From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-il1-f207.google.com (mail-il1-f207.google.com [209.85.166.207]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A78DD74BE1 for ; Mon, 17 Nov 2025 07:50:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.166.207 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763365830; cv=none; b=O9/4MpwSM07IvBNPB2dmrC6P2rBYeQBJZ8vFIeIbdr0VMLlMlHbi9GW1ukCtz67T9Vcpe0NCS3EVYZQj5sMptMClwzQuIVYyRfejolXyuGJ6W2paznc+pZ6lGq4IWB0mZzTUs+ZIGfVWYoXmh5o0AEmcoBd4JVQArpPr13Nwg2k= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763365830; c=relaxed/simple; bh=fyv8Tw1lT47IXGG0zH/8JBH66A640H5gzWsNKy+mm+Y=; h=MIME-Version:Date:Message-ID:Subject:From:To:Content-Type; b=uQFXQwskXc4I57ZVAh6Tf6dIPGYm82TlRa0GKgx2b1meMJweMMG0oPLR1SMJkyxGYL/o8GOfH7Lh3CnYj/XemQSmHrkry2nmso5TWFVy4gufUlqEaYM78qrKRTz8NiUCxNW11O7QLXHWPGRD68/LqOcDXC369HMVXUCd8UMWKY8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com; arc=none smtp.client-ip=209.85.166.207 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=none dis=none) header.from=syzkaller.appspotmail.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=M3KW2WVRGUFZ5GODRSRYTGD7.apphosting.bounces.google.com Received: by mail-il1-f207.google.com with SMTP id e9e14a558f8ab-4330bc0373bso39162375ab.0 for ; Sun, 16 Nov 2025 23:50:28 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1763365828; x=1763970628; h=to:from:subject:message-id:date:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=l6/TbSrkr4zDJJCyMBLL6uCe6ZYiDDdqBbWagbSeP44=; b=H29XXMQfc1eSwLSYEdyLXTFwVskOe+PExiTy1AlsqbtZrfGH0xMTRG+fLsf29KwXQF rtB3hmTn9FSEseyYQIW00QsLbJqsLZBBdA0Z+2sf/OfTAsIQ96XFLkrqD/RxL8WzcVws yU9ycHodV9llQc0qkdM2aZxBVTDj6h9vCLOSJXXwmLB7v/BrL+yCmHDVoCnN2AcytYER QFL4d3a+89jljYM69j+fLzkF7/g3BJgf8KYvhm3qbHJh9AZBhuoyRWSM8Yoha4UI5zBn vMxHWWiYddVWNj7LnIizfs87x+bvk1/YeMe6vH40MIl0qEIZIo1VM8yzfS8FmghtYIPg Q51w== X-Forwarded-Encrypted: i=1; AJvYcCXYlRAcgsT5S8/kpM8q6h/aW+N8033rc3wugkb2PliPtOU9XuNWECzgwwflQutVcplzVH3kZQPykk3HrTY=@vger.kernel.org X-Gm-Message-State: AOJu0Yx1WxrdwHF9juYuv+q/g4SNyOmnJzAc8vx5kRBPbzvlT8ouQzcG aAt1bkxKVq34AfPhDA4szk1JR/ZEHPzzfTjH5Y8otwnhfX0Mg6iY4QHfEydBkTIfX3kakamA//9 9l5SpdycTcepBNrMtliUz7iHYFl0CGXrq1WxuNVsG9vdz9pc1XUKsYroJeHs= X-Google-Smtp-Source: AGHT+IHQasjwkGY8eE2+Q7KkRWtGGeGU1a3mIwfBshOsRIcWj7hcUtwqj8jhePFLTcYWSDL2edKD7zSY/PvTcoSFlgVNdkx7XUFK Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Received: by 2002:a05:6e02:1b0e:b0:434:96ea:ff73 with SMTP id e9e14a558f8ab-43496eb02acmr103520745ab.35.1763365827787; Sun, 16 Nov 2025 23:50:27 -0800 (PST) Date: Sun, 16 Nov 2025 23:50:27 -0800 X-Google-Appengine-App-Id: s~syzkaller X-Google-Appengine-App-Id-Alias: syzkaller Message-ID: <691ad3c3.a70a0220.f6df1.0004.GAE@google.com> Subject: [syzbot] [mptcp?] KASAN: slab-use-after-free Read in mptcp_pm_del_add_timer From: syzbot To: davem@davemloft.net, edumazet@google.com, geliang@kernel.org, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, martineau@kernel.org, matttbe@kernel.org, mptcp@lists.linux.dev, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com Content-Type: text/plain; charset="UTF-8" Hello, syzbot found the following issue on: HEAD commit: 98ac9cc4b445 Merge tag 'f2fs-fix-6.18-rc2' of git://git.ke.