linux-cve-announce - CVE-2024-50094: sfc: Don't invoke xdp_do

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: <2024110551-CVE-2024-50094-5963@gregkh>
Date: Tue,  5 Nov 2024 18:04:54 +0100
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
Subject: CVE-2024-50094: sfc: Don't invoke xdp_do_flush() from netpoll.

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

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

sfc: Don't invoke xdp_do_flush() from netpoll.

Yury reported a crash in the sfc driver originated from
netpoll_send_udp(). The netconsole sends a message and then netpoll
invokes the driver's NAPI function with a budget of zero. It is
dedicated to allow driver to free TX resources, that it may have used
while sending the packet.

In the netpoll case the driver invokes xdp_do_flush() unconditionally,
leading to crash because bpf_net_context was never assigned.

Invoke xdp_do_flush() only if budget is not zero.

The Linux kernel CVE team has assigned CVE-2024-50094 to this issue.

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

	Issue introduced in 6.11 with commit 401cb7dae813 and fixed in 6.11.4 with commit 65d4fc76d75c
	Issue introduced in 6.11 with commit 401cb7dae813 and fixed in 6.12-rc3 with commit 55e802468e1d

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-2024-50094
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:
	drivers/net/ethernet/sfc/efx_channels.c
	drivers/net/ethernet/sfc/siena/efx_channels.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/65d4fc76d75c136744e67754d20feda609e7b793
	https://git.kernel.org/stable/c/55e802468e1d38dec8e25a2fdb6078d45b647e8c