WARNING in tcp_enter_loss

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3f8a27f9e27b Linux 4.19.211
git tree: linux-4.19.y
console output: https://syzkaller.appspot.com/x/log.txt?x=14770f1bb00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9b9277b418617afe
dashboard link: https://syzkaller.appspot.com/bug?extid=4f123fe39d8f6c911780
compiler: gcc version 10.2.1 20210110 (Debian 10.2.1-6)
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=116c1eabb00000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10ca341db00000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4f123f...@syzkaller.appspotmail.com

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WARNING: CPU: 0 PID: 9143 at net/ipv4/tcp_input.c:1974 tcp_timeout_mark_lost net/ipv4/tcp_input.c:1974 [inline]
WARNING: CPU: 0 PID: 9143 at net/ipv4/tcp_input.c:1974 tcp_enter_loss.cold+0x11/0x18 net/ipv4/tcp_input.c:1986
Kernel panic - not syncing: panic_on_warn set ...

CPU: 0 PID: 9143 Comm: syz-executor988 Not tainted 4.19.211-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1fc/0x2ef lib/dump_stack.c:118
panic+0x26a/0x50e kernel/panic.c:186
__warn.cold+0x20/0x5a kernel/panic.c:541
report_bug+0x262/0x2b0 lib/bug.c:183
fixup_bug arch/x86/kernel/traps.c:178 [inline]
fixup_bug arch/x86/kernel/traps.c:173 [inline]
do_error_trap+0x1d7/0x310 arch/x86/kernel/traps.c:296
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:1038
RIP: 0010:tcp_timeout_mark_lost net/ipv4/tcp_input.c:1974 [inline]
RIP: 0010:tcp_enter_loss.cold+0x11/0x18 net/ipv4/tcp_input.c:1986
Code: ee 55 89 e8 2a eb e0 ff 0f 0b e9 fe 4a c7 fe 48 89 cf e8 10 96 85 f9 eb ce e8 a9 b9 4f f9 48 c7 c7 e0 ee 55 89 e8 08 eb e0 ff <0f> 0b e9 6c 71 c7 fe e8 91 b9 4f f9 48 c7 c7 e0 ee 55 89 e8 f0 ea
RSP: 0018:ffff8880aa1ffa88 EFLAGS: 00010282
RAX: 0000000000000024 RBX: 0000000000000011 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff814dff01 RDI: ffffed101543ff43
RBP: 0000000000000009 R08: 0000000000000024 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000000 R12: dffffc0000000000
R13: ffff8880ae814954 R14: ffffed1015d0281e R15: ffff8880ae8140c0
tcp_retransmit_timer+0x25de/0x33f0 net/ipv4/tcp_timer.c:474
tcp_write_timer_handler+0x5e6/0xa60 net/ipv4/tcp_timer.c:593
tcp_release_cb+0x275/0x2f0 net/ipv4/tcp_output.c:875
release_sock+0xb4/0x1b0 net/core/sock.c:2907
do_tcp_setsockopt.constprop.0+0x42e/0x2340 net/ipv4/tcp.c:3098
tcp_setsockopt net/ipv4/tcp.c:3110 [inline]
tcp_setsockopt+0xb2/0xd0 net/ipv4/tcp.c:3102
__sys_setsockopt+0x14d/0x240 net/socket.c:2013
__do_sys_setsockopt net/socket.c:2024 [inline]
__se_sys_setsockopt net/socket.c:2021 [inline]
__x64_sys_setsockopt+0xba/0x150 net/socket.c:2021
do_syscall_64+0xf9/0x620 arch/x86/entry/common.c:293
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f3989ee58a9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 a1 15 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f3989e722f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000036
RAX: ffffffffffffffda RBX: 00007f3989f6e4b0 RCX: 00007f3989ee58a9
RDX: 0000000000000016 RSI: 0000000000000006 RDI: 0000000000000003
RBP: 00007f3989f6e4bc R08: 000000002000019f R09: 0000000000000000
R10: 0000000020000000 R11: 0000000000000246 R12: 00007f3989f3b70c
R13: 00007f3989f3b4a8 R14: 0000000020000640 R15: 00007f3989f6e4b8
Kernel Offset: disabled
Rebooting in 86400 seconds..


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