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 65A614EBAE1 for ; Wed, 16 Sep 2026 10:45:20 +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=1789555540; cv=none; b=W13NxkrUj6cOeD7UkYhhY9aN3nRyTR6Xok0o7eRXZEfzpAg0lDEryXrBfcJOYqh1D7etPPX4YQTtdupBAqET8Wunsw7KTPoNPv6Yd0rz5mNpBb/24zhBjv6xDN7NPYIfdtMGQT51RZsAWmr+Qhdpk4Q7LDD00RhJaB9Dr1bHNdU= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789555540; c=relaxed/simple; bh=aS55ge86/GelZxaM1odba6alaYTOu6R/2+5MH7zM+k8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=FcLlS//gAeWbhdUYvY1h06jJT3uAo+UhdKSYeQMSWKDk1KasGz8vJLK/2+UoxfddpVWLlH3aDiA0NZtzrhYzZ0jxwv7+YZmVke7KuN2N1vwM+++Qlv+vH3vDB+piHJImZw1jkUT1Og1NIIai6qfjNTzaDn6JpGwlTa+8dNZSHNc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1H4dPeNA; 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="1H4dPeNA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9851E1F00898; Wed, 16 Sep 2026 10:45:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789555520; bh=Uasr13ZaUKoUgEpPNRfJr27fm+MRv5OsA+WKonf7V7M=; h=From:To:Cc:Subject:Date:Reply-To; b=1H4dPeNApaufHbb13BoeKmVJcMGHr167DSMGjNJQ1eTetAjkWwQdnlzPGsL88Fda+ rWmMY/DHUqpHTSVxVAoIk6PJBzcy/NbQjseY/H4Z/vKIVbZR6E3unkE+RI7T3gLB2P 4k4x+ihz4BXqqP+cMiAvr3AG3JGGWoMMHHLMt6Fo= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-90043: zram: fix slot lock bit position on big-endian 64-bit Date: Wed, 16 Sep 2026 11:32:53 +0100 Message-ID: <2026091608-CVE-2026-90043-bbac@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=2400; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=+5uyBDOJyx4lowPuNiQMG+QIJ4KInrkEe5nALj0ByHY=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmr8jdw/fpq9WON0oHCZ9Ebls39pvT66Y91lxc4XJdbo pQ+9e5T0Y5YFgZBJgZZMUWWL9t4ju6vOKToZWh7GmYOKxPIEAYuTgGYiH87w/ygWb7fP9st2u15 fJlLZL14/rEs9kyGWUxz5VKLI5K6LicKyzW63YpKMHE7AwA= 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: zram: fix slot lock bit position on big-endian 64-bit The slot lock is a bit operation on the whole __lock word, which flags and ac_time alias as two u32s. On little-endian the lock bit lands in the position ZRAM_ENTRY_LOCK reserves in flags, so the aliasing works out. On 64-bit big-endian it lands in ac_time instead: with ZRAM_TRACK_ENTRY_ACTIME enabled, storing the access time from mark_slot_accessed() or slot_free() wipes out the held lock bit, letting another CPU take the same slot lock; an access time value with that bit set makes the slot look locked forever. Shift the lock bit into the flags half of the word on big-endian 64-bit. The Linux kernel CVE team has assigned CVE-2026-90043 to this issue. Affected and fixed versions =========================== Issue introduced in 7.0 with commit 2e8ff2f51dde73a26b94aed2df4827177bd25e6e and fixed in 7.2.5 with commit 052b6b2d5fe97547bd2cdb73fa894f6cfea68b11 Issue introduced in 7.0 with commit 2e8ff2f51dde73a26b94aed2df4827177bd25e6e and fixed in 7.3-rc1 with commit a8b5875741d416703e19ad8eeac6fce8a12bd6e4 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-2026-90043 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/block/zram/zram_drv.c drivers/block/zram/zram_drv.h 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/052b6b2d5fe97547bd2cdb73fa894f6cfea68b11 https://git.kernel.org/stable/c/a8b5875741d416703e19ad8eeac6fce8a12bd6e4