From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1794418405; b=GU+nyJ3cOsfFpbWMC7dpwHh8hAiKPfgJEvtMnEhb5UCk19TZbXx4JMDpSH7Ngj8+x8sd EAhCtQ76IfOVK73zfoQidWk30IfS4GEH78SmVTH5mEo+d1TrDAjVSZqt1xH0gbpV+0mUU 6k9qmll1/XGnmlnONGhXbyGDCsCBojK051LPWqySQK+gEt9jg9r4blYS9toBTsEsvJ27h ANfkQgQCd86aGQ/2IdnyfnB7E/jOXStVFTcDgArqMyPds6L2c6UNJhfodAhQeIDso/SGB xq+icDeM1SJVSy4lUZ2bBC2h5MQBk/Qo+pv0FcRXjiflu899G7HW4YhsLsEGMFPKUuQ== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1794418405; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=prddC7uX/ArCt7Zr6stCtpxGXbyFVHR7u3JGt+1foPw=; b=2CTTKitjPSFMQPnEfd/JAwYXwUrHnSu6n95JsoNRwydSWxilaXADTgrnn1Iymet20LVF EDUJJxV56Q3Tu3PI+l0LEsYcwKSFemjyI7IRI6FdhKXMGNtt9lgGiJI03Xx4fuhAHaogX E/Ujt+NnpEIT8BgbZRpKI0Kr4VNWN0vYm/fTQsHPK7iYT5GEHQrDW1Fl9/aSA+rwuDZZm u7eK2R/eDVDsD+O99TKEyu2HeB4j6qOHBtMc71xVRgkf4FiAWehLOEZ9NcFL7YPXDb1nO gCRlU0/GhrxGjZJ9gNp4w2jiggGEefadi3fKNksYVT0P/Su3VcgyI1sn/rCi5A/gY7g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=SsbUNb2X; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7AC07606A31C for ; Wed, 11 Nov 2026 17:33:25 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=SsbUNb2X Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8F55C1F00A05; Wed, 11 Nov 2026 17:33:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1794418405; bh=prddC7uX/ArCt7Zr6stCtpxGXbyFVHR7u3JGt+1foPw=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=SsbUNb2Xxx3Kf38QJMkkQE2NOWFjT4kgWjud2rmpTIH1qYh8qn23MneY7Xbnhqkpw 8CA7zMQ8kUgeSKCfSnCIQ3tk/vtshRFTrYh36R3qVkWoloquppJCQ63zFT6LQnTxlN Cf//xGPVZ5JboNiBgW6DrbkjCMz/LQESLGYb2YdsGIsmhCQAiWE9RlBAkdbJr3vFlY X7WWn6+87h7gC61HaLgajoxC6qOd0o8jvsSL5HRefKnDqF0+9s99k9cwUeQLwAc1mA /7T80fm4lxo6/y8bd5KH8tEAeVCKcEx9sVthGrqiNt71SlJ9owfJW20RTGyHYLyZL0 Ch/vSxwAgGlMQ== From: Sasha Levin To: stable@vger.kernel.org Cc: Cen Zhang , Andrew Morton , Joseph Qi , Mark Fasheh , Joel Becker , Heming Zhao , Yufan Chen , Christophe JAILLET , Kees Cook , Karl Mehltretter , Sunil Mushran , Jia-Ju Bai , jjzuming@gmail.com, Sasha Levin Subject: [PATCH 5.10.y] ocfs2/cluster: initialize heartbeat regions before publishing them Date: Wed, 11 Nov 2026 12:33:22 -0500 Message-ID: <20261111173303.3608441-1-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20261107062726-failed-5.10-c5b7a30a5172@kernel.org> References: <20261107062726-failed-5.10-c5b7a30a5172@kernel.org> X-Mailing-List: stable@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Cen Zhang [ Upstream commit c5b7a30a5172317e1e3cba61d8c9f9c588c497bb ] A region on o2hb_all_regions must have an initialized config item and name. o2hb_heartbeat_group_make_item() currently links the zeroed region under o2hb_live_lock, drops the lock, and only then initializes hr_item. The lock therefore protects the list without protecting initialization from readers of the published item. With global heartbeat enabled, a DLM_QUERY_REGION from the current joining node can pass the existing-domain and protocol checks while a configfs mkdir creates another region. The DLM locks are not taken by the constructor, and the network worker does not take the configfs subsystem mutex. The following ordering is possible: Configfs mkdir O2net receive worker -------------- -------------------- Allocate reg Lock o2hb_live_lock Link into o2hb_all_regions Unlock o2hb_live_lock dlm_query_region_handler() dlm_match_regions() o2hb_get_all_regions() Lock o2hb_live_lock Copy 32 bytes from NULL name Unlock o2hb_live_lock config_item_init_type_name() The query thus dereferences NULL. Initialize hr_item before linking the region so the existing list lock also orders name initialization before any reader. Reject a failed name allocation, since the initialization helper does not propagate that error. Use config_item_put() on initialized constructor failures to release the name and respect references retained by o2hb_region_pin(). Initialize the list heads, mutex and delayed works needed by o2hb_region_release() before any such put, and leave the list node self-linked after rollback. Keep the existing handler drain before removing a failed published item. KASAN report as below: ================================================================== BUG: KASAN: null-ptr-deref in o2hb_get_all_regions+0xbb/0x1f0 Read of size 32 at addr 