|Description||Linux kernel: Exploitable memory corruption due to UFO to non-UFO path switch. When building a UFO packet with MSG_MORE __ip_append_data() calls ip_ufo_append_data() to append. However in between two send() calls, the append path can be switched from UFO to non-UFO one, which leads to a memory corruption. In case UFO packet lengths exceeds MTU, copy = maxfraglen - skb->len becomes negative on the non-UFO path and the branch to allocate new skb is taken. This triggers fragmentation and computation of fraggap = skb_prev->len - maxfraglen. Fraggap can exceed MTU, causing copy = datalen - transhdrlen - fraggap to become negative. Subsequently skb_copy_and_csum_bits() writes out-of-bounds. A similar issue is present in IPv6 code. The bug was introduced in e89e9cf539a2 ("[IPv4/IPv6]: UFO Scatter-gather approach") on Oct 18 2005.|
|Source||CVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, Mageia, GitHub advisories/code/issues, web search, more)|
Vulnerable and fixed packages
The table below lists information on source packages.
The information below is based on the following data on fixed versions.
[wheezy] - linux <ignored> (Low severity and difficult to backport)
Introduced by: https://git.kernel.org/linus/e89e9cf539a28df7d0eb1d0a545368e9920b34ac (2.6.15-rc1)
Fixed by: https://git.kernel.org/linus/85f1bd9a7b5a79d5baa8bf44af19658f7bf77bfa