linux-cve-announce - CVE-2022-49975: bpf: Don't redirect packets with invalid pkt

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]

Message-ID: <2025061819-CVE-2022-49975-89e6@gregkh>
Date: Wed, 18 Jun 2025 13:00:40 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2022-49975: bpf: Don't redirect packets with invalid pkt_len

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

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

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

bpf: Don't redirect packets with invalid pkt_len

Syzbot found an issue [1]: fq_codel_drop() try to drop a flow whitout any
skbs, that is, the flow->head is null.
The root cause, as the [2] says, is because that bpf_prog_test_run_skb()
run a bpf prog which redirects empty skbs.
So we should determine whether the length of the packet modified by bpf
prog or others like bpf_prog_test is valid before forwarding it directly.

The Linux kernel CVE team has assigned CVE-2022-49975 to this issue.


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

	Fixed in 5.4.212 with commit 8b68e53d56697a59b5c53893b53f508bbdf272a0
	Fixed in 5.10.141 with commit 6204bf78b2a903b96ba43afff6abc0b04d6e0462
	Fixed in 5.15.65 with commit a75987714bd2d8e59840667a28e15c1fa5c47554
	Fixed in 5.19.7 with commit 72f2dc8993f10262092745a88cb2dd0fef094f23
	Fixed in 6.0 with commit fd1894224407c484f652ad456e1ce423e89bb3eb

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-2022-49975
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:
	include/linux/skbuff.h
	net/bpf/test_run.c
	net/core/dev.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/8b68e53d56697a59b5c53893b53f508bbdf272a0
	https://git.kernel.org/stable/c/6204bf78b2a903b96ba43afff6abc0b04d6e0462
	https://git.kernel.org/stable/c/a75987714bd2d8e59840667a28e15c1fa5c47554
	https://git.kernel.org/stable/c/72f2dc8993f10262092745a88cb2dd0fef094f23
	https://git.kernel.org/stable/c/fd1894224407c484f652ad456e1ce423e89bb3eb