From patchwork Wed Feb 12 12:46:54 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Gavrilov Ilia X-Patchwork-Id: 13971583 X-Patchwork-Delegate: kuba@kernel.org Received: from mx0.infotecs.ru (mx0.infotecs.ru [91.244.183.115]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 33587B673; Wed, 12 Feb 2025 12:46:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.244.183.115 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739364420; cv=none; b=HzqlnEl/AEBptXdAkbt1Kl/Ce20HJ5URIZpU9pJHuvAo+2WqIvAhU3uRAaSuvRFAlr+DsuOswEVPWpNdbLWZYDUi3J7d8IIhVz0T10FMx46Gi1BS/WHEJhJuTDS2/OyNX9i8JQMdcUt8jnSu3kkCjvP/OL0XwfiTWEgTPM3VWks= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1739364420; c=relaxed/simple; bh=abNS+SlQsH7zUv/rrq3F4u5WzmNh3AVn3E329/VKTRI=; h=From:To:CC:Subject:Date:Message-ID:Content-Type:MIME-Version; b=fbp2Wg/DV293bfqVQkl2tGattU+S0sOdYKc497TJqo4p5eu6MO3x8PduAyC13zwtbuldYSwUPJiZXzbkFbL5EoeboV4PKz5ULmd6dSc1E2MgwUwBqUVmo2OXK9GPKMbLZDdcDPNzSluR78nJokiuxH1LGm37QyriCGlw7cq/eUA= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=infotecs.ru; spf=pass smtp.mailfrom=infotecs.ru; dkim=pass (1024-bit key) header.d=infotecs.ru header.i=@infotecs.ru header.b=yZCqFt1D; arc=none smtp.client-ip=91.244.183.115 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=infotecs.ru Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=infotecs.ru Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=infotecs.ru header.i=@infotecs.ru header.b="yZCqFt1D" Received: from mx0.infotecs-nt (localhost [127.0.0.1]) by mx0.infotecs.ru (Postfix) with ESMTP id 736191077FB9; Wed, 12 Feb 2025 15:46:54 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 mx0.infotecs.ru 736191077FB9 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=infotecs.ru; s=mx; t=1739364414; bh=gbwi/FK25uRXyNl2UyXm8Vw8PER/cVoK4GZhMFjqzPo=; h=From:To:CC:Subject:Date:From; b=yZCqFt1DuPdRAU7nD+lSWy929B5w/nSk9k6AZMw/CYmK/ipBDMk1NUa+gG56QAsmz 92ubghJz4NPLkIbS0asZCOhBnSH43esIEkpFZIJ/SXN1+5iss2AI679lPt20y36sQj 5KkotLJAMvWGGSEA1/no9ygdOztFMHvcBq/+GrIU= Received: from msk-exch-01.infotecs-nt (msk-exch-01.infotecs-nt [10.0.7.191]) by mx0.infotecs-nt (Postfix) with ESMTP id 707423045337; Wed, 12 Feb 2025 15:46:54 +0300 (MSK) From: Gavrilov Ilia To: Neil Horman CC: "David S. Miller" , Eric Dumazet , Jakub Kicinski , Paolo Abeni , Simon Horman , "netdev@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" , "lvc-project@linuxtesting.org" Subject: [PATCH net] drop_monitor: fix incorrect initialization order Thread-Topic: [PATCH net] drop_monitor: fix incorrect initialization order Thread-Index: AQHbfUwxqBopjNb91026ifHBiYFNFQ== Date: Wed, 12 Feb 2025 12:46:54 +0000 Message-ID: <20250212124653.297647-1-Ilia.Gavrilov@infotecs.ru> Accept-Language: ru-RU, en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-exclaimer-md-config: 208ac3cd-1ed4-4982-a353-bdefac89ac0a Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-KLMS-Rule-ID: 5 X-KLMS-Message-Action: clean X-KLMS-AntiSpam-Status: not scanned, disabled by settings X-KLMS-AntiSpam-Interceptor-Info: not scanned X-KLMS-AntiPhishing: Clean, bases: 2025/02/12 10:45:00 X-KLMS-AntiVirus: Kaspersky Security for Linux Mail Server, version 8.0.3.30, bases: 2025/02/12 10:17:00 #27183182 X-KLMS-AntiVirus-Status: Clean, skipped X-Patchwork-Delegate: kuba@kernel.org Syzkaller reports the following bug: BUG: spinlock bad magic on CPU#1, syz-executor.0/7995 lock: 0xffff88805303f3e0, .magic: 