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 E9FBBC6FA82 for ; Mon, 12 Sep 2022 15:38:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229630AbiILPiE (ORCPT ); Mon, 12 Sep 2022 11:38:04 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36852 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229568AbiILPiC (ORCPT ); Mon, 12 Sep 2022 11:38:02 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A22082DABE; Mon, 12 Sep 2022 08:38:01 -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 46B6061248; Mon, 12 Sep 2022 15:38:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 7A234C433D6; Mon, 12 Sep 2022 15:38:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1662997080; bh=oxqqC71whU82K+lMvDngYtKvu3gWEOvauoFnwRSlPuI=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=q6FnABTA5i4SLOkkHKAXSp6F7n8kO/2lwpfNaB/0kXGFyYWEq7OVQt4anSllmoc9A LnxmTDok5aY+mdK+LaovQaRACzxyahDDplVCpWqBYSm8pHozW1TgLfTg8nT2G9r2H/ PG3VbZU2PIGx5VyUSi8iiaVjvGa1cEqyfOq1cQ+mKaYASiXPT7gM+4PM2GdbSSZ93T b0irWRDf8HkXgv9gvE+3qmvmpLmFcnH276eajOE60W8SuLQ3ckB0uDMVE3cpgttcfn 0Ls63zOTnuSABq0VYuw/2prRE5ejjmmgkeh6lMyyg0VWhOImTwJRnmgjJQiRoCsqKP +w/QWGhyWAOlg== Date: Mon, 12 Sep 2022 08:37:58 -0700 From: Jaegeuk Kim To: Chao Yu Cc: linux-f2fs-devel@lists.sourceforge.net, linux-kernel@vger.kernel.org, stable@vger.kernel.org, syzbot+775a3440817f74fddb8c@syzkaller.appspotmail.com Subject: Re: [PATCH] f2fs: fix to detect obsolete inner inode during fill_super() Message-ID: References: <20220908105334.98572-1-chao@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20220908105334.98572-1-chao@kernel.org> Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org On 09/08, Chao Yu wrote: > Sometimes we can get a cached meta_inode which has no aops yet. Let's set it > all the time to fix the below panic. > > Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 > Mem abort info: > ESR = 0x0000000086000004 > EC = 0x21: IABT (current EL), IL = 32 bits > SET = 0, FnV = 0 > EA = 0, S1PTW = 0 > FSC = 0x04: level 0 translation fault > user pgtable: 4k pages, 48-bit VAs, pgdp=0000000109ee4000 > [0000000000000000] pgd=0000000000000000, p4d=0000000000000000 > Internal error: Oops: 86000004 [#1] PREEMPT SMP > Modules linked in: > CPU: 1 PID: 3045 Comm: syz-executor330 Not tainted 6.0.0-rc2-syzkaller-16455-ga41a877bc12d #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 > pstate: 80400005 (Nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) > pc : 0x0 > lr : folio_mark_dirty+0xbc/0x208 mm/page-writeback.c:2748 > sp : ffff800012783970 > x29: ffff800012783970 x28: 0000000000000000 x27: ffff800012783b08 > x26: 0000000000000001 x25: 0000000000000400 x24: 0000000000000001 > x23: ffff0000c736e000 x22: 0000000000000045 x21: 05ffc00000000015 > x20: ffff0000ca7403b8 x19: fffffc00032ec600 x18: 0000000000000181 > x17: ffff80000c04d6bc x16: ffff80000dbb8658 x15: 0000000000000000 > x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000000 > x11: ff808000083e9814 x10: 0000000000000000 x9 : ffff8000083e9814 > x8 : 0000000000000000 x7 : 0000000000000000 x6 : 0000000000000000 > x5 : ffff0000cbb19000 x4 : ffff0000cb3d2000 x3 : ffff0000cbb18f80 > x2 : fffffffffffffff0 x1 : fffffc00032ec600 x0 : ffff0000ca7403b8 > Call trace: > 0x0 > set_page_dirty+0x38/0xbc mm/folio-compat.c:62 > f2fs_update_meta_page+0x80/0xa8 fs/f2fs/segment.c:2369 > do_checkpoint+0x794/0xea8 fs/f2fs/checkpoint.c:1522 > f2fs_write_checkpoint+0x3b8/0x568 fs/f2fs/checkpoint.c:1679 > > The root cause is, quoted from Jaegeuk: > > It turned out there is a bug in reiserfs which doesn't free the root > inode (ino=2). That leads f2fs to find an ino=2 with the previous > superblock point used by reiserfs. That stale inode has no valid > mapping that f2fs can use, result in kernel panic. > > This patch adds sanity check in f2fs_iget() to avoid finding stale > inode during inner inode initialization. > > Cc: stable@vger.kernel.org > Reported-by: syzbot+775a3440817f74fddb8c@syzkaller.appspotmail.com > Signed-off-by: Jaegeuk Kim > Signed-off-by: Chao Yu > --- > fs/f2fs/inode.c | 11 +++++++++++ > 1 file changed, 11 insertions(+) > > diff --git a/fs/f2fs/inode.c b/fs/f2fs/inode.c > index ccb29034af59..df1a82fbfaf2 100644 > --- a/fs/f2fs/inode.c > +++ b/fs/f2fs/inode.c > @@ -493,6 +493,17 @@ struct inode *f2fs_iget_inner(struct super_block *sb, unsigned long ino) > struct inode *inode; > int ret = 0; > > + if (ino == F2FS_NODE_INO(sbi) || ino == F2FS_META_INO(sbi) || > + ino == F2FS_COMPRESS_INO(sbi)) { > + inode = ilookup(sb, ino); > + if (inode) { > + iput(inode); > + f2fs_err(sbi, "there is obsoleted inner inode %lu cached in hash table", > + ino); > + return ERR_PTR(-EFSCORRUPTED); Well, this does not indicate f2fs is corrupted. I'd rather expect to fix reiserfs instead of f2fs workaround which hides the bug. > + } > + } > + > inode = iget_locked(sb, ino); > if (!inode) > return ERR_PTR(-ENOMEM); > -- > 2.25.1