CVE-2026-72319: ipvs: ensure inner headers in ICMP errors are in headroom

CVE-2026-72319: ipvs: ensure inner headers in ICMP errors are in headroom

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

ipvs: ensure inner headers in ICMP errors are in headroom

Sashiko points out that after stripping the outer headers
with pskb_pull() we should ensure the inner IP headers
in ICMP errors from tunnels are present in the skb headroom
for functions like ipv4_update_pmtu(), icmp_send() and
IP_VS_DBG().

Also, add more checks for the length of the inner headers.

The Linux kernel CVE team has assigned CVE-2026-72319 to this issue.


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

	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 5.10.261 with commit 19657b3a17b774ae4e2f2635b5ae8638c9344a40
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 5.15.212 with commit dac813101914c21219ac221a60a31a11bc90e7ec
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 6.1.178 with commit dd22f74a09e25ca298ced0a3763ef353242cb78d
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 6.6.145 with commit 9bc9b95aee2b2e3f1301a16a67ee504960402875
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 6.12.97 with commit a735f9964a3d9ed97daf9b08507f8b5bcafe6326
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 6.18.40 with commit 8f48cfe657409fb5c7ba0521b14da6d47546d9cf
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 7.1.5 with commit 92185d6f7819bc558939ae83de7b1abe90e3b5c2
	Issue introduced in 3.7 with commit f2edb9f7706dcb2c0d9a362b2ba849efe3a97f5e and fixed in 7.2-rc3 with commit 3f7a535ff0fa627a0132803e4c2f903ceffcbc1c

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-2026-72319
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/netfilter/ipvs/ip_vs_core.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/19657b3a17b774ae4e2f2635b5ae8638c9344a40
	https://git.kernel.org/stable/c/dac813101914c21219ac221a60a31a11bc90e7ec
	https://git.kernel.org/stable/c/dd22f74a09e25ca298ced0a3763ef353242cb78d
	https://git.kernel.org/stable/c/9bc9b95aee2b2e3f1301a16a67ee504960402875
	https://git.kernel.org/stable/c/a735f9964a3d9ed97daf9b08507f8b5bcafe6326
	https://git.kernel.org/stable/c/8f48cfe657409fb5c7ba0521b14da6d47546d9cf
	https://git.kernel.org/stable/c/92185d6f7819bc558939ae83de7b1abe90e3b5c2
	https://git.kernel.org/stable/c/3f7a535ff0fa627a0132803e4c2f903ceffcbc1c