From nobody Tue Feb 10 10:04:21 2026 Delivered-To: importer@patchew.org Received-SPF: pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) client-ip=66.175.222.108; envelope-from=bounce+27952+99451+1787277+3901457@groups.io; helo=mail02.groups.io; Authentication-Results: mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+99451+1787277+3901457@groups.io; dmarc=fail(p=none dis=none) header.from=gmail.com ARC-Seal: i=1; a=rsa-sha256; t=1675333304; cv=none; d=zohomail.com; s=zohoarc; b=WGz4f40iQktV/Vcy0gFqByGAPyTx2wG1CkJXdXTualIzKeYWHGPIw67Lj7UPm1NdfGKcbgZVyCy0Y8YpgSWjkCW30gz6hNjCoEGn2kYaquvSR6j9M8V2nRr1XLmzFE6Mg95hwVuOjTPuc/0KcnWtAJ2TVQkQd7JjjFon5QjQgzo= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1675333304; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:Reply-To:References:Sender:Subject:To; bh=0ZIMk4RMhAbstdbtlaIF8DbjZHk7wQ2etaVLfX6Lido=; b=bkgWvZucwY8xOvAMOAzZP42/Xoo3KO145dGr5o6wThmhjLgJpuWorUPmwNJ92mee4BTZKKYj0G3z2JqEHr0+d7HgaY7fxPnUzAS1+ktXQ862GiXG/Q2HhlG0nVLVINVr9aVEtwZWr5DA9HHla9yYefG+FT0sJSUh4Hf5H+EUrB0= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass; spf=pass (zohomail.com: domain of groups.io designates 66.175.222.108 as permitted sender) smtp.mailfrom=bounce+27952+99451+1787277+3901457@groups.io; dmarc=fail header.from= (p=none dis=none) Received: from mail02.groups.io (mail02.groups.io [66.175.222.108]) by mx.zohomail.com with SMTPS id 1675333304844282.05017632105853; Thu, 2 Feb 2023 02:21:44 -0800 (PST) Return-Path: X-Received: by 127.0.0.2 with SMTP id RaTMYY1788612x2cS2AK8CYu; Thu, 02 Feb 2023 02:21:44 -0800 X-Received: from mail-ej1-f51.google.com (mail-ej1-f51.google.com [209.85.218.51]) by mx.groups.io with SMTP id smtpd.web11.11510.1675333303821052017 for ; Thu, 02 Feb 2023 02:21:44 -0800 X-Received: by mail-ej1-f51.google.com with SMTP id lu11so4594031ejb.3 for ; Thu, 02 Feb 2023 02:21:43 -0800 (PST) X-Gm-Message-State: pqXIX8uaCcjcO5t2GlpjuXIbx1787277AA= X-Google-Smtp-Source: AK7set+VsmaYLx3gnMXHOozmbc90+OU0ha20K8XoNsoVIVH2HZYJQS58dBV0qj0AO9n+9kbM8zMbdw== X-Received: by 2002:a17:906:b4b:b0:878:71fe:2f12 with SMTP id v11-20020a1709060b4b00b0087871fe2f12mr6334582ejg.50.1675333302240; Thu, 02 Feb 2023 02:21:42 -0800 (PST) X-Received: from localhost.localdomain ([176.62.67.29]) by smtp.gmail.com with ESMTPSA id ci22-20020a170906c35600b0087bcda2b07bsm10013121ejb.202.2023.02.02.02.21.41 (version=TLS1_3 cipher=TLS_CHACHA20_POLY1305_SHA256 bits=256/256); Thu, 02 Feb 2023 02:21:42 -0800 (PST) From: "Savva Mitrofanov" To: devel@edk2.groups.io Cc: =?UTF-8?q?Marvin=20H=C3=A4user?= , Pedro Falcato , Vitaly Cheptsov Subject: [edk2-devel] [edk2-platforms][PATCH v4 05/12] Ext4Pkg: Fix shift out of bounds in Ext4OpenSuperblock Date: Thu, 2 Feb 2023 16:21:26 +0600 Message-Id: <20230202102133.51606-6-savvamtr@gmail.com> In-Reply-To: <20230202102133.51606-1-savvamtr@gmail.com> References: <20230202102133.51606-1-savvamtr@gmail.com> MIME-Version: 1.0 Precedence: Bulk List-Unsubscribe: List-Subscribe: List-Help: Sender: devel@edk2.groups.io List-Id: Mailing-List: list devel@edk2.groups.io; contact devel+owner@edk2.groups.io Reply-To: devel@edk2.groups.io,savvamtr@gmail.com