00000000, .owner: /-1, .owner_cpu: 0 CPU: 1 PID: 7995 Comm: syz-executor.0 Tainted: G E 5.10.209+ #1 Hardware name: VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform, BIOS 6.00 11/12/2020 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x119/0x179 lib/dump_stack.c:118 debug_spin_lock_before kernel/locking/spinlock_debug.c:83 [inline] do_raw_spin_lock+0x1f6/0x270 kernel/locking/spinlock_debug.c:112 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:117 [inline] _raw_spin_lock_irqsave+0x50/0x70 kernel/locking/spinlock.c:159 reset_per_cpu_data+0xe6/0x240 [drop_monitor] net_dm_cmd_trace+0x43d/0x17a0 [drop_monitor] genl_family_rcv_msg_doit+0x22f/0x330 net/netlink/genetlink.c:739 genl_family_rcv_msg net/netlink/genetlink.c:783 [inline] genl_rcv_msg+0x341/0x5a0 net/netlink/genetlink.c:800 netlink_rcv_skb+0x14d/0x440 net/netlink/af_netlink.c:2497 genl_rcv+0x29/0x40 net/netlink/genetlink.c:811 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x54b/0x800 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x914/0xe00 net/netlink/af_netlink.c:1916 sock_sendmsg_nosec net/socket.c:651 [inline] __sock_sendmsg+0x157/0x190 net/socket.c:663 ____sys_sendmsg+0x712/0x870 net/socket.c:2378 ___sys_sendmsg+0xf8/0x170 net/socket.c:2432 __sys_sendmsg+0xea/0x1b0 net/socket.c:2461 do_syscall_64+0x30/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x62/0xc7 RIP: 0033:0x7f3f9815aee9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f3f972bf0c8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f3f9826d050 RCX: 00007f3f9815aee9 RDX: 0000000020000000 RSI: 0000000020001300 RDI: 0000000000000007 RBP: 00007f3f981b63bd R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000006e R14: 00007f3f9826d050 R15: 00007ffe01ee6768 If drop_monitor is built as a kernel module, syzkaller may have time to send a netlink NET_DM_CMD_START message during the module loading. This will call the net_dm_monitor_start() function that uses a spinlock that has not yet been initialized. To fix this, let's place resource initialization above the registration of a generic netlink family. Found by InfoTeCS on behalf of Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol") Signed-off-by: Ilia Gavrilov --- net/core/drop_monitor.c | 13 ++++++------- 1 file changed, 6 insertions(+), 7 deletions(-) diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c index 6efd4cccc9dd..9755d2010e70 100644 --- a/net/core/drop_monitor.c +++ b/net/core/drop_monitor.c @@ -1734,6 +1734,11 @@ static int __init init_net_drop_monitor(void) return -ENOSPC; } + for_each_possible_cpu(cpu) { + net_dm_cpu_data_init(cpu); + net_dm_hw_cpu_data_init(cpu); + } + rc = genl_register_family(&net_drop_monitor_family); if (rc) { pr_err("Could not create drop monitor netlink family\n"); @@ -1749,11 +1754,6 @@ static int __init init_net_drop_monitor(void) rc = 0; - for_each_possible_cpu(cpu) { - net_dm_cpu_data_init(cpu); - net_dm_hw_cpu_data_init(cpu); - } - goto out; out_unreg: @@ -1772,13 +1772,12 @@ static void exit_net_drop_monitor(void) * Because of the module_get/put we do in the trace state change path * we are guaranteed not to have any current users when we get here */ + BUG_ON(genl_unregister_family(&net_drop_monitor_family)); for_each_possible_cpu(cpu) { net_dm_hw_cpu_data_fini(cpu); net_dm_cpu_data_fini(cpu); } - - BUG_ON(genl_unregister_family(&net_drop_monitor_family)); } module_init(init_net_drop_monitor);