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=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 autolearn=unavailable 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 1573BC55178 for ; Sat, 31 Oct 2020 20:04:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D1350206F9 for ; Sat, 31 Oct 2020 20:04:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604174698; bh=FyVEfoAcUcTxrvhSxANkxkD7tnNZuVOiijmKvVEGQns=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=Qn5BaRdGRPREQjab5WFjKxRnV3iv4X329PhFDK6umPLhBgPlSWv0k75q3OwqSVQEg N2kOG8N4CV7Y9A4xUi/ig4GIttup4AhokQo06x2mzF4P9oqaHLCnJzN9GaCNTwTa+C wSvpOeeTV//X9D10hWcKN14YFowPv0GxCNeiH5ck= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728536AbgJaUE5 (ORCPT ); Sat, 31 Oct 2020 16:04:57 -0400 Received: from mail.kernel.org ([198.145.29.99]:32898 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728451AbgJaUE4 (ORCPT ); Sat, 31 Oct 2020 16:04:56 -0400 Received: from sol.localdomain (172-10-235-113.lightspeed.sntcca.sbcglobal.net [172.10.235.113]) (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 53DE9206F7; Sat, 31 Oct 2020 20:04:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604174696; bh=FyVEfoAcUcTxrvhSxANkxkD7tnNZuVOiijmKvVEGQns=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=GhLQnNsKwQLpyTPHhEfFMobk2XL2bL2fndIljpa1SRIaBCxCdQAXciCHfvV6UZXE5 fkZMAFvCWFcO0eh9/gUr/AybzB+ZHYKNSsQYSBjDwpB9pXfI3zlpTpQSWEJNJ1kfKb 3uHf52vN0oJqxvQfgdOzmRLEhs8Ofb3kFWRihkDM= Date: Sat, 31 Oct 2020 13:04:54 -0700 From: Eric Biggers To: Greg Kroah-Hartman Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, Chao Yu , Jaegeuk Kim , Sasha Levin Subject: Re: [PATCH 4.4 010/149] f2fs: check memory boundary by insane namelen Message-ID: <20201031200454.GB936@sol.localdomain> References: <20200820092125.688850368@linuxfoundation.org> <20200820092126.196020416@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200820092126.196020416@linuxfoundation.org> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Aug 20, 2020 at 11:21:27AM +0200, Greg Kroah-Hartman wrote: > From: Jaegeuk Kim > > [ Upstream commit 4e240d1bab1ead280ddf5eb05058dba6bbd57d10 ] > > If namelen is corrupted to have very long value, fill_dentries can copy > wrong memory area. > > Reviewed-by: Chao Yu > Signed-off-by: Jaegeuk Kim > Signed-off-by: Sasha Levin > --- > fs/f2fs/dir.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c > index 92a240616f520..5411d6667781f 100644 > --- a/fs/f2fs/dir.c > +++ b/fs/f2fs/dir.c > @@ -805,6 +805,16 @@ bool 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(F2FS_I_SB(d->inode)->sb, KERN_WARNING, > + "%s: corrupted namelen=%d, run fsck to fix.", > + __func__, le16_to_cpu(de->name_len)); > + set_sbi_flag(F2FS_I_SB(d->inode)->sb->s_fs_info, SBI_NEED_FSCK); > + return -EINVAL; > + } > + > if (f2fs_encrypted_inode(d->inode)) { > int save_len = fstr->len; > int ret; > @@ -829,7 +839,6 @@ bool f2fs_fill_dentries(struct dir_context *ctx, struct f2fs_dentry_ptr *d, > le32_to_cpu(de->ino), d_type)) > return true; > > - bit_pos += GET_DENTRY_SLOTS(le16_to_cpu(de->name_len)); > ctx->pos = start_pos + bit_pos; This buggy backport broke f2fs encryption in 4.4-stable, due to a missing prerequisite commit (https://lkml.kernel.org/stable/20201031195809.377983-1-ebiggers@kernel.org/). Why didn't this backport get Cc'ed to the subsystem mailing list? It wasn't even a clean cherry pick. - Eric