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 19E50582B91 for ; Fri, 11 Sep 2026 19:52:47 +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=1789156378; cv=none; b=XU0PAlCDMP9vJnukPiLgTPwcJ+OVEOvgVY5nGVnbsUDAF2F1ek+1pYmrj2W8zNcP8xTQ8aidGT7AEPbRcNTY7bEftrC7G220dN7ZjJRuC+LGcoHMj1FEJalKei80Nd3sSqpti7A71sHiIMXKBwO5umgWie+e9OtvKb36Y215w58= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789156378; c=relaxed/simple; bh=HT7nSPe0XiHe7YYutt91qHj7lOjvNO8sOMUbyghZMUE=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=oZiI/IfPRcBPODB7Lki6KQp18mNciPReW5AdyeBNVxrmF+9pAKorlQVFL7yEYyXsAYrvSwhyvVDVgSKj5gpz6eaH2GIsPw7gAzpxvZYDzLV+wgCgylFU+AMeCCT3r2Je1xshlZuX+wGkjZdPtphILXc7Q2vMWqnb7khx2S+yPj8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=0QcUKY4Y; 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="0QcUKY4Y" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B5B0B1F00899; Fri, 11 Sep 2026 19:52:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789156366; bh=IrLHOIMcKFYhLkKFPq6BSlNvD/PfZ1OUbYTQQI0+pC8=; h=From:To:Cc:Subject:Date:Reply-To; b=0QcUKY4YxS5jdzJR5PvdLTQKNwi+XCdKHjx4AmMEKGLPwRpyT2jUkw0U9OcnHBcmH 9DGFMbf1fD7D8ywrdMst/1bwZHkfy838wvdqY63At3/+yVNlvxx9/i7piUCAPRQVXq 5mIR+IMWl01dkX1IH7XHh4qyu49M6KCy6ui2sg2Q= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89494: ocfs2: validate lengths in dlm_mig_lockres_handler Date: Fri, 11 Sep 2026 21:43:03 +0200 Message-ID: <2026091108-CVE-2026-89494-dc7a@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=3334; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=YwQgCPo/+UhXg7DtUEHX22tfMm6amdrcT8SyLRweCN4=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLIkMi2kVffei31fqfEVpqasDv0Cu357JXdp92eaqjb u/lvYIdsSwMgkwMsmKKLF+28RzdX3FI0cvQ9jTMHFYmkCEMXJwCMJFaFob5iU3nuj/t2GmV/s1e 6uYdxjcPAhYmMMwVu30rYEf8udOlYca8u2udNPZEymYDAA== 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: ocfs2: validate lengths in dlm_mig_lockres_handler A node receiving a DLM_MIG_LOCKRES message trusts several fields of the peer-supplied dlm_migratable_lockres without validation. num_locks and lockname_len are bounded only on the sending side, and the message is never checked to actually carry num_locks migratable_lock entries. As a result dlm_process_recovery_data() walks mres->ml[0..num_locks) past the kmalloc(data_len) copy of the message (an out-of-bounds read that ends in a BUG_ON panic), and dlm_init_lockres() copies lockname_len bytes into the fixed 32-byte o2dlm_lockname slab object (a heap out-of-bounds write). Both are reachable by any node in the domain. Validate these fields right after dlm_grab(), before anything uses them -- including the not-joined error path, which already prints mres->lockname with the unbounded lockname_len as a %.*s precision. Reject the message unless lockname_len <= DLM_LOCKID_NAME_MAX, num_locks <= DLM_MAX_MIGRATABLE_LOCKS (the bound the sender already asserts), and the payload is large enough to hold the claimed locks. Conforming recovery and migration messages are unaffected. The Linux kernel CVE team has assigned CVE-2026-89494 to this issue. Affected and fixed versions =========================== Issue introduced in 2.6.16 with commit 6714d8e86bf443f6f7af50f9d432025649f091f5 and fixed in 6.12.109 with commit f33041906885f96e190cde54e61ddc69de39e3ee Issue introduced in 2.6.16 with commit 6714d8e86bf443f6f7af50f9d432025649f091f5 and fixed in 6.18.50 with commit 50c4cc9183e11f83427efbf770f54851f4471c02 Issue introduced in 2.6.16 with commit 6714d8e86bf443f6f7af50f9d432025649f091f5 and fixed in 7.2.4 with commit a8facb1670b4a0612183198e758d9539ef628ed9 Issue introduced in 2.6.16 with commit 6714d8e86bf443f6f7af50f9d432025649f091f5 and fixed in 7.3-rc1 with commit b54e03d9b3697d25f4a0063cf717d459c5e3ad94 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-2026-89494 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/ocfs2/dlm/dlmrecovery.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/f33041906885f96e190cde54e61ddc69de39e3ee https://git.kernel.org/stable/c/50c4cc9183e11f83427efbf770f54851f4471c02 https://git.kernel.org/stable/c/a8facb1670b4a0612183198e758d9539ef628ed9 https://git.kernel.org/stable/c/b54e03d9b3697d25f4a0063cf717d459c5e3ad94