Content-Transfer-Encoding: quoted-printable DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=groups.io; q=dns/txt; s=20140610; t=1675333304; bh=bE1frtnWBQu3zkAshU4tAgU8P7iYXIzWuuu8epgXZPo=; h=Cc:Content-Type:Date:From:Reply-To:Subject:To; b=Db74C1N9glj+c3Lp0lIcAVzlFf3ViustFQldBMMtOiTK+ofdHR1gVPD+34wpgouwmPj kKwB+lm6L6IbuLAFwrtz/tf6OYK1SJ5rClnT2MP+LMp370AiR5hYqegbCVmrgxlCcJTLE /6mOOvvWN2RvWuudIlzpMth4JSgV4c8sIfg= X-ZohoMail-DKIM: pass (identity @groups.io) X-ZM-MESSAGEID: 1675333305257100017 Content-Type: text/plain; charset="utf-8" Missing check for wrong s_log_block_size exponent leads to shift out of bounds. Limit block size to 2 MiB Cc: Marvin H=C3=A4user Cc: Pedro Falcato Cc: Vitaly Cheptsov Fixes: d9ceedca6c8f ("Ext4Pkg: Add Ext4Dxe driver.") Signed-off-by: Savva Mitrofanov Reviewed-by: Pedro Falcato Reviewed-by: Marvin H=C3=A4user --- Features/Ext4Pkg/Ext4Dxe/Ext4Dxe.h | 14 ++++++++++++++ Features/Ext4Pkg/Ext4Dxe/Superblock.c | 5 +++++ 2 files changed, 19 insertions(+) diff --git a/Features/Ext4Pkg/Ext4Dxe/Ext4Dxe.h b/Features/Ext4Pkg/Ext4Dxe/= Ext4Dxe.h index c977a97ca5c2..d3f72a98d7f8 100644 --- a/Features/Ext4Pkg/Ext4Dxe/Ext4Dxe.h +++ b/Features/Ext4Pkg/Ext4Dxe/Ext4Dxe.h @@ -40,6 +40,20 @@ #define EXT4_EFI_PATH_MAX 4096 #define EXT4_DRIVER_VERSION 0x0000 =20 +// +// The EXT4 Specification doesn't strictly limit block size and this value= could be up to 2^31, +// but in practice it is limited by PAGE_SIZE due to performance significa= nt impact. +// Many EXT4 implementations have size of block limited to PAGE_SIZE. In m= any cases it's limited +// to 4096, which is a commonly supported page size on most MMU-capable ha= rdware, and up to 65536. +// So, to take a balance between compatibility and security measures, it i= s decided to use the +// value of 2MiB as the limit, which is equal to large page size on new ha= rdware. +// As for supporting big block sizes, EXT4 has a RO_COMPAT_FEATURE called = BIGALLOC, which changes +// EXT4 to use clustered allocation, so that each bit in the ext4 block al= location bitmap addresses +// a power of two number of blocks. So it would be wiser to implement and = use this feature +// if there is such a need instead of big block size. +// +#define EXT4_LOG_BLOCK_SIZE_MAX 11 + /** Opens an ext4 partition and installs the Simple File System protocol. =20 diff --git a/Features/Ext4Pkg/Ext4Dxe/Superblock.c b/Features/Ext4Pkg/Ext4D= xe/Superblock.c index be3527e4d618..3f56de93c105 100644 --- a/Features/Ext4Pkg/Ext4Dxe/Superblock.c +++ b/Features/Ext4Pkg/Ext4Dxe/Superblock.c @@ -248,6 +248,11 @@ Ext4OpenSuperblock ( return EFI_VOLUME_CORRUPTED; } =20 + if (Sb->s_log_block_size > EXT4_LOG_BLOCK_SIZE_MAX) { + DEBUG ((DEBUG_ERROR, "[ext4] SuperBlock s_log_block_size %lu is too bi= g\n", Sb->s_log_block_size)); + return EFI_UNSUPPORTED; + } + Partition->BlockSize =3D (UINT32)LShiftU64 (1024, Sb->s_log_block_size); =20 // The size of a block group can also be calculated as 8 * Partition->Bl= ockSize --=20 2.39.1 -=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D-=3D- Groups.io Links: You receive all messages sent to this group. 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