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 X-Spam-Level: X-Spam-Status: No, score=-14.3 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 A64E6C4363D for ; Fri, 25 Sep 2020 15:20:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 60650208B6 for ; Fri, 25 Sep 2020 15:20:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601047225; bh=Rgt+BCsL/KkkjWh67h04RmRvHL8oKTtmyN9/5r6atMk=; h=From:To:Cc:Subject:Date:List-ID:From; b=aTyZWkrdBhgW9yeXtjiOUxfSNxD2x8XUrJRZrWmyiwR7CejNglJIBGJuuPrfJyHGJ bu8JqCIIhWLLRMaUbAzVn8RyBrzb1AErTiip8FaZSGrU4CTgVxpW757IPusYVLO2HS y+8oDn/ZNzZDjMQMTIFKMj5ZtllbBMt1LDeq8bbg= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729193AbgIYPUY (ORCPT ); Fri, 25 Sep 2020 11:20:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:53214 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729002AbgIYPUY (ORCPT ); Fri, 25 Sep 2020 11:20:24 -0400 Received: from localhost.localdomain (unknown [49.65.245.23]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A2E6920878; Fri, 25 Sep 2020 15:20:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601047223; bh=Rgt+BCsL/KkkjWh67h04RmRvHL8oKTtmyN9/5r6atMk=; h=From:To:Cc:Subject:Date:From; b=hOqrxJj5Obzg0ZU5+txEcT2yZGWeyxDoFafMpLkO/+iVH/m/IbE/2M3lZILid/53J BWbwFDldm3t5e/aaZSbZIeu2I7P8GOLbAV0aWhNPmSvWMKgU805cQVWRsxGVnfyWtZ 3BhyuV0yDCkdig6njBZJlWvFQAuZ2nkGgB4yMsWo= From: Chao Yu To: jaegeuk@kernel.org Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, Chao Yu Subject: [PATCH] f2fs: fix uninit-value in f2fs_lookup Date: Fri, 25 Sep 2020 23:19:26 +0800 Message-Id: <20200925151926.2658-1-chao@kernel.org> X-Mailer: git-send-email 2.22.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chao Yu As syzbot reported: Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x21c/0x280 lib/dump_stack.c:118 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:122 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:219 f2fs_lookup+0xe05/0x1a80 fs/f2fs/namei.c:503 lookup_open fs/namei.c:3082 [inline] open_last_lookups fs/namei.c:3177 [inline] path_openat+0x2729/0x6a90 fs/namei.c:3365 do_filp_open+0x2b8/0x710 fs/namei.c:3395 do_sys_openat2+0xa88/0x1140 fs/open.c:1168 do_sys_open fs/open.c:1184 [inline] __do_compat_sys_openat fs/open.c:1242 [inline] __se_compat_sys_openat+0x2a4/0x310 fs/open.c:1240 __ia32_compat_sys_openat+0x56/0x70 fs/open.c:1240 do_syscall_32_irqs_on arch/x86/entry/common.c:80 [inline] __do_fast_syscall_32+0x129/0x180 arch/x86/entry/common.c:139 do_fast_syscall_32+0x6a/0xc0 arch/x86/entry/common.c:162 do_SYSENTER_32+0x73/0x90 arch/x86/entry/common.c:205 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c In f2fs_lookup(), @res_page could be used before being initialized, because in __f2fs_find_entry(), once F2FS_I(dir)->i_current_depth was been fuzzed to zero, then @res_page will never be initialized, causing this kmsan warning, relocating @res_page initialization place to fix this bug. Signed-off-by: Chao Yu --- fs/f2fs/dir.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-) diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c index 703cf8e21fc0..83630341ffa3 100644 --- a/fs/f2fs/dir.c +++ b/fs/f2fs/dir.c @@ -357,16 +357,15 @@ struct f2fs_dir_entry *__f2fs_find_entry(struct inode *dir, unsigned int max_depth; unsigned int level; + *res_page = NULL; + if (f2fs_has_inline_dentry(dir)) { - *res_page = NULL; de = f2fs_find_in_inline_dir(dir, fname, res_page); goto out; } - if (npages == 0) { - *res_page = NULL; + if (npages == 0) goto out; - } max_depth = F2FS_I(dir)->i_current_depth; if (unlikely(max_depth > MAX_DIR_HASH_DEPTH)) { -- 2.22.0