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 D461E58F09F for ; Fri, 11 Sep 2026 20:04:02 +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=1789157047; cv=none; b=Dlb3wvxpZZcNzc1DdsAiQdCTh3khiK0KEcfxEt6RMt6DG7e/ya6tbGWiDlfpAzZ15wLEj8J74vw42jqnXHZy9rIEKRH8samUaY7xCGdSqGv9AVWafiedCbUMbboNikKhJmNDY874ITmLEgfZzIeueSzN1bV++F3yjz7PVtCp+x0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789157047; c=relaxed/simple; bh=JeBSXdMHwSkDkRVVWR5fSrIkqah40H2BJNfEJKKUQH0=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=g8Z9J4BYUXpDyIJX7Shf7Lcef9UWjH8caG14KMw0MNd0GvLpwE7WQGe1TNdHBPLjYybe7vPxwZ4WPsa9MgXR1Rn5lSz3evAcWah0Vq9WVEG0iXh/xvPgCDrtgQdqmR3fvRXh2KOwp8162J7NusW4g8v1BFwgyscX4cgbOLrFsW4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=1kGKCMVM; 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="1kGKCMVM" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 35BD21F00898; Fri, 11 Sep 2026 20:04:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789157042; bh=CPDG0+jrdSqasGdkOXrswUz2JIkNbmNRG+equEP7sWU=; h=From:To:Cc:Subject:Date:Reply-To; b=1kGKCMVMukIlYXZB1QGFI79iedMoRq3bOQkMBDNyS+hXuPXSmGB33y9HPajwdDNh2 XJX4O8jblaZNVyEgnJOJqymXEuWWNQqXjIR/FkA3SHKKQ7RuXZWMFAVtdobBm2/E0o DaUm58rRrkIV9mSmOLRb7MT5NLpiInaAHKSIRgHA= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-89718: zram: fix out-of-bounds access in writeback_store() Date: Fri, 11 Sep 2026 21:46:47 +0200 Message-ID: <2026091159-CVE-2026-89718-7a26@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=2949; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=urZy7mkwrWrNSrBSkhdW4GwkVsyZ2UBllWthd33/hGI=; b=owGbwMvMwCRo6H6F97bub03G02pJDFlLItsrXjnwX/y5l0/prXF0gVtAGqsq+/XPC7pmWES1X /jzR2dBRywLgyATg6yYIsuXbTxH91ccUvQytD0NM4eVCWQIAxenAEzkRTDD/DzTMzzFRzZXu1Y+ 02o9J7bA1TA/gWHBEYGJN0RWpNUtTPvyzk6wuYVTyK8CAA== 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 out-of-bounds access in writeback_store() Patch series "zram: fix stale scan bounds after reinitialization". Both writeback_store() and read_block_state() derive their table scan bounds from zram->disksize before acquiring dev_lock. If the device is reset and reinitialized with a smaller disksize between that read and lock acquisition, the bound can describe the old table while the scan operates on the new one. This can lead to out-of-bounds slot accesses. Move both bound calculations under dev_lock so each bound remains consistent with the table throughout its scan. Keep the fixes separate because the affected interfaces originate from different commits and can be backported independently. This patch (of 2): writeback_store() calculates the table scan bounds before taking dev_lock. A reset followed by reconfiguration with a smaller disksize can therefore replace zram->table while writeback_store() is waiting for the lock. Once it acquires the lock, it sees an initialized device but scans the new table using the old upper bound, resulting in an out-of-bounds access. Calculate the number of pages while holding dev_lock so the scan bound matches the table protected by the lock. The Linux kernel CVE team has assigned CVE-2026-89718 to this issue. Affected and fixed versions =========================== Issue introduced in 5.0 with commit a939888ec38bf1f33e4a903056677e92a4844244 and fixed in 7.2.4 with commit 07a82a66f8c1894d92e51d97542c32ebf2c51b09 Issue introduced in 5.0 with commit a939888ec38bf1f33e4a903056677e92a4844244 and fixed in 7.3-rc1 with commit 894913e2d35c46ff19a77530907771ae57862b96 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-2026-89718 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 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/07a82a66f8c1894d92e51d97542c32ebf2c51b09 https://git.kernel.org/stable/c/894913e2d35c46ff19a77530907771ae57862b96