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 6653E4915A1 for ; Fri, 25 Sep 2026 10:26:53 +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=1790332014; cv=none; b=BV5DB/7Eie70TqjCVBNunQwlT+FKCEPF8Tz6MUFnnUN6yGflXiMysv9FXC81g07q8Rj3CPoeBESzsdXvcQm7NZFIYd3+xPD8WCm722djkWTfaPCJdeER2cVvJWHObPTJ7jZRnOnvpQIdK/kJldlNyef9RsLHa4YBry0J4Gw/FI8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790332014; c=relaxed/simple; bh=7aWvEt3WwHJx3YPnTE00q+H2TJq0zQThGZaGZJ9qkS4=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=ceWTiJaaA/WQCvo1ZAUh5a3Nkep0ZcoOuKm0Re4oodG2WPxOG+H0wyDJqfRj3wnEwmWCoA1MwKxqz4AtVdPCq83/0TQvnhPbfz+n+4JBy1jlCKFxL/SUz6UaXQ9qqCk+Jfvo0xK0691rsQdfEjnBrs8lLS/URCfEtGlG56WHpOE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=spSWslzb; 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="spSWslzb" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BF1CC1F000FF; Fri, 25 Sep 2026 10:26:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1790332013; bh=Lt577fToIcSxWzZ2afUyP7Z5B4DjMQM7cgnVMxNd11s=; h=From:To:Cc:Subject:Date:Reply-To; b=spSWslzb5/hQl1RA/d4R74rO+W8pGjFMMr6g/9mWtA7oqwge1TJgSKBBnwoN2jOdd DewK4rlKySSGRuFaQgcU+Rm7zJ8Um7aXl5yZWi7zCNXAB5/xvYQglyrgVvlmkd0S17 0/J7S7zSb0ShFKviB2lfsCMfoQUKwUck87RUA3KY= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-97610: netfs: Fix uninitialized return value in netfs_unbuffered_write() Date: Fri, 25 Sep 2026 12:23:10 +0200 Message-ID: <2026092502-CVE-2026-97610-3bbd@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=2650; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=FdZfGaMuWhFmykakFpzEl4ZJOo2QSzx9Q0jZiGnrI/c=; b=owGbwMvMwCRo6H6F97bub03G02pJDFnbvL1YirkE1tr2GRb1f9ZKzDzU1rlg+UvZ22Vv3h+wE 3ilwRbdEcvCIMjEICumyPJlG8/R/RWHFL0MbU/DzGFlAhnCwMUpABPZXMkwT+OWBH/X2Q/Fne/7 frgLHq9hSVV4yLCgX3SjHJ+C7h7LqAtTOTs+3/10WsUNAA== 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: netfs: Fix uninitialized return value in netfs_unbuffered_write() If preparation of the first subrequest fails, netfs_unbuffered_write() exits its loop before ret is initialized. The empty-iterator check can do the same. For synchronous writes, netfs_unbuffered_write_iter_locked() may then return an unrelated error instead of wreq->error. This is reachable through CIFS if cifs_prepare_write() fails to reopen the file or obtain credits. Initialize ret to 0 so the caller returns wreq->error if no data was written, or the number of bytes already written otherwise. Found with Clang's -Wconditional-uninitialized. The Linux kernel CVE team has assigned CVE-2026-97610 to this issue. Affected and fixed versions =========================== Issue introduced in 6.18.17 with commit 72d08d2839649d1c5efbe375751f4473fa4486af and fixed in 6.18.53 with commit 3d038eebdbd400c3bc4b66bd8aa0dff0c2bcce26 Issue introduced in 7.0 with commit a0b4c7a49137ed21279f354eb59f49ddae8dffc2 and fixed in 7.2.7 with commit 2e38d500471d097cda87d7d374bbc1b13493075d Issue introduced in 7.0 with commit a0b4c7a49137ed21279f354eb59f49ddae8dffc2 and fixed in 7.3-rc3 with commit f18e8774f4d3137fa0a5fb8ffa83d59a719666d8 Issue introduced in 6.19.7 with commit 0c29f6d63122a0168d67cb8ecde5b4cf7fe4acb0 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-2026-97610 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/netfs/direct_write.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/3d038eebdbd400c3bc4b66bd8aa0dff0c2bcce26 https://git.kernel.org/stable/c/2e38d500471d097cda87d7d374bbc1b13493075d https://git.kernel.org/stable/c/f18e8774f4d3137fa0a5fb8ffa83d59a719666d8