netdev - Re: [PATCH v3] ip6mr: Fix skb_under_panic in ip6mr_cache

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 linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date: Tue, 1 Aug 2023 18:52:00 -0600
From: David Ahern <dsahern@...nel.org>
To: Jakub Kicinski <kuba@...nel.org>, Eric Dumazet <edumazet@...gle.com>
Cc: Yue Haibing <yuehaibing@...wei.com>, davem@...emloft.net,
 pabeni@...hat.com, yoshfuji@...ux-ipv6.org, netdev@...r.kernel.org,
 linux-kernel@...r.kernel.org, simon.horman@...igine.com
Subject: Re: [PATCH v3] ip6mr: Fix skb_under_panic in ip6mr_cache_report()

On 8/1/23 2:11 PM, Jakub Kicinski wrote:
> On Tue, 1 Aug 2023 09:51:29 +0200 Eric Dumazet wrote:
>>> -               skb_push(skb, -skb_network_offset(pkt));
>>> +               __skb_pull(skb, skb_network_offset(pkt));
>>>
>>>                 skb_push(skb, sizeof(*msg));
>>>                 skb_reset_transport_header(skb);  
>>
>> Presumably this code has never been tested :/
> 
> Could have been tested on 32bit, I wonder if there is more such bugs :S

that pattern shows up a few times:

net/ipv4/ah4.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv4/esp4.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv4/esp4_offload.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv4/esp4_offload.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv4/xfrm4_tunnel.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/ah6.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/esp6.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/esp6_offload.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/esp6_offload.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/ip6mr.c:		skb_push(skb, -skb_network_offset(pkt));
net/ipv6/mip6.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/mip6.c:	skb_push(skb, -skb_network_offset(skb));
net/ipv6/xfrm6_tunnel.c:	skb_push(skb, -skb_network_offset(skb));
net/xfrm/xfrm_ipcomp.c:	skb_push(skb, -skb_network_offset(skb));