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=1712bdcd980000 kernel config: https://syzkaller.appspot.com/x/.config?x=af9170887d81dea1 dashboard link: https://syzkaller.appspot.com/bug?extid=2a6fbf0f0530375968df compiler: Debian clang version 20.1.8 (++20250708063551+0c9f909b7976-1~exp1~20250708183702.136), Debian LLD 20.1.8 Unfortunately, I don't have any reproducer for this issue yet. Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/aa708867a71c/disk-98ac9cc4.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/5d853b65c8dc/vmlinux-98ac9cc4.xz kernel image: https://storage.googleapis.com/syzbot-assets/f0f012153d60/bzImage-98ac9cc4.xz IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+2a6fbf0f0530375968df@syzkaller.appspotmail.com ================================================================== BUG: KASAN: slab-use-after-free in __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616 Read of size 4 at addr ffff8880311e4150 by task kworker/1:1/44 CPU: 1 UID: 0 PID: 44 Comm: kworker/1:1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025 Workqueue: events mptcp_worker Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __timer_delete_sync+0x372/0x3f0 kernel/time/timer.c:1616 sk_stop_timer_sync+0x1b/0x90 net/core/sock.c:3631 mptcp_pm_del_add_timer+0x283/0x310 net/mptcp/pm.c:362 mptcp_incoming_options+0x1357/0x1f60 net/mptcp/options.c:1174 tcp_data_queue+0xca/0x6450 net/ipv4/tcp_input.c:5361 tcp_rcv_established+0x1335/0x2670 net/ipv4/tcp_input.c:6441 tcp_v4_do_rcv+0x98b/0xbf0 net/ipv4/tcp_ipv4.c:1931 tcp_v4_rcv+0x252a/0x2dc0 net/ipv4/tcp_ipv4.c:2374 ip_protocol_deliver_rcu+0x221/0x440 net/ipv4/ip_input.c:205 ip_local_deliver_finish+0x3bb/0x6f0 net/ipv4/ip_input.c:239 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 NF_HOOK+0x30c/0x3a0 include/linux/netfilter.h:318 __netif_receive_skb_one_core net/core/dev.c:6079 [inline] __netif_receive_skb+0x143/0x380 net/core/dev.c:6192 process_backlog+0x31e/0x900 net/core/dev.c:6544 __napi_poll+0xb6/0x540 net/core/dev.c:7594 napi_poll net/core/dev.c:7657 [inline] net_rx_action+0x5f7/0xda0 net/core/dev.c:7784 handle_softirqs+0x22f/0x710 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_bh_enable_ip+0x1a0/0x2e0 kernel/softirq.c:302 mptcp_pm_send_ack net/mptcp/pm.c:210 [inline] mptcp_pm_addr_send_ack+0x41f/0x500 net/mptcp/pm.c:-1 mptcp_pm_worker+0x174/0x320 net/mptcp/pm.c:1002 mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 44: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 poison_kmalloc_redzone mm/kasan/common.c:400 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417 kasan_kmalloc include/linux/kasan.h:262 [inline] __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5748 kmalloc_noprof include/linux/slab.h:957 [inline] mptcp_pm_alloc_anno_list+0x104/0x460 net/mptcp/pm.c:385 mptcp_pm_create_subflow_or_signal_addr+0xf9d/0x1360 net/mptcp/pm_kernel.c:355 mptcp_pm_nl_fully_established net/mptcp/pm_kernel.c:409 [inline] __mptcp_pm_kernel_worker+0x417/0x1ef0 net/mptcp/pm_kernel.c:1529 mptcp_pm_worker+0x1ee/0x320 net/mptcp/pm.c:1008 mptcp_worker+0xd5/0x1170 net/mptcp/protocol.c:2762 process_one_work kernel/workqueue.c:3263 [inline] process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Freed by task 6630: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587 kasan_save_free_info mm/kasan/kasan.h:406 [inline] poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2523 [inline] slab_free mm/slub.c:6611 [inline] kfree+0x197/0x950 mm/slub.c:6818 