------------[ 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.4.4672/24583
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.4.4672/24583
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.4.4672/24583
Modules linked in:
CPU: 1 UID: 0 PID: 24583 Comm: syz.4.4672 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 7e 4d 29 f6 e9 28 fb ff ff e8 74 4d 29 f6 48 89 df be 03 00 00 00 e8 27 d3 11 f9 eb a4 e8 60 4d 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:ffffc90002797160 EFLAGS: 00010287
RAX: ffffffff8b9c3f30 RBX: 0000000000000000 RCX: 0000000000080000
RDX: ffffc900059a1000 RSI: 0000000000004286 RDI: 0000000000004287
RBP: ffffc900027973b0 R08: ffff88806be71787 R09: 1ffff1100d7ce2f0
R10: dffffc0000000000 R11: ffffed100d7ce2f1 R12: 1ffff1100d7ce2ef
R13: ffff8880992ed000 R14: ffff88806be70cc0 R15: ffff88806be71778
FS:  00007f9bdaf866c0(0000) GS:ffff888125566000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c37b166 CR3: 000000007a114000 CR4: 00000000003526f0
Call Trace:
 <TASK>
 genl_family_rcv_msg_doit+0x22a/0x330 net/netlink/genetlink.c:1115
 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline]
 genl_rcv_msg+0x61c/0x7a0 net/netlink/genetlink.c:1210
 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550
 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219
 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: 0033:0x7f9bda19c629
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:00007f9bdaf86028 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f9bda415fa0 RCX: 00007f9bda19c629
RDX: 0000000000000000 RSI: 0000200000000140 RDI: 000000000000000a
RBP: 00007f9bda232b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9bda416038 R14: 00007f9bda415fa0 R15: 00007fff9038adb8
 </TASK>