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=-19.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 1827AC11F66 for ; Sat, 10 Jul 2021 23:49:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 084E1613BE for ; Sat, 10 Jul 2021 23:49:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231449AbhGJXvu (ORCPT ); Sat, 10 Jul 2021 19:51:50 -0400 Received: from mail.kernel.org ([198.145.29.99]:38432 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231140AbhGJXvr (ORCPT ); Sat, 10 Jul 2021 19:51:47 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6E1836135B; Sat, 10 Jul 2021 23:49:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1625960942; bh=z8ABZHzMaPXZZRS6oOIBPCfgrs48E9f8t8irqiQADTU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VDRmvq0A1kxSfAsI4loGJ/vnHS827wTxJQpkTihBibha8dJnc58aybXI+mfQJf4SV 3in7EjOWQSTdIq3DPHh9woT25zxru7TyoboMfam6SlYTriuObtXbXljDm/WJwALhhn flzOe7mz78IbjLSwIYYC83L5Ci19qORUZEMIYd9UGrnOF8ax//XHTBCSpBMvs4ykRD xfooxfOdrWxK2XShJ/5UxXrYZmfyMKBjvg2JlehaZJz8X8Cys/yLwqFrOKH34BKlxz f+p+RjptY0dNSqHZlAIZ9Sbic3cTlOgki+DF+OD5b0+frlflqEtcy7qA4uv7UNlVHT pxi/cOCwxm4xA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Chao Yu , syzbot+9d90dad32dd9727ed084@syzkaller.appspotmail.com, Jaegeuk Kim , Sasha Levin , linux-f2fs-devel@lists.sourceforge.net Subject: [PATCH AUTOSEL 5.13 03/53] f2fs: fix to avoid racing on fsync_entry_slab by multi filesystem instances Date: Sat, 10 Jul 2021 19:48:07 -0400 Message-Id: <20210710234857.3220040-3-sashal@kernel.org> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210710234857.3220040-1-sashal@kernel.org> References: <20210710234857.3220040-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Chao Yu [ Upstream commit cad83c968c2ebe97905f900326988ed37146c347 ] As syzbot reported, there is an use-after-free issue during f2fs recovery: Use-after-free write at 0xffff88823bc16040 (in kfence-#10): kmem_cache_destroy+0x1f/0x120 mm/slab_common.c:486 f2fs_recover_fsync_data+0x75b0/0x8380 fs/f2fs/recovery.c:869 f2fs_fill_super+0x9393/0xa420 fs/f2fs/super.c:3945 mount_bdev+0x26c/0x3a0 fs/super.c:1367 legacy_get_tree+0xea/0x180 fs/fs_context.c:592 vfs_get_tree+0x86/0x270 fs/super.c:1497 do_new_mount fs/namespace.c:2905 [inline] path_mount+0x196f/0x2be0 fs/namespace.c:3235 do_mount fs/namespace.c:3248 [inline] __do_sys_mount fs/namespace.c:3456 [inline] __se_sys_mount+0x2f9/0x3b0 fs/namespace.c:3433 do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae The root cause is multi f2fs filesystem instances can race on accessing global fsync_entry_slab pointer, result in use-after-free issue of slab cache, fixes to init/destroy this slab cache only once during module init/destroy procedure to avoid this issue. Reported-by: syzbot+9d90dad32dd9727ed084@syzkaller.appspotmail.com Signed-off-by: Chao Yu Signed-off-by: Jaegeuk Kim Signed-off-by: Sasha Levin --- fs/f2fs/f2fs.h | 2 ++ fs/f2fs/recovery.c | 23 ++++++++++++++--------- fs/f2fs/super.c | 8 +++++++- 3 files changed, 23 insertions(+), 10 deletions(-) diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index c83d90125ebd..a5de48e768d7 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -3566,6 +3566,8 @@ void f2fs_destroy_garbage_collection_cache(void); */ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only); bool f2fs_space_for_roll_forward(struct f2fs_sb_info *sbi); +int __init f2fs_create_recovery_cache(void); +void f2fs_destroy_recovery_cache(void); /* * debug.c diff --git a/fs/f2fs/recovery.c b/fs/f2fs/recovery.c index 422146c6d866..4b2f7d1d5bf4 100644 --- a/fs/f2fs/recovery.c +++ b/fs/f2fs/recovery.c @@ -788,13 +788,6 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only) quota_enabled = f2fs_enable_quota_files(sbi, s_flags & SB_RDONLY); #endif - fsync_entry_slab = f2fs_kmem_cache_create("f2fs_fsync_inode_entry", - sizeof(struct fsync_inode_entry)); - if (!fsync_entry_slab) { - err = -ENOMEM; - goto out; - } - INIT_LIST_HEAD(&inode_list); INIT_LIST_HEAD(&tmp_inode_list); INIT_LIST_HEAD(&dir_list); @@ -867,8 +860,6 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only) } } - kmem_cache_destroy(fsync_entry_slab); -out: #ifdef CONFIG_QUOTA /* Turn quotas off */ if (quota_enabled) @@ -878,3 +869,17 @@ int f2fs_recover_fsync_data(struct f2fs_sb_info *sbi, bool check_only) return ret ? ret : err; } + +int __init f2fs_create_recovery_cache(void) +{ + fsync_entry_slab = f2fs_kmem_cache_create("f2fs_fsync_inode_entry", + sizeof(struct fsync_inode_entry)); + if (!fsync_entry_slab) + return -ENOMEM; + return 0; +} + +void f2fs_destroy_recovery_cache(void) +{ + kmem_cache_destroy(fsync_entry_slab); +} diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index 7d325bfaf65a..096492caaa6b 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -4227,9 +4227,12 @@ static int __init init_f2fs_fs(void) err = f2fs_create_checkpoint_caches(); if (err) goto free_segment_manager_caches; - err = f2fs_create_extent_cache(); + err = f2fs_create_recovery_cache(); if (err) goto free_checkpoint_caches; + err = f2fs_create_extent_cache(); + if (err) + goto free_recovery_cache; err = f2fs_create_garbage_collection_cache(); if (err) goto free_extent_cache; @@ -4278,6 +4281,8 @@ static int __init init_f2fs_fs(void) f2fs_destroy_garbage_collection_cache(); free_extent_cache: f2fs_destroy_extent_cache(); +free_recovery_cache: + f2fs_destroy_recovery_cache(); free_checkpoint_caches: f2fs_destroy_checkpoint_caches(); free_segment_manager_caches: @@ -4303,6 +4308,7 @@ static void __exit exit_f2fs_fs(void) f2fs_exit_sysfs(); f2fs_destroy_garbage_collection_cache(); f2fs_destroy_extent_cache(); + f2fs_destroy_recovery_cache(); f2fs_destroy_checkpoint_caches(); f2fs_destroy_segment_manager_caches(); f2fs_destroy_node_manager_caches(); -- 2.30.2