From patchwork Mon Jul 12 06:02:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 474122 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1F47AC11F69 for ; Mon, 12 Jul 2021 06:55:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0C18E61380 for ; Mon, 12 Jul 2021 06:55:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239917AbhGLG6d (ORCPT ); Mon, 12 Jul 2021 02:58:33 -0400 Received: from mail.kernel.org ([198.145.29.99]:58140 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239307AbhGLG5c (ORCPT ); Mon, 12 Jul 2021 02:57:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 45D4F61248; Mon, 12 Jul 2021 06:54:36 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1626072876; bh=DwHXodav4ShwyZ/zm5t4mBkvd/xVCgOhbEi9L4KjvmU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FxsMMJux5wLdrK6WZUTiAg6hZt5YoVgFPT+v08K4IDmuID0EMFOvcgTS4jqCh0s4Y U1GkBjOcqFJCYj+ty0qzFFiIyzLur86WAI3aSqWaMp/kW8cc3mitUsaKliG7gtt2kG yQawCYjNKQiRD5V20sUjuo4ByO6MMFwiMVFr/x0Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, stable@kernel.org, Jan Kara , Theodore Tso Subject: [PATCH 5.12 051/700] ext4: fix overflow in ext4_iomap_alloc() Date: Mon, 12 Jul 2021 08:02:14 +0200 Message-Id: <20210712060931.899255522@linuxfoundation.org> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20210712060924.797321836@linuxfoundation.org> References: <20210712060924.797321836@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jan Kara commit d0b040f5f2557b2f507c01e88ad8cff424fdc6a9 upstream. A code in iomap alloc may overflow block number when converting it to byte offset. Luckily this is mostly harmless as we will just use more expensive method of writing using unwritten extents even though we are writing beyond i_size. Cc: stable@kernel.org Fixes: 378f32bab371 ("ext4: introduce direct I/O write using iomap infrastructure") Signed-off-by: Jan Kara Link: https://lore.kernel.org/r/20210412102333.2676-4-jack@suse.cz Signed-off-by: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman --- fs/ext4/inode.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/fs/ext4/inode.c +++ b/fs/ext4/inode.c @@ -3420,7 +3420,7 @@ retry: * i_disksize out to i_size. This could be beyond where direct I/O is * happening and thus expose allocated blocks to direct I/O reads. */ - else if ((map->m_lblk * (1 << blkbits)) >= i_size_read(inode)) + else if (((loff_t)map->m_lblk << blkbits) >= i_size_read(inode)) m_flags = EXT4_GET_BLOCKS_CREATE; else if (ext4_test_inode_flag(inode, EXT4_INODE_EXTENTS)) m_flags = EXT4_GET_BLOCKS_IO_CREATE_EXT;