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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_PASS,URIBL_BLOCKED,USER_AGENT_MUTT 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 96B35C43441 for ; Mon, 26 Nov 2018 23:25:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5EF0120C01 for ; Mon, 26 Nov 2018 23:25:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="gCMr4esE" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5EF0120C01 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727610AbeK0KVR (ORCPT ); Tue, 27 Nov 2018 05:21:17 -0500 Received: from mail.kernel.org ([198.145.29.99]:48906 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726448AbeK0KVR (ORCPT ); Tue, 27 Nov 2018 05:21:17 -0500 Received: from localhost (unknown [104.132.1.80]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B35F2208E4; Mon, 26 Nov 2018 23:25:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1543274730; bh=PF7iB6C2AhXKF3kqUaQXYATUPxfZ3B0YbXdWF+vWhwI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=gCMr4esE3ob7kG+XTxtzfP4BNWbUsJmnNuJFybjvyk9YwK6CSXxodlhVa+OuBNCTL 3Fhqor8TBrQYhUi9wQey0SrwAWe2rlg6eOcw+tLza1bbItiFE5FkfSMrsKom23jCZK aRcVHq5GE2dmtfMYrFmfRbgGekL9piwbQE0LkBzk= Date: Mon, 26 Nov 2018 15:25:29 -0800 From: Jaegeuk Kim To: Sheng Yong Cc: linux-kernel@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, "gongchen (E)" Subject: Re: [f2fs-dev] [PATCH] f2fs: check memory boundary by insane namelen Message-ID: <20181126232529.GC55960@jaegeuk-macbookpro.roam.corp.google.com> References: <20181115075040.83500-1-jaegeuk@kernel.org> <3d213d40-a4b0-6e60-87b2-81e66866ac4c@huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3d213d40-a4b0-6e60-87b2-81e66866ac4c@huawei.com> User-Agent: Mutt/1.8.2 (2017-04-18) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/23, Sheng Yong wrote: > Hi, Jaegeuk and Chao, > > On 2018/11/15 15:50, Jaegeuk Kim wrote: > > If namelen is corrupted to have very long value, fill_dentries can copy > > wrong memory area. > > > Is there any scenario that could hit this corruption? Or this is triggered > by fuzzing injection? Hi Sheng, It's from a fuzzing test. Thanks, > > thanks, > Sheng Yong > > > Signed-off-by: Jaegeuk Kim > > --- > > fs/f2fs/dir.c | 12 +++++++++++- > > 1 file changed, 11 insertions(+), 1 deletion(-) > > > > diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c > > index bacc667950b6..c0c845da12fa 100644 > > --- a/fs/f2fs/dir.c > > +++ b/fs/f2fs/dir.c > > @@ -808,6 +808,17 @@ int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, > > de_name.name = d->filename[bit_pos]; > > de_name.len = le16_to_cpu(de->name_len); > > + /* check memory boundary before moving forward */ > > + bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); > > + if (unlikely(bit_pos > d->max)) { > > + f2fs_msg(sbi->sb, KERN_WARNING, > > + "%s: corrupted namelen=%d, run fsck to fix.", > > + __func__, le16_to_cpu(de->name_len)); > > + set_sbi_flag(sbi, SBI_NEED_FSCK); > > + err = -EINVAL; > > + goto out; > > + } > > + > > if (f2fs_encrypted_inode(d->inode)) { > > int save_len = fstr->len; > > @@ -830,7 +841,6 @@ int f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, > > if (readdir_ra) > > f2fs_ra_node_page(sbi, le32_to_cpu(de->ino)); > > - bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); > > ctx->pos = start_pos + bit_pos; > > } > > out: > >