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 658D251C321 for ; Fri, 11 Sep 2026 19:50:55 +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=1789156263; cv=none; b=B0BAlT0CgufFdHn6XPlFP/bXtrTFijJHXm8eU+7V3Zrlm0+BSJYGvKKeZQkASsg4vek9vjsmyUF9DPHQItXKoF2lSA9e5ud7q+7wSuAT1CO95J7CR2YgbEmaI1FAcfnvT2Of5H8SCsigW4+UBHztKgJkfzdyqFE/hy5uXFINSC0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156263; c=relaxed/simple; bh=Bwjs+NR8L/ZULy9HLurPp2asGE7hbde6jD/UjXtir4U=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=exu7nCM9i4tBtvjXin4Jy/0hUP4nEeUBzApIILkI758QyZAsh2RcSZQsO66+NvKlQxr9Y9W5KnB7Ay6GxcyXhgISABOapqWk/a6lTvoxUnecOb1LukFoVnwvW3I2qX14AqMj5pH3c4TeoqWVS2t6z0vNBs9yTTaSdnk04UYLveM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=OjfpEDnz; 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="OjfpEDnz" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D4FC1F00898; Fri, 11 Sep 2026 19:50:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156254; bh=TfCkBCIzw/FnxAezrYZMeKaQmDvUmNKvoXjdkiEQU38=; h=From:To:Cc:Subject:Date:Reply-To; b=OjfpEDnzJIu3iMlKEDn9gnzArR5xmzRacu2eE40O7WR3xadU5tlipqDQ/Sm0/va6J sPyfIbYdmtpxzOUMguBkuLRjKoX2pmFtLUX43M+SiJcgRKPqn4P7iwenQKZHOrfDP7 YRZA7MA5UFeT18UmvfxJ7PmAvojbe/KidEKuvRv0= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89456: s390/dasd: Propagate partial completion length across ERP recovery Date: Fri, 11 Sep 2026 21:42:25 +0200 Message-ID: <2026091159-CVE-2026-89456-74dc@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=3012; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=Vhr4XRe5WorOwVjyll5j1OStP5Y4zOKO+Fxfh1hiqUU=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIn16q9/elWYy9LuyNdxiiY3Q5etMga7tSwve+J05O f2gxbqPHbEsDIJMDLJiiixftvEc3V9xSNHL0PY0zBxWJpAhDFycAjCRgwIM8xN8VIq3nwh41G+R 69PIVH83L/Z7PMOCuV4OPpmbtrctEHkTE9POfeYVT6YFAA== 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: s390/dasd: Propagate partial completion length across ERP recovery dasd_default_erp_postaction() copies the timing and device state from the finished ERP request back to the original request but drops proc_bytes. A request that was partially completed, an ESE read of a not-yet-allocated track returns fewer bytes than requested, and then recovered through the ERP chain loses its partial-completion length. __dasd_cleanup_cqr() then sees proc_bytes == 0 and completes the whole request instead of requeueing the remainder, silently returning zeroed data for the part that was never read. Carry proc_bytes over to the original request like the other per-request state. The Linux kernel CVE team has assigned CVE-2026-89456 to this issue. Affected and fixed versions =========================== Issue introduced in 5.6 with commit 5e6bdd37c5526ef01326df5dabb93011ee89237e and fixed in 6.12.109 with commit d6b8778b1b82aa3a8dbf8612080f635b834bd16b Issue introduced in 5.6 with commit 5e6bdd37c5526ef01326df5dabb93011ee89237e and fixed in 6.18.50 with commit ceafb262475ac6cb3a7d07b1102608be2b216b99 Issue introduced in 5.6 with commit 5e6bdd37c5526ef01326df5dabb93011ee89237e and fixed in 7.2.4 with commit 15ec03452c18e8d288e519837d21b308300d74b2 Issue introduced in 5.6 with commit 5e6bdd37c5526ef01326df5dabb93011ee89237e and fixed in 7.3-rc1 with commit 6fb5ba2e7e43173a3761e46f091070a8185efa14 Issue introduced in 5.4.26 with commit fbbacd0dcbc3ae9398c569dbea96ae4b5ad97e04 Issue introduced in 5.5.10 with commit 5f7c9989f11305aaa43e0f4378f4f070022a9f2b 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-2026-89456 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: drivers/s390/block/dasd_erp.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/d6b8778b1b82aa3a8dbf8612080f635b834bd16b https://git.kernel.org/stable/c/ceafb262475ac6cb3a7d07b1102608be2b216b99 https://git.kernel.org/stable/c/15ec03452c18e8d288e519837d21b308300d74b2 https://git.kernel.org/stable/c/6fb5ba2e7e43173a3761e46f091070a8185efa14