divide error: 0000 [#1] PREEMPT SMP KASAN CPU: 0 PID: 10916 Comm: syz-executor.4 Not tainted 5.13.0-rc3-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:tcp_cong_avoid_ai net/ipv4/tcp_cong.c:420 [inline] RIP: 0010:tcp_reno_cong_avoid+0x28c/0x530 net/ipv4/tcp_cong.c:450 Code: df 89 ee e8 d6 bb 0c f9 39 eb 73 15 e8 2d ba 0c f9 4c 8b 3c 24 49 bc 00 00 00 00 00 fc ff df eb 3e e8 18 ba 0c f9 89 d8 31 d2 f5 89 c3 89 d5 48 b9 00 00 00 00 00 fc ff df 41 8a 04 0c 49 89 RSP: 0018:ffffc90009a7f410 EFLAGS: 00010246 RAX: 0000000000000011 RBX: 0000000000000011 RCX: 0000000000040000 RDX: 0000000000000000 RSI: 000000000000338d RDI: 000000000000338e RBP: 0000000000000000 R08: ffffffff88724caa R09: fffffbfff1c70406 R10: fffffbfff1c70406 R11: 0000000000000000 R12: 1ffff1100588ae5f R13: ffff88802c4569c0 R14: 1ffff1100588ae5f R15: ffff88802c4572fc FS: 00007fa989a3f700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000020000100 CR3: 000000002db4e000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tcp_cdg_cong_avoid+0x554/0x1850 net/ipv4/tcp_cdg.c:293 tcp_cong_avoid net/ipv4/tcp_input.c:3084 [inline] tcp_cong_control net/ipv4/tcp_input.c:3442 [inline] tcp_ack+0x24c9/0x4290 net/ipv4/tcp_input.c:3843 tcp_rcv_established+0x7cb/0x2290 net/ipv4/tcp_input.c:5872 tcp_v4_do_rcv+0x3a1/0x870 net/ipv4/tcp_ipv4.c:1694 sk_backlog_rcv include/net/sock.h:1020 [inline] __release_sock+0x1db/0x4d0 net/core/sock.c:2550 __sk_flush_backlog+0x22/0x30 net/core/sock.c:2570 sk_flush_backlog include/net/sock.h:1107 [inline] tcp_sendmsg_locked+0x2b1f/0x40a0 net/ipv4/tcp.c:1305 tcp_sendmsg+0x2c/0x40 net/ipv4/tcp.c:1458 sock_sendmsg_nosec net/socket.c:654 [inline] sock_sendmsg net/socket.c:674 [inline] __sys_sendto+0x541/0x720 net/socket.c:1977 __do_sys_sendto net/socket.c:1989 [inline] __se_sys_sendto net/socket.c:1985 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:1985 do_syscall_64+0x3f/0xb0 arch/x86/entry/common.c:47 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x4665d9 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fa989a3f188 EFLAGS: 00000246 ORIG_RAX: 000000000000002c RAX: ffffffffffffffda RBX: 000000000056c038 RCX: 00000000004665d9 RDX: 00000000fffffd46 RSI: 0000000020000240 RDI: 0000000000000003 RBP: 00000000004bfcb9 R08: 0000000000000000 R09: 00000000000001f4 R10: 00000000000081f4 R11: 0000000000000246 R12: 000000000056c038 R13: 00007ffd81ac5ddf R14: 00007fa989a3f300 R15: 0000000000022000 Modules linked in: ---[ end trace dd70a663dd62f060 ]--- RIP: 0010:tcp_cong_avoid_ai net/ipv4/tcp_cong.c:420 [inline] RIP: 0010:tcp_reno_cong_avoid+0x28c/0x530 net/ipv4/tcp_cong.c:450 Code: df 89 ee e8 d6 bb 0c f9 39 eb 73 15 e8 2d ba 0c f9 4c 8b 3c 24 49 bc 00 00 00 00 00 fc ff df eb 3e e8 18 ba 0c f9 89 d8 31 d2 f5 89 c3 89 d5 48 b9 00 00 00 00 00 fc ff df 41 8a 04 0c 49 89 RSP: 0018:ffffc90009a7f410 EFLAGS: 00010246 RAX: 0000000000000011 RBX: 0000000000000011 RCX: 0000000000040000 RDX: 0000000000000000 RSI: 000000000000338d RDI: 000000000000338e RBP: 0000000000000000 R08: ffffffff88724caa R09: fffffbfff1c70406 R10: fffffbfff1c70406 R11: 0000000000000000 R12: 1ffff1100588ae5f R13: ffff88802c4569c0 R14: 1ffff1100588ae5f R15: ffff88802c4572fc FS: 00007fa989a3f700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000001a19848 CR3: 000000002db4e000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400