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 7707E3CE4B5 for ; Fri, 4 Sep 2026 17:14:42 +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=1788542083; cv=none; b=ft3qjn0Aqj+Ro5muFK8wQKCy6Az+Gub44ZBaJ0BMGDbD0YtSa2AO1dE/zeD8BJWv7cwYWb+hL3vCP4fxuMgMEc4z96ob7omuESwfdT004so1Nq6ppkoOoRLafQa61v7/x+AfhWazIwg1gEBkaAqhrStuFrRkGFnsD3QIg/ELlvY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1788542083; c=relaxed/simple; bh=LHhOXV7VOxhazRFCl1Y+3Qd3joBBstTyE5/lOz4RDxI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=d6ktrWWn3LLwKkvzIdndn0IMHC0JeTF9+KXHWSyNQfRhVzpVnLgH6YDabZhYleLSGvM17rtMxe1S2IFKcO48oDIG12Ckh3rswtnvDn76zTO92vqzrgDuONmjUkBdXXWrjzscN1QzuR9H3ZUBpGZhHBFD2/2RORrp8tVEDrm7Gvs= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ZXP2Mmme; 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="ZXP2Mmme" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 507401F00A3D; Fri, 4 Sep 2026 17:14:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1788542082; bh=zaKiczivybvIujxaUzCX8rzMCVFDJAxYYw4bcElJDP0=; h=From:To:Cc:Subject:Date:Reply-To; b=ZXP2Mmme3Nmh8RnePavMvSPmeGQBZRyMzrs1g9MZgvMsj1e8WDix81AynIXgy/HwV IUz8ChDm4nPg+WiZSTaGxG8mq7comaGu73rqzCZz7Rx2fRgCB9+NalXQHz0m01agVE 1jfUF4B83Utre0C0iq/j3d8+kk2MAoF2TcfVlrnU= From: Greg Kroah-Hartman To: linux-cve-announce@vger.kernel.org Cc: Greg Kroah-Hartman Subject: CVE-2026-80892: erofs: cap LZMA stream pool size Date: Fri, 4 Sep 2026 19:09:33 +0200 Message-ID: <2026090429-CVE-2026-80892-e36d@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=3625; i=gregkh@linuxfoundation.org; h=from:subject:message-id; bh=7sDmbWs3CLEqusMCXQbk8WCTf1wUJQv6WF/cIWYIk1E=; b=owGbwMvMwCRo6H6F97bub03G02pJDFmzfnvVbJyR9vTtRsWuJYUtv443vdj+UCskJnj1TM/6h TwbvvQc64hlYRBkYpAVU2T5so3n6P6KQ4pehranYeawMoEMYeDiFICJ8PgzLGisWb9hvUzbG8mN c1ueXG57ebbhUAvDfDfx/TnlM0qdlxzxLud/zOsT8f/FbgA= 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: erofs: cap LZMA stream pool size fs/erofs/decompressor_lzma.c sizes the module-global MicroLZMA stream pool from num_possible_cpus() when the lzma_streams module parameter is unset, then z_erofs_load_lzma_config() preallocates one image-supplied dictionary per stream, accepting dictionaries up to 8 MiB. On high-CPU systems, a small EROFS image can pin hundreds of MiB of vmalloc-backed decoder state until the erofs module is unloaded. Impact: An EROFS image mounted by the system can pin up to 8 MiB of vmalloc memory per LZMA stream, either as intended or unexpectedly. Bound the default stream count by a new CONFIG_EROFS_FS_ZIP_LZMA_DEFAULT_MAX_STREAMS option, default 16, so the worst-case default preallocation is 128 MiB if the number of CPUs is no less than 16 while preserving the existing per-image dictionary limit. An explicit lzma_streams module parameter is still honoured as-is, so administrators who deliberately size the pool are not affected. The Linux kernel CVE team has assigned CVE-2026-80892 to this issue. Affected and fixed versions =========================== Issue introduced in 5.16 with commit 622ceaddb7649ca328832f50ba1400af778d75fa and fixed in 6.1.184 with commit 682cb3ece37fc5141e73bc726ccf4adb833e5189 Issue introduced in 5.16 with commit 622ceaddb7649ca328832f50ba1400af778d75fa and fixed in 6.6.151 with commit e8b3d09aa8889dda9be9cbb3d2f0218c4b9acde4 Issue introduced in 5.16 with commit 622ceaddb7649ca328832f50ba1400af778d75fa and fixed in 6.12.103 with commit 0c676903cb2a61992ded8e7907609cc6b0f11744 Issue introduced in 5.16 with commit 622ceaddb7649ca328832f50ba1400af778d75fa and fixed in 6.18.44 with commit 5aaa06dfc10f8398c8807453dbec738ea9af10e4 Issue introduced in 5.16 with commit 622ceaddb7649ca328832f50ba1400af778d75fa and fixed in 7.1.8 with commit e52da169b8c0d19bb2d803f2a07fe0e5a00462d6 Issue introduced in 5.16 with commit 622ceaddb7649ca328832f50ba1400af778d75fa and fixed in 7.2 with commit c9b47e6b23114e939b17f818471c7a46e59006e7 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-2026-80892 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/erofs/Kconfig fs/erofs/decompressor_lzma.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/682cb3ece37fc5141e73bc726ccf4adb833e5189 https://git.kernel.org/stable/c/e8b3d09aa8889dda9be9cbb3d2f0218c4b9acde4 https://git.kernel.org/stable/c/0c676903cb2a61992ded8e7907609cc6b0f11744 https://git.kernel.org/stable/c/5aaa06dfc10f8398c8807453dbec738ea9af10e4 https://git.kernel.org/stable/c/e52da169b8c0d19bb2d803f2a07fe0e5a00462d6 https://git.kernel.org/stable/c/c9b47e6b23114e939b17f818471c7a46e59006e7