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=-12.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 65CA6C388F9 for ; Tue, 3 Nov 2020 20:41:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1DEDA22277 for ; Tue, 3 Nov 2020 20:41:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436074; bh=wX4d7FN/inLk35NEUKxXJVXUNXsCHQUkglhjOTDNNjo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=V0Bn09eNVBYVLOB1TR80c/KK2KTGGAi4KGVd6Am2fBxQ5d+L3kU+8bw4ebxdVLQ3P s9DzSh1gvin+0fgfTlWCEGC0WLAlWrXWFIghIqJ/0MuCCHzMUhcvGA/EGPmZlFVZOk Vtt8r3OAvUUnfIwKq7BaA1S8i9rAbTU4b3yNqa4I= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730324AbgKCUlM (ORCPT ); Tue, 3 Nov 2020 15:41:12 -0500 Received: from mail.kernel.org ([198.145.29.99]:52654 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729897AbgKCUlC (ORCPT ); Tue, 3 Nov 2020 15:41:02 -0500 Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) (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 05AE922226; Tue, 3 Nov 2020 20:41:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1604436061; bh=wX4d7FN/inLk35NEUKxXJVXUNXsCHQUkglhjOTDNNjo=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=KDcr+YC4nHjQamg8KP67yB4NinKhwH2G0bIt0d7xMnxLf4Yxhmvzdc18V+tenmeQH CtxvAMowWX8NSZFfNe27gwUbkJHIHaY6vMwZEFj0Q9Hr9Wf+I6+PqOEIgSM7J9Kmls 9diAbBPMANGOkWnekJ+NkgyuqLvIk2XDrioqfgE8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, syzbot+ee250ac8137be41d7b13@syzkaller.appspotmail.com, Chao Yu , Jaegeuk Kim , Sasha Levin Subject: [PATCH 5.9 059/391] f2fs: handle errors of f2fs_get_meta_page_nofail Date: Tue, 3 Nov 2020 21:31:50 +0100 Message-Id: <20201103203351.373316808@linuxfoundation.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20201103203348.153465465@linuxfoundation.org> References: <20201103203348.153465465@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jaegeuk Kim [ Upstream commit 86f33603f8c51537265ff7ac0320638fd2cbdb1b ] First problem is we hit BUG_ON() in f2fs_get_sum_page given EIO on f2fs_get_meta_page_nofail(). Quick fix was not to give any error with infinite loop, but syzbot caught a case where it goes to that loop from fuzzed image. In turned out we abused f2fs_get_meta_page_nofail() like in the below call stack. - f2fs_fill_super - f2fs_build_segment_manager - build_sit_entries - get_current_sit_page INFO: task syz-executor178:6870 can't die for more than 143 seconds. task:syz-executor178 state:R stack:26960 pid: 6870 ppid: 6869 flags:0x00004006 Call Trace: Showing all locks held in the system: 1 lock held by khungtaskd/1179: #0: ffffffff8a554da0 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:6242 1 lock held by systemd-journal/3920: 1 lock held by in:imklog/6769: #0: ffff88809eebc130 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930 1 lock held by syz-executor178/6870: #0: ffff8880925120e0 (&type->s_umount_key#47/1){+.+.