mptcp_remove_anno_list_by_saddr+0x2d/0x40 net/mptcp/pm.c:158 mptcp_pm_flush_addrs_and_subflows net/mptcp/pm_kernel.c:1209 [inline] mptcp_nl_flush_addrs_list net/mptcp/pm_kernel.c:1240 [inline] mptcp_pm_nl_flush_addrs_doit+0x593/0xbb0 net/mptcp/pm_kernel.c:1281 genl_family_rcv_msg_doit+0x215/0x300 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x60e/0x790 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x208/0x470 net/netlink/af_netlink.c:2552 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x846/0xa10 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x805/0xb30 net/netlink/af_netlink.c:1896 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 ____sys_sendmsg+0x508/0x820 net/socket.c:2630 ___sys_sendmsg+0x21f/0x2a0 net/socket.c:2684 __sys_sendmsg net/socket.c:2716 [inline] __do_sys_sendmsg net/socket.c:2721 [inline] __se_sys_sendmsg net/socket.c:2719 [inline] __x64_sys_sendmsg+0x1a1/0x260 net/socket.c:2719 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880311e4100 which belongs to the cache kmalloc-192 of size 192 The buggy address is located 80 bytes inside of freed 192-byte region [ffff8880311e4100, ffff8880311e41c0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x311e4 flags: 0x80000000000000(node=0|zone=1) page_type: f5(slab) raw: 0080000000000000 ffff88813ff263c0 ffffea0000c42a00 dead000000000004 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 5806, tgid 5806 (syz-executor), ts 106874965631, free_ts 106848734160 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850 prep_new_page mm/page_alloc.c:1858 [inline] get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416 alloc_slab_page mm/slub.c:3039 [inline] allocate_slab+0x96/0x3a0 mm/slub.c:3212 new_slab mm/slub.c:3266 [inline] ___slab_alloc+0xb12/0x13f0 mm/slub.c:4636 __slab_alloc+0xc6/0x1f0 mm/slub.c:4755 __slab_alloc_node mm/slub.c:4831 [inline] slab_alloc_node mm/slub.c:5253 [inline] __kmalloc_cache_noprof+0xec/0x6c0 mm/slub.c:5743 kmalloc_noprof include/linux/slab.h:957 [inline] addr_event+0xc3/0x470 drivers/infiniband/core/roce_gid_mgmt.c:861 inet6addr_event+0x9f/0xd0 drivers/infiniband/core/roce_gid_mgmt.c:904 notifier_call_chain+0x1b6/0x3e0 kernel/notifier.c:85 atomic_notifier_call_chain+0xda/0x180 kernel/notifier.c:223 ipv6_add_addr+0xdf1/0x10e0 net/ipv6/addrconf.c:1186 inet6_addr_add+0x393/0xb40 net/ipv6/addrconf.c:3050 inet6_rtm_newaddr+0x93d/0xd20 net/ipv6/addrconf.c:5059 rtnetlink_rcv_msg+0x7cf/0xb70 net/core/rtnetlink.c:6954 page last free pid 28 tgid 28 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1394 [inline] __free_frozen_pages+0xfb6/0x1140 mm/page_alloc.c:2906 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core kernel/rcu/tree.c:2861 [inline] rcu_cpu_kthread+0xbf6/0x1b50 kernel/rcu/tree.c:2949 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Memory state around the buggy address: ffff8880311e4000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880311e4080: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc >ffff8880311e4100: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880311e4180: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc ffff8880311e4200: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ================================================================== --- This report is generated by a bot. 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