From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 27E984534AD for ; Fri, 11 Sep 2026 20:01:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156921; cv=none; b=hKKqr9YZbKX2djNPuSs99RxEc/77w29t/i2n/Zfl2Oix+HlU83UopquOC3CXLyLbd6Oht5QWO9ExUtfWNbQCq8R2ojI/WZL6YYiKT2jCt40q4+hwhBxA773jSD88ajaRmmj/pAFR69OYJDFMBEXs7SbVMkdmJxSlXew9D/Vzw6g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156921; c=relaxed/simple; bh=4iTjfF8CHan63C6ctSBfIxtjchd5dgOC+yUGud0/pC0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=tH0yNxwP9jccVfCEuaplbRkn2VVutVVnBkoDbflQI/K7dxHg5bR/9hP6v+2Fzf0OsW4wU8pDXrzhfYJe8wv8ZF+kSeQSElIqCL15diyUGi1adQjGZxhtEaI9R7lBqmtXEXk1lNhsOKJGGdTJZcjIrM1qMHKKe/IC0DNiwlZtXfM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=DaMjHhdv; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="DaMjHhdv" Received: by smtp.kernel.org (Postfix) with ESMTPSA id CFC2C1F00898; Fri, 11 Sep 2026 20:01:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156907; bh=0KmElcuoC5N1CD/f39K7I1XFxpvaWRFj8dSiXN6gZjM=; h=From:To:Cc:Subject:Date:Reply-To; b=DaMjHhdvTaADK7rNeIyABTEklMwzZ+qdCyOHFe97pPbcuHvw2Qhk9m4iPSwMCm7q5 D5MT5pA/nRyx+jkTZ0FtHxfR5829soM/mOg8pClhed9fZqrHPbWdSbEuqIsspfAKgl tVd37020sGQSDkbZRLJpXb2298XVDHcWuEV27uKQ= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89673: nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo Date: Fri, 11 Sep 2026 21:46:02 +0200 Message-ID: <2026091149-CVE-2026-89673-69d6@gregkh> X-Mailer: git-send-email 2.55.0 Reply-To: , Precedence: bulk X-Mailing-List: linux-cve-announce@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Developer-Signature: v=1; a=openpgp-sha256; l=2788; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=owWKe9Hpd3voOWZiaZwwopWdauU1ZYbGLLxQtimgzDs=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLImsn8lYY1vpO3xeYfWHBfd/d79a6H7Pe8f7lsdd/v 9WrXTJ83xHLwiDIxCArpsjyZRvP0f0VhxS9DG1Pw8xhZQIZwsDFKQATASqeZ2MX9vvt36oALTOb u+25j4KbuVb9BYrKsZh+3Dtr30e1hkdrRBfO4efkPwQA X-Developer-Key: i=gregkh@linuxfoundation.org; a=openpgp; fpr=F4B60CC5BF78C2214A313DCB3147D40DDB2DFB29 Content-Transfer-Encoding: 8bit From: Greg Kroah-Hartman Description =========== In the Linux kernel, the following vulnerability has been resolved: nfsd: fix XDR padding calculation in ff_encode_getdeviceinfo nfsd4_ff_encode_getdeviceinfo() computes the da_addr_body reservation as 16 + netid_len + addr_len, but the subsequent xdr_encode_opaque() calls emit 8 + round_up(netid_len, 4) + round_up(addr_len, 4) bytes. The mismatch means the declared da_addr_body length exceeds the actual encoded data by 2-8 bytes on every flexfile GETDEVICEINFO reply, leaking stale reply-page content to the client and mis-aligning the subsequent version list decode. Use xdr_align_size() for each string length to match what xdr_encode_opaque() actually writes. The Linux kernel CVE team has assigned CVE-2026-89673 to this issue. Affected and fixed versions =========================== Issue introduced in 6.4.16 with commit efcae97fa425ca6db9d126e37daccf2d7225cb09 and fixed in 6.12.109 with commit 74015b7be806ad9e21d46f7bd2831df280c6c783 Issue introduced in 6.4.16 with commit efcae97fa425ca6db9d126e37daccf2d7225cb09 and fixed in 6.18.50 with commit 41ebca28e17f84293650598f86bd69532ec1a8e0 Issue introduced in 6.4.16 with commit efcae97fa425ca6db9d126e37daccf2d7225cb09 and fixed in 7.2.4 with commit 62e5949f0dd5ec837af144860ff908369df4c7c9 Issue introduced in 6.4.16 with commit efcae97fa425ca6db9d126e37daccf2d7225cb09 and fixed in 7.3-rc1 with commit 8b989aaec85e1293a871d602590c951fe44b8647 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-2026-89673 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/flexfilelayoutxdr.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/74015b7be806ad9e21d46f7bd2831df280c6c783 https://git.kernel.org/stable/c/41ebca28e17f84293650598f86bd69532ec1a8e0 https://git.kernel.org/stable/c/62e5949f0dd5ec837af144860ff908369df4c7c9 https://git.kernel.org/stable/c/8b989aaec85e1293a871d602590c951fe44b8647