From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-cve-announce@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@kernel.org>
Subject: CVE-2026-90102: NFSv4/pnfs: key the data server cache on the NFS version
Date: Thu, 17 Sep 2026 17:08:52 +0100 [thread overview]
Message-ID: <2026091713-CVE-2026-90102-0bc4@gregkh> (raw)
From: Greg Kroah-Hartman <gregkh@kernel.org>
Description
===========
In the Linux kernel, the following vulnerability has been resolved:
NFSv4/pnfs: key the data server cache on the NFS version
nfs4_pnfs_ds_add() keys the per-net data server cache on the multipath
address set alone, and struct nfs4_pnfs_ds records no version. That
suffices for the files layout driver, which always connects with version
4, but flexfiles takes its version tuple from GETDEVICEINFO per device,
and one address can legitimately serve both NFSv3 and NFSv4.
Two deviceids on one address with different ds_versions[0].version
therefore share a single nfs4_pnfs_ds, and whichever mirror connects
first pins ds_clp to its own version. The other one is handed that
client anyway, so it selects rpc_call_ops for a version the connection
does not speak, and the mismatched sequence-slot handling dereferences
NULL.
Add the version to the cache key so the two cannot alias, giving each
version its own nfs4_pnfs_ds and connection while both mirrors stay
usable. Only the major version is compared, since that is what selects
rpc_call_ops and rpc_ops; v4.0 and v4.1 keep sharing a client. The files
layout driver passes the 4 it already hardcodes at connect time.
The Linux kernel CVE team has assigned CVE-2026-90102 to this issue.
Affected and fixed versions
===========================
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 5.10.270 with commit ffb100b0da0e217d5d63ce6fe092f9c29e59f7dd
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 5.15.221 with commit 02e160922bc83cd25e346a028ed43cbdb0b57e1a
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 6.1.188 with commit bc7aa9d8aff826031ffe25eba7f2f3acafcbf7a1
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 6.6.157 with commit dd5bd091daa48c6ed8f9235ddf448aa288a0881f
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 6.12.110 with commit f2994ba1263d9e88d3d9ae1d097c5cf811d4bfa5
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 6.18.52 with commit 27f640cd92eebf5c2f64336be7ca24f4636390cb
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 7.2.6 with commit bbc975cfb07a146843fde1126c43441e76177539
Issue introduced in 4.0 with commit d67ae825a59d639e4d8b82413af84d854617a87e and fixed in 7.3-rc1 with commit 13c23c5cb977f66390795437fd3837887ce1fd75
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-2026-90102
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/nfs/filelayout/filelayoutdev.c
fs/nfs/flexfilelayout/flexfilelayoutdev.c
fs/nfs/pnfs.h
fs/nfs/pnfs_nfs.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/ffb100b0da0e217d5d63ce6fe092f9c29e59f7dd
https://git.kernel.org/stable/c/02e160922bc83cd25e346a028ed43cbdb0b57e1a
https://git.kernel.org/stable/c/bc7aa9d8aff826031ffe25eba7f2f3acafcbf7a1
https://git.kernel.org/stable/c/dd5bd091daa48c6ed8f9235ddf448aa288a0881f
https://git.kernel.org/stable/c/f2994ba1263d9e88d3d9ae1d097c5cf811d4bfa5
https://git.kernel.org/stable/c/27f640cd92eebf5c2f64336be7ca24f4636390cb
https://git.kernel.org/stable/c/bbc975cfb07a146843fde1126c43441e76177539
https://git.kernel.org/stable/c/13c23c5cb977f66390795437fd3837887ce1fd75
reply other threads:[~2026-09-17 16:14 UTC|newest]
Thread overview: [no followups] expand[flat|nested] mbox.gz Atom feed
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=2026091713-CVE-2026-90102-0bc4@gregkh \
--to=gregkh@linuxfoundation.org \
--cc=cve@kernel.org \
--cc=gregkh@kernel.org \
--cc=linux-cve-announce@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.