From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 50494C77B7F for ; Mon, 8 May 2023 11:33:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236015AbjEHLdn (ORCPT ); Mon, 8 May 2023 07:33:43 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52342 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235969AbjEHLdT (ORCPT ); Mon, 8 May 2023 07:33:19 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 92BBF3DC87 for ; Mon, 8 May 2023 04:32:38 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id E984F63126 for ; Mon, 8 May 2023 11:32:17 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 06C92C433D2; Mon, 8 May 2023 11:32:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1683545537; bh=eIk3xdqU0k0QdvUrF+fEPkdyjl1lCi1xcasx3ZARBgA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=m+7TLAJlUXUNI0COfvqN8tefnxshHsELhP1FY2rN5Vsx6XYGL/hUPlwrKXxM6NA9t U4FO/91t7Dpu5cZy4Cg+H6KpgHMm/KK44Jmm658Z8F4QJ4sXHm3MaHqSL6bgP94+SI HA2InCVRYd+F+C3VKFCGfWhb8M0x/qLhmPQPdvuE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Gao Xiang , Chao Yu , Sasha Levin , syzbot+aafb3f37cfeb6534c4ac@syzkaller.appspotmail.com Subject: [PATCH 5.15 073/371] erofs: stop parsing non-compact HEAD index if clusterofs is invalid Date: Mon, 8 May 2023 11:44:34 +0200 Message-Id: <20230508094815.014058453@linuxfoundation.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230508094811.912279944@linuxfoundation.org> References: <20230508094811.912279944@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Gao Xiang [ Upstream commit cc4efd3dd2ac9f89143e5d881609747ecff04164 ] Syzbot generated a crafted image [1] with a non-compact HEAD index of clusterofs 33024 while valid numbers should be 0 ~ lclustersize-1, which causes the following unexpected behavior as below: BUG: unable to handle page fault for address: fffff52101a3fff9 #PF: supervisor read access in kernel mode #PF: error_code(0x0000) - not-present page PGD 23ffed067 P4D 23ffed067 PUD 0 Oops: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 4398 Comm: kworker/u5:1 Not tainted 6.3.0-rc6-syzkaller-g09a9639e56c0 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/30/2023 Workqueue: erofs_worker z_erofs_decompressqueue_work RIP: 0010:z_erofs_decompress_queue+0xb7e/0x2b40 ... Call Trace: z_erofs_decompressqueue_work+0x99/0xe0 process_one_work+0x8f6/0x1170 worker_thread+0xa63/0x1210 kthread+0x270/0x300 ret_from_fork+0x1f/0x30 Note that normal images or images using compact indexes are not impacted. Let's fix this now. [1] https://lore.kernel.org/r/000000000000ec75b005ee97fbaa@google.com Reported-and-tested-by: syzbot+aafb3f37cfeb6534c4ac@syzkaller.appspotmail.com Fixes: 02827e1796b3 ("staging: erofs: add erofs_map_blocks_iter") Fixes: 152a333a5895 ("staging: erofs: add compacted compression indexes support") Signed-off-by: Gao Xiang Reviewed-by: Chao Yu Link: https://lore.kernel.org/r/20230410173714.104604-1-hsiangkao@linux.alibaba.com Signed-off-by: Sasha Levin --- fs/erofs/zmap.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c index 73b86b5c1a75b..2c8575a8f6dae 100644 --- a/fs/erofs/zmap.c +++ b/fs/erofs/zmap.c @@ -191,6 +191,10 @@ static int legacy_load_cluster_from_disk(struct z_erofs_maprecorder *m, case Z_EROFS_VLE_CLUSTER_TYPE_PLAIN: case Z_EROFS_VLE_CLUSTER_TYPE_HEAD: m->clusterofs = le16_to_cpu(di->di_clusterofs); + if (m->clusterofs >= 1 << vi->z_logical_clusterbits) { + DBG_BUGON(1); + return -EFSCORRUPTED; + } m->pblk = le32_to_cpu(di->di_u.blkaddr); break; default: -- 2.39.2