------------[ cut here ]------------ msk->pm.local_addr_used == 0 WARNING: net/mptcp/pm_kernel.c:1070 at __mark_subflow_endp_available net/mptcp/pm_kernel.c:1070 [inline], CPU#1: syz.2.4755/16862 WARNING: net/mptcp/pm_kernel.c:1070 at mptcp_nl_remove_subflow_and_signal_addr net/mptcp/pm_kernel.c:1102 [inline], CPU#1: syz.2.4755/16862 WARNING: net/mptcp/pm_kernel.c:1070 at mptcp_pm_nl_del_addr_doit+0xfb1/0x1430 net/mptcp/pm_kernel.c:1209, CPU#1: syz.2.4755/16862 Modules linked in: CPU: 1 UID: 0 PID: 16862 Comm: syz.2.4755 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:__mark_subflow_endp_available net/mptcp/pm_kernel.c:1070 [inline] RIP: 0010:mptcp_nl_remove_subflow_and_signal_addr net/mptcp/pm_kernel.c:1102 [inline] RIP: 0010:mptcp_pm_nl_del_addr_doit+0xfb1/0x1430 net/mptcp/pm_kernel.c:1209 Code: 01 00 00 49 89 c6 e8 9e 03 29 f6 e9 28 fb ff ff e8 94 03 29 f6 48 89 df be 03 00 00 00 e8 17 a0 11 f9 eb a4 e8 80 03 29 f6 90 <0f> 0b 90 e9 ad fe ff ff 89 d9 80 e1 07 38 c1 0f 8c 14 fb ff ff 48 RSP: 0018:ffffc9000551f160 EFLAGS: 00010287 RAX: ffffffff8b9c8830 RBX: 0000000000000000 RCX: 0000000000080000 RDX: ffffc9000d5d9000 RSI: 000000000000386e RDI: 000000000000386f RBP: ffffc9000551f3b0 R08: ffff8880578b3dc7 R09: 1ffff1100af167b8 R10: dffffc0000000000 R11: ffffed100af167b9 R12: 1ffff1100af167b7 R13: ffff8880347b1000 R14: ffff8880578b3300 R15: ffff8880578b3db8 FS: 00007f22bb5b66c0(0000) GS:ffff888125564000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007faebc3456b8 CR3: 000000001fb5a000 CR4: 00000000003526f0 Call Trace: genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1114 genl_family_rcv_msg net/netlink/genetlink.c:1194 [inline] genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1209 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1218 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x80f/0x9b0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg net/socket.c:742 [inline] ____sys_sendmsg+0xa68/0xad0 net/socket.c:2592 ___sys_sendmsg+0x2a5/0x360 net/socket.c:2646 __sys_sendmsg net/socket.c:2678 [inline] __do_sys_sendmsg net/socket.c:2683 [inline] __se_sys_sendmsg net/socket.c:2681 [inline] __x64_sys_sendmsg+0x1bd/0x2a0 net/socket.c:2681 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f22ba79c799 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f22bb5b6028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007f22baa15fa0 RCX: 00007f22ba79c799 RDX: 0000000000000000 RSI: 0000200000000140 RDI: 0000000000000006 RBP: 00007f22ba832bd9 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f22baa16038 R14: 00007f22baa15fa0 R15: 00007fff0b53d508