0000000000000000 by task kworker/u16:1/14 CPU: 2 UID: 0 PID: 14 Comm: kworker/u16:1 Not tainted 7.3.0-rc4-next-20260921-pmb-ocfs2-functional-v1+ #1 PREEMPT(lazy) Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 Workqueue: o2net o2net_rx_until_empty Call Trace: dump_stack_lvl+0x93/0xd0 kasan_report+0xe0/0x110 ? o2hb_get_all_regions+0xbb/0x1f0 kasan_check_range+0x105/0x1b0 __asan_memcpy+0x23/0x60 o2hb_get_all_regions+0xbb/0x1f0 dlm_query_region_handler+0x4c2/0xc20 ? __pfx_dlm_query_region_handler+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? srso_alias_return_thunk+0x5/0xfbef5 ? trace_hardirqs_on+0x18/0x160 ? srso_alias_return_thunk+0x5/0xfbef5 ? kvm_clock_get_cycles+0x31/0x60 ? srso_alias_return_thunk+0x5/0xfbef5 ? __pfx_dlm_query_region_handler+0x10/0x10 o2net_rx_until_empty+0x1a50/0x3200 ? reacquire_held_locks+0xdd/0x200 ? __pfx_o2net_rx_until_empty+0x10/0x10 ? lock_acquire+0x190/0x300 ? process_one_work+0x935/0x1b40 ? process_one_work+0x834/0x1b40 ? srso_alias_return_thunk+0x5/0xfbef5 ? lock_release+0xc8/0x290 ? srso_alias_return_thunk+0x5/0xfbef5 process_one_work+0x9a8/0x1b40 ? __pfx_process_one_work+0x10/0x10 ? lock_acquire+0x190/0x300 ? lock_is_held_type+0x8f/0x100 ? srso_alias_return_thunk+0x5/0xfbef5 worker_thread+0x65c/0xe40 ? srso_alias_return_thunk+0x5/0xfbef5 ? __kthread_parkme+0x177/0x220 ? srso_alias_return_thunk+0x5/0xfbef5 ? __pfx_worker_thread+0x10/0x10 kthread+0x351/0x460 ? srso_alias_return_thunk+0x5/0xfbef5 ? __pfx_kthread+0x10/0x10 ret_from_fork+0x659/0x940 ? __pfx_ret_from_fork+0x10/0x10 ? srso_alias_return_thunk+0x5/0xfbef5 ? __switch_to+0x74f/0xf70 ? __pfx_kthread+0x10/0x10 ret_from_fork_asm+0x1a/0x30 ================================================================== Link: https://lore.kernel.org/pm-ocfs2-objects-candidate-0079-v5-f931a29339cadc0a2a70@gmail.com Fixes: 536f0741f324 ("ocfs2/cluster: Track number of global heartbeat regions") Signed-off-by: Cen Zhang Signed-off-by: Andrew Morton Reviewed-by: Joseph Qi Assisted-by: LLM Cc: Mark Fasheh Cc: Joel Becker Cc: Heming Zhao Cc: Yufan Chen Cc: Christophe JAILLET Cc: Kees Cook Cc: Karl Mehltretter Cc: Sunil Mushran Cc: Jia-Ju Bai Cc: Cc: [ sashal: Omitted relocation of the mutex, stopping flag and delayed-work initialization. ] Signed-off-by: Sasha Levin --- fs/ocfs2/cluster/heartbeat.c | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) diff --git a/fs/ocfs2/cluster/heartbeat.c b/fs/ocfs2/cluster/heartbeat.c index 9731b9f3b9d84..938425dce6e9a 100644 --- a/fs/ocfs2/cluster/heartbeat.c +++ b/fs/ocfs2/cluster/heartbeat.c @@ -2047,6 +2047,14 @@ static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *g goto free; } + INIT_LIST_HEAD(®->hr_all_item); + INIT_LIST_HEAD(®->hr_handler_list); + config_item_init_type_name(®->hr_item, name, &o2hb_region_type); + if (!config_item_name(®->hr_item)) { + ret = -ENOMEM; + goto put_item; + } + spin_lock(&o2hb_live_lock); reg->hr_region_num = 0; if (o2hb_global_heartbeat_active()) { @@ -2055,22 +2063,19 @@ static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *g if (reg->hr_region_num >= O2NM_MAX_REGIONS) { spin_unlock(&o2hb_live_lock); ret = -EFBIG; - goto free; + goto put_item; } set_bit(reg->hr_region_num, o2hb_region_bitmap); } list_add_tail(®->hr_all_item, &o2hb_all_regions); spin_unlock(&o2hb_live_lock); - config_item_init_type_name(®->hr_item, name, &o2hb_region_type); - /* this is the same way to generate msg key as dlm, for local heartbeat, * name is also the same, so make initial crc value different to avoid * message key conflict. */ reg->hr_key = crc32_le(reg->hr_region_num + O2NM_MAX_REGIONS, name, strlen(name)); - INIT_LIST_HEAD(®->hr_handler_list); ret = o2net_register_handler(O2HB_NEGO_TIMEOUT_MSG, reg->hr_key, sizeof(struct o2hb_nego_msg), o2hb_nego_timeout_handler, @@ -2093,10 +2098,13 @@ static struct config_item *o2hb_heartbeat_group_make_item(struct config_group *g o2net_unregister_handler_list(®->hr_handler_list); remove_item: spin_lock(&o2hb_live_lock); - list_del(®->hr_all_item); + list_del_init(®->hr_all_item); if (o2hb_global_heartbeat_active()) clear_bit(reg->hr_region_num, o2hb_region_bitmap); spin_unlock(&o2hb_live_lock); +put_item: + config_item_put(®->hr_item); + return ERR_PTR(ret); free: kfree(reg); return ERR_PTR(ret); -- 2.53.0