RBP: 00007f592502d090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f59243e6038 R14: 00007f59243e5fa0 R15: 00007ffdddecd958 Oops: divide error: 0000 [#1] SMP KASAN PTI CPU: 1 UID: 0 PID: 18521 Comm: syz.2.4352 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336 Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00 00 00 e8 c0 49 01 f8 44 89 e0 99 7c 24 1c 41 29 d4 48 bb 00 00 00 00 00 fc ff df e9 80 00 00 00 RSP: 0018:ffffc9000405f640 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888033ffbc80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000405f730 R08: ffff888032b23fc3 R09: 1ffff110065647f8 R10: dffffc0000000000 R11: ffffed10065647f9 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f592502d6c0(0000) GS:ffff888126235000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9d5ae44a69 CR3: 0000000022372000 CR4: 00000000003526f0 Call Trace: tcp_select_window net/ipv4/tcp_output.c:281 [inline] __tcp_transmit_skb+0xbc7/0x3aa0 net/ipv4/tcp_output.c:1568 tcp_transmit_skb net/ipv4/tcp_output.c:1649 [inline] tcp_send_active_reset+0x2d1/0x5b0 net/ipv4/tcp_output.c:3836 mptcp_do_fastclose+0x27e/0x380 net/mptcp/protocol.c:2793 mptcp_disconnect+0x238/0x710 net/mptcp/protocol.c:3253 mptcp_sendmsg_fastopen+0x2f8/0x580 net/mptcp/protocol.c:1776 mptcp_sendmsg+0x1774/0x1980 net/mptcp/protocol.c:1855 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0xe5/0x270 net/socket.c:742 __sys_sendto+0x3bd/0x520 net/socket.c:2244 __do_sys_sendto net/socket.c:2251 [inline] __se_sys_sendto net/socket.c:2247 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2247 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 RIP: 0033:0x7f592418f749 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f592502d038 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 00007f59243e5fa0 RCX: 00007f592418f749 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: 00007f592502d090 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 R13: 00007f59243e6038 R14: 00007f59243e5fa0 R15: 00007ffdddecd958 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__tcp_select_window+0x824/0x1320 net/ipv4/tcp_output.c:3336 Code: ff ff ff 44 89 f1 d3 e0 89 c1 f7 d1 41 01 cc 41 21 c4 e9 a9 00 00 00 e8 ca 49 01 f8 e9 9c 00 00 00 e8 c0 49 01 f8 44 89 e0 99 7c 24 1c 41 29 d4 48 bb 00 00 00 00 00 fc ff df e9 80 00 00 00 RSP: 0018:ffffc9000405f640 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff888033ffbc80 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000405f730 R08: ffff888032b23fc3 R09: 1ffff110065647f8 R10: dffffc0000000000 R11: ffffed10065647f9 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007f592502d6c0(0000) GS:ffff888126235000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f9d5ae44a69 CR3: 0000000022372000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess), 2 bytes skipped: 0: ff 44 89 f1 incl -0xf(%rcx,%rcx,4) 4: d3 e0 shl %cl,%eax 6: 89 c1 mov %eax,%ecx 8: f7 d1 not %ecx a: 41 01 cc add %ecx,%r12d d: 41 21 c4 and %eax,%r12d 10: e9 a9 00 00 00 jmp 0xbe 15: e8 ca 49 01 f8 call 0xf80149e4 1a: e9 9c 00 00 00 jmp 0xbb 1f: e8 c0 49 01 f8 call 0xf80149e4 24: 44 89 e0 mov %r12d,%eax 27: 99 cltd * 28: f7 7c 24 1c idivl 0x1c(%rsp) <-- trapping instruction 2c: 41 29 d4 sub %edx,%r12d 2f: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 36: fc ff df 39: e9 80 00 00 00 jmp 0xbe