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 E4FCE3A453B for ; Sun, 18 Oct 2026 15:48:47 +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=1792338528; cv=none; b=d+cpNc7ob5i1Hmc9F7KPO2l3WJemS8M3LknwGNAx0EvyLVowwi8x5ktc4bjrRHMPfAcWV+nm4/PeoasB8uFgINhaMYoOFaWJJvUIN/VKsaW6smEvYlFmQtnNrCnPwIUvf4Roqcscz9oBy7c8d96oooWze0ghAdn8R6MI+KkZsUc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1792338528; c=relaxed/simple; bh=7BM5xJB433leabfl14iOGcvDn6V3K3jqi1boWa4ypjk=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=lOM6MilNGUgOH+7CMSRKqHgRhL+UOKmkPXLnsX3ATI4UaTKGXMxQ4XTh1W/t81JZjjWDzXghCT6cZzcaHTX46zyAprOymCsOQmiUYK3u87W8lbF03zEuaZ1+JvNu2Xlf9Sm9ua589/M2cyNXWJ1qugaRk1wjpP3wLLyhICXugwU= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=YSlcG/gU; 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="YSlcG/gU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4FEB31F000C4; Sun, 18 Oct 2026 15:48:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1792338527; bh=w5GjDHXmRnnmqTGp2LcZJDtxlZ/Lx3nuUhLmjFlX5m4=; h=From:To:Cc:Subject:Date:Reply-To; b=YSlcG/gUSMBtQxemXI5MeCoEQPhBMyOnjcMaYuSw9drdZ3Zm8CnWJNXLlXra1AApf 1g33rS2IMJsXMvhUiCgBvn3wv9vtzgydUoY149PBs128+db3T2Hqv83e0/vJgJlO0K sx6cjrS39DwYmU1R2gQpX2unCAQ1laorMSo84ZUU= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-98683: smb: client: flush dirty data before zeroing a range Date: Sun, 18 Oct 2026 17:44:18 +0200 Message-ID: <2026101801-CVE-2026-98683-9df4@gregkh> X-Mailer: git-send-email 2.56.0 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=3185; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=qXRi6cdENHRc0D4nkT6g+eBTP6WShP4MAtOKnZbcT7w=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlXXjq+5eOwYVz8r3rFcr+ePIvLpyqX5aVmvb80d8/5Q oXLPS0TOmJZGASZGGTFFFm+bOM5ur/ikKKXoe1pmDmsTCBDGLg4BWAiV6IZFuxk/nhu/qxL0T/C 6qzusPJXZde0HmJYcLAjZYXxgXrvB7d2bbku/97O7i/zYgA= 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: smb: client: flush dirty data before zeroing a range smb3_zero_range() emulates FALLOC_FL_ZERO_RANGE by invalidating the page cache over the target range with truncate_pagecache_range() and then issuing FSCTL_SET_ZERO_DATA to the server. Dirty data was only flushed conditionally, when the range reached or extended EOF. For a purely interior zero range that does not reach EOF, no flush happened, so a dirty folio overlapping the range could be written back to the server after the FSCTL and refill the range that was just zeroed with stale data. Fix this by unconditionally flushing and waiting for dirty data in the range before invalidating the page cache and issuing FSCTL_SET_ZERO_DATA, exactly as was done for smb3_punch_hole() in commit d7d2adcd022b ("smb/client: flush dirty data before punching a hole"); the two paths are structurally identical here. This is observed as generic/363 randomly reading stale data where a zeroed range is expected against Windows Server. The Linux kernel CVE team has assigned CVE-2026-98683 to this issue. Affected and fixed versions =========================== Issue introduced in 6.11 with commit 91d1dfae464987aaf6c79ff51d8674880fb3be77 and fixed in 6.18.56 with commit cecf4114069fc19629d284710fd783d56bbca862 Issue introduced in 6.11 with commit 91d1dfae464987aaf6c79ff51d8674880fb3be77 and fixed in 7.2.10 with commit e8ba21c7e6ef3d4cb617858760673877b2e4a2bb Issue introduced in 6.11 with commit 91d1dfae464987aaf6c79ff51d8674880fb3be77 and fixed in 7.3-rc6 with commit 8f8d32c1044f70e46e87550e039a15ff20a4b21c Issue introduced in 6.1.110 with commit 13af7446428771e9e529284d390e7994df8be683 Issue introduced in 6.6.51 with commit 0a9423f99ded38b32bd1864347332cc557e6b141 Issue introduced in 6.10.10 with commit 7dfa4279c55f467a88e653a5d544817181b22aea 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-2026-98683 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/smb/client/smb2ops.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/cecf4114069fc19629d284710fd783d56bbca862 https://git.kernel.org/stable/c/e8ba21c7e6ef3d4cb617858760673877b2e4a2bb https://git.kernel.org/stable/c/8f8d32c1044f70e46e87550e039a15ff20a4b21c