linux-cve-announce - CVE-2022-50345: NFSD: Protect against send buffer overflow in NFSv3 READ

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: <2025091639-CVE-2022-50345-a1ff@gregkh>
Date: Tue, 16 Sep 2025 18:11:41 +0200
From: Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To: linux-cve-announce@...r.kernel.org
Cc: Greg Kroah-Hartman <gregkh@...nel.org>
Subject: CVE-2022-50345: NFSD: Protect against send buffer overflow in NFSv3 READ

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

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

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

NFSD: Protect against send buffer overflow in NFSv3 READ

Since before the git era, NFSD has conserved the number of pages
held by each nfsd thread by combining the RPC receive and send
buffers into a single array of pages. This works because there are
no cases where an operation needs a large RPC Call message and a
large RPC Reply at the same time.

Once an RPC Call has been received, svc_process() updates
svc_rqst::rq_res to describe the part of rq_pages that can be
used for constructing the Reply. This means that the send buffer
(rq_res) shrinks when the received RPC record containing the RPC
Call is large.

A client can force this shrinkage on TCP by sending a correctly-
formed RPC Call header contained in an RPC record that is
excessively large. The full maximum payload size cannot be
constructed in that case.

The Linux kernel CVE team has assigned CVE-2022-50345 to this issue.

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

	Fixed in 5.10.220 with commit c23687911f82a63fa2977ce9c992b395e90f8ba0
	Fixed in 5.15.75 with commit 75d9de25a6f833dd0701ca546ac926cabff2b5af
	Fixed in 5.19.17 with commit bc6c0ed253cd4763dba7541d558e4b704f33176f
	Fixed in 6.0.3 with commit 309f29361b6bfae96936317376f1114568c5de19
	Fixed in 6.1 with commit fa6be9cc6e80ec79892ddf08a8c10cabab9baf38

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-2022-50345
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:
	fs/nfsd/nfs3proc.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/c23687911f82a63fa2977ce9c992b395e90f8ba0
	https://git.kernel.org/stable/c/75d9de25a6f833dd0701ca546ac926cabff2b5af
	https://git.kernel.org/stable/c/bc6c0ed253cd4763dba7541d558e4b704f33176f
	https://git.kernel.org/stable/c/309f29361b6bfae96936317376f1114568c5de19
	https://git.kernel.org/stable/c/fa6be9cc6e80ec79892ddf08a8c10cabab9baf38