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 0DD9C41F37E; Thu, 16 Jul 2026 14:14:59 +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=1784211300; cv=none; b=kIDXb855lK0olirlD9CPTOwcwV2IoHocUjD/kVKWmEeM2IXubnjdlqk6kUOOAkXPdwhYQiIqra0NXllbLCDZMD86EFsjI/iRj6i+vQ52gwx3IMwSjlbKiNN/yIR20gKp7JC7GSCOKvFUpdybD7qVldag+Z7FsyyRXqfH0lmuw5s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784211300; c=relaxed/simple; bh=CrVmpQ68d1595JPTzWDbb0glpMc/5LQmd/dy6pM6Ndg=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ODTIgD48ZodUAkC4Ymuqn5hzScpweWxYvFEm65TCBr9VSY2yLw4l/L5o2m958Lx870+kpYDrT77+f8DJPZijXfBoHf5YRojuq6VeWcB+OEd1GfF+gVfvjr1tV+ocosP8H0U00UA7WdvJ0JOaSJGvg+irmLQ66Q63o6H5GIK8FsA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=ivJdcaLu; 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="ivJdcaLu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 728FE1F000E9; Thu, 16 Jul 2026 14:14:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784211298; bh=csX1SUxIEgduYzxjDhXZhDoeRTOWMn69uchJPIgxyGM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=ivJdcaLuFI/CnkccXpj+uvS4R/GHTb+CqHWcJi62jXDNQDTvS991K2BwjYCUZnxSN qi376daITxBxkfHbDjgLgdIqO4YuxViQGZaC2wXruyrgM7xAzH83vs5VSTrhEv6PBf DL3U00xQVpKPINgj6aBhvFf6ZNbvE4QDzr+fFjuU= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Bryam Vargas , Jan Kara Subject: [PATCH 6.18 332/480] udf: validate VAT header length against the VAT inode size Date: Thu, 16 Jul 2026 15:31:19 +0200 Message-ID: <20260716133051.996649093@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260716133044.672218725@linuxfoundation.org> References: <20260716133044.672218725@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Bryam Vargas commit d8202786b3d75125c84ebc4de6d946f92fde0ee8 upstream. udf_load_vat() takes the virtual partition's start offset straight from the on-disk VAT 2.0 header without checking it against the VAT inode size: map->s_type_specific.s_virtual.s_start_offset = le16_to_cpu(vat20->lengthHeader); map->s_type_specific.s_virtual.s_num_entries = (sbi->s_vat_inode->i_size - map->s_type_specific.s_virtual.s_start_offset) >> 2; lengthHeader is a fully attacker-controlled 16-bit value. If it exceeds the VAT inode size, the s_num_entries subtraction underflows to a huge count, which defeats the "block > s_num_entries" bound in udf_get_pblock_virt15(); and on the ICB-inline path that function reads ((__le32 *)(iinfo->i_data + s_start_offset))[block] so a large s_start_offset indexes past the inode's in-ICB data. Mounting a crafted UDF image with a virtual (VAT) partition then triggers an out-of-bounds read. Reject a VAT whose header length does not leave room for at least one entry within the VAT inode. Fixes: fa5e08156335 ("udf: Handle VAT packed inside inode properly") Cc: stable@vger.kernel.org Signed-off-by: Bryam Vargas Link: https://patch.msgid.link/20260612-b4-disp-9a2317ee-v1-1-fefef5736154@proton.me Signed-off-by: Jan Kara Signed-off-by: Greg Kroah-Hartman --- fs/udf/super.c | 8 ++++++++ 1 file changed, 8 insertions(+) --- a/fs/udf/super.c +++ b/fs/udf/super.c @@ -1263,6 +1263,14 @@ static int udf_load_vat(struct super_blo map->s_type_specific.s_virtual.s_start_offset = le16_to_cpu(vat20->lengthHeader); + if (map->s_type_specific.s_virtual.s_start_offset + > sbi->s_vat_inode->i_size) { + udf_err(sb, "Corrupted VAT header length %u (VAT inode size %lld)\n", + map->s_type_specific.s_virtual.s_start_offset, + sbi->s_vat_inode->i_size); + brelse(bh); + return -EFSCORRUPTED; + } map->s_type_specific.s_virtual.s_num_entries = (sbi->s_vat_inode->i_size - map->s_type_specific.s_virtual.