}-{3:3}, at: alloc_super+0x201/0xaf0 fs/super.c:229 Actually, we didn't have to use _nofail in this case, since we could return error to mount(2) already with the error handler. As a result, this patch tries to 1) remove _nofail callers as much as possible, 2) deal with error case in last remaining caller, f2fs_get_sum_page(). Reported-by: syzbot+ee250ac8137be41d7b13@syzkaller.appspotmail.com Reviewed-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/checkpoint.c | 2 +- fs/f2fs/f2fs.h | 2 +- fs/f2fs/node.c | 2 +- fs/f2fs/segment.c | 12 +++++++++--- 4 files changed, 12 insertions(+), 6 deletions(-) diff --git a/fs/f2fs/checkpoint.c b/fs/f2fs/checkpoint.c index 0b7aec059f112..4a97fe4ddf789 100644 --- a/fs/f2fs/checkpoint.c +++ b/fs/f2fs/checkpoint.c @@ -107,7 +107,7 @@ struct page *f2fs_get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index) return __get_meta_page(sbi, index, true); } -struct page *f2fs_get_meta_page_nofail(struct f2fs_sb_info *sbi, pgoff_t index) +struct page *f2fs_get_meta_page_retry(struct f2fs_sb_info *sbi, pgoff_t index) { struct page *page; int count = 0; diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 98c4b166f192b..d44c6c36de678 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -3385,7 +3385,7 @@ enum rw_hint f2fs_io_type_to_rw_hint(struct f2fs_sb_info *sbi, void f2fs_stop_checkpoint(struct f2fs_sb_info *sbi, bool end_io); struct page *f2fs_grab_meta_page(struct f2fs_sb_info *sbi, pgoff_t index); struct page *f2fs_get_meta_page(struct f2fs_sb_info *sbi, pgoff_t index); -struct page *f2fs_get_meta_page_nofail(struct f2fs_sb_info *sbi, pgoff_t index); +struct page *f2fs_get_meta_page_retry(struct f2fs_sb_info *sbi, pgoff_t index); struct page *f2fs_get_tmp_page(struct f2fs_sb_info *sbi, pgoff_t index); bool f2fs_is_valid_blkaddr(struct f2fs_sb_info *sbi, block_t blkaddr, int type); diff --git a/fs/f2fs/node.c b/fs/f2fs/node.c index cb1b5b61a1dab..cc4700f6240db 100644 --- a/fs/f2fs/node.c +++ b/fs/f2fs/node.c @@ -109,7 +109,7 @@ static void clear_node_page_dirty(struct page *page) static struct page *get_current_nat_page(struct f2fs_sb_info *sbi, nid_t nid) { - return f2fs_get_meta_page_nofail(sbi, current_nat_addr(sbi, nid)); + return f2fs_get_meta_page(sbi, current_nat_addr(sbi, nid)); } static struct page *get_next_nat_page(struct f2fs_sb_info *sbi, nid_t nid) diff --git a/fs/f2fs/segment.c b/fs/f2fs/segment.c index e247a5ef3713f..2628406f43f64 100644 --- a/fs/f2fs/segment.c +++ b/fs/f2fs/segment.c @@ -2344,7 +2344,9 @@ int f2fs_npages_for_summary_flush(struct f2fs_sb_info *sbi, bool for_ra) */ struct page *f2fs_get_sum_page(struct f2fs_sb_info *sbi, unsigned int segno) { - return f2fs_get_meta_page_nofail(sbi, GET_SUM_BLOCK(sbi, segno)); + if (unlikely(f2fs_cp_error(sbi))) + return ERR_PTR(-EIO); + return f2fs_get_meta_page_retry(sbi, GET_SUM_BLOCK(sbi, segno)); } void f2fs_update_meta_page(struct f2fs_sb_info *sbi, @@ -2616,7 +2618,11 @@ static void change_curseg(struct f2fs_sb_info *sbi, int type) __next_free_blkoff(sbi, curseg, 0); sum_page = f2fs_get_sum_page(sbi, new_segno); - f2fs_bug_on(sbi, IS_ERR(sum_page)); + if (IS_ERR(sum_page)) { + /* GC won't be able to use stale summary pages by cp_error */ + memset(curseg->sum_blk, 0, SUM_ENTRY_SIZE); + return; + } sum_node = (struct f2fs_summary_block *)page_address(sum_page); memcpy(curseg->sum_blk, sum_node, SUM_ENTRY_SIZE); f2fs_put_page(sum_page, 1); @@ -3781,7 +3787,7 @@ int f2fs_lookup_journal_in_cursum(struct f2fs_journal *journal, int type, static struct page *get_current_sit_page(struct f2fs_sb_info *sbi, unsigned int segno) { - return f2fs_get_meta_page_nofail(sbi, current_sit_addr(sbi, segno)); + return f2fs_get_meta_page(sbi, current_sit_addr(sbi, segno)); } static struct page *get_next_sit_page(struct f2fs_sb_info *sbi, -- 2.27.0