netdev - [BUG] net:ipv6/ip6_tunnel: A double free in ip6_tnl_start

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>] [day] [month] [year] [list]

Date:   Tue, 27 Apr 2021 10:06:54 +0800 (GMT+08:00)
From:   lyl2019@...l.ustc.edu.cn
To:     davem@...emloft.net, yoshfuji@...ux-ipv6.org, dsahern@...nel.org,
        kuba@...nel.org
Cc:     netdev@...r.kernel.org, linux-kernel@...r.kernel.org
Subject: [BUG] net:ipv6/ip6_tunnel:  A double free in ip6_tnl_start_xmit

Hi, maintainer.
    Our code analyzer reported a double free bug,
and it is a little difficult for me to fix the intricate bug.

File: net/ipv6/ip6_tunnel.c

 In ip6_tnl_start_xmit, it calls ipxip6_tnl_xmit() and then
ipxip6_tnl_xmit calls ip6_tnl_xmit(). The skb could be freed
at line 1,213 via consume_skb(skb). If ip6_tnl_xmit() returns
an error code, the tx_err branch of ip6_tnl_start_xmit will free
the skb again.

Issue: e7bb18e6c8b7e ("ip6_tunnel: simplify transmit path")
Signed-off-by: Lv Yunlong <lyl2019@...l.ustc.edu.cn>