PATCH net-next v2] ipv6: enable anycast addresses as source addresses in ICMPv6 error messages > From: Nicolas Dichtel <nicolas.dichtel@...nd.com> > To: François-Xavier Le Bail <fx.lebail@...oo.com>; "netdev@...r.kernel.org" <netdev@...r.kernel.org> > Cc: David Stevens <dlstevens@...ibm.com>; Bill Fink <billfink@...dspring.com>; Hannes Frederic Sowa <hannes@...essinduktion.org>; David S. Miller <davem@...emloft.net>; Alexey Kuznetsov <kuznet@....inr.ac.ru>; James Morris <jmorris@...ei.org>; Hideaki Yoshifuji <yoshfuji@...ux-ipv6.org>; Patrick McHardy <kaber@...sh.net> > Sent: Thursday, February 6, 2014 3:01 PM > Subject: Re: [PATCH net-next v2] ipv6: enable anycast addresses as source addresses in ICMPv6 error messages > > Le 06/02/2014 13:38, François-Xavier Le Bail a écrit : >>> From: Nicolas Dichtel <nicolas.dichtel@...nd.com> >> >> >>> Subject: Re: [PATCH net-next v2] ipv6: enable anycast addresses as > source addresses in ICMPv6 error messages >>> >>> Le 19/01/2014 17:00, Francois-Xavier Le Bail a écrit : >>> >>>> - Uses ipv6_anycast_destination() in icmp6_send(). >>>> >>>> Suggested-by: Bill Fink <billfink@...dspring.com> >>>> Signed-off-by: Francois-Xavier Le Bail > <fx.lebail@...oo.com> >>> This patch causes an Oops on my target. >> >> What is your target ? > x86 32bits > >> >>> Here is the step to reproduce it: >>> modprobe sit >>> ip link add sit1 type sit remote 10.16.0.121 local 10.16.0.249 >>> ip l s sit1 up >>> ip -6 a a dev sit1 2001:1234::123 remote 2001:1234::121 >>> ping6 2001:1234::121 >> >> I cannot reproduce this in my target (updated net-next x86_64) and >> iproute2 from git. > I use linus tree (3.14-rc1+). > >> Can you send me your config file ? > See attachment. > > >> >>> The problem is that ipv6_anycast_destination() uses unconditionally >>> skb_dst(skb), which is NULL in this case. >>> >>> Not sure what is the best way to fix this, any suggestions? >> >> I will try to reproduce first and see. > Note that the peer was not set up, hence the ping didn't work. > ipip6_err() calls ipip6_err_gen_icmpv6_unreach() which will drop the dst > before calling icmpv6_send(). > > > Here is the backtrace: > [ 387.786155] BUG: unable to handle kernel NULL pointer dereference at 00000096 > [ 387.787291] IP: [<c12f1568>] icmp6_send+0x79/0x596 [...] > [ 387.790055] [<f85ce03b>] ? tunnel64_err+0x16/0x25 [tunnel4] Thanks for these informations. Can you test an alternative replacing: test on: ipv6_anycast_destination(skb) by test on: ipv6_chk_acast_addr_src(net, skb->dev, &hdr->daddr) Greetings -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists