Subject: CVE-2024-36929: net: core: reject skb_copy(_expand) for fraglist GSO skbs

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

net: core: reject skb_copy(_expand) for fraglist GSO skbs

SKB_GSO_FRAGLIST skbs must not be linearized, otherwise they become
invalid. Return NULL if such an skb is passed to skb_copy or
skb_copy_expand, in order to prevent a crash on a potential later
call to skb_gso_segment.

The Linux kernel CVE team has assigned CVE-2024-36929 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 5.6 with commit 3a1296a38d0c and fixed in 5.10.217 with commit faa83a7797f0
	Issue introduced in 5.6 with commit 3a1296a38d0c and fixed in 5.15.159 with commit c7af99cc2192
	Issue introduced in 5.6 with commit 3a1296a38d0c and fixed in 6.1.91 with commit 989bf6fd1e1d
	Issue introduced in 5.6 with commit 3a1296a38d0c and fixed in 6.6.31 with commit cfe34d86ef97
	Issue introduced in 5.6 with commit 3a1296a38d0c and fixed in 6.8.10 with commit aea5e2669c28
	Issue introduced in 5.6 with commit 3a1296a38d0c and fixed in 6.9 with commit d091e579b864

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-36929
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	net/core/skbuff.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/faa83a7797f06cefed86731ba4baa3b4dfdc06c1
	https://git.kernel.org/stable/c/c7af99cc21923a9650533c9d77265c8dd683a533
	https://git.kernel.org/stable/c/989bf6fd1e1d058e73a364dce1a0c53d33373f62
	https://git.kernel.org/stable/c/cfe34d86ef9765c388f145039006bb79b6c81ac6
	https://git.kernel.org/stable/c/aea5e2669c2863fdd8679c40ee310b3bcaa85aec
	https://git.kernel.org/stable/c/d091e579b864fa790dd6a0cd537a22c383126681