syzbot


WARNING in tcp_send_loss_probe

Status: fixed on 2019/03/06 07:43
Subsystems: net
[Documentation on labels]
Fix commit: bf50b606cfd8 tcp: repaired skbs must init their tso_segs
First crash: 1937d, last: 1886d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-414 WARNING in tcp_send_loss_probe C 30 1676d 1687d 0/1 public: reported C repro on 2019/09/10 13:28
linux-4.14 WARNING in tcp_send_loss_probe C done 22 1677d 1687d 1/1 fixed on 2019/12/09 13:28

Sample crash report:
IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_0: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): hsr_slave_1: link becomes ready
IPv6: ADDRCONF(NETDEV_CHANGE): hsr0: link becomes ready
8021q: adding VLAN 0 to HW filter on device batadv0
nf_conntrack: default automatic helper assignment has been turned off for security reasons and CT-based  firewall rule not found. Use the iptables CT target to attach helpers instead.
WARNING: CPU: 0 PID: 7686 at net/ipv4/tcp_output.c:2535 tcp_send_loss_probe+0x771/0x8a0 net/ipv4/tcp_output.c:2535
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 7686 Comm: syz-executor404 Not tainted 5.0.0-rc7+ #85
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x172/0x1f0 lib/dump_stack.c:113
 panic+0x2cb/0x65c kernel/panic.c:214
 __warn.cold+0x20/0x45 kernel/panic.c:571
 report_bug+0x263/0x2b0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:178 [inline]
 fixup_bug arch/x86/kernel/traps.c:173 [inline]
 do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
 do_invalid_op+0x37/0x50 arch/x86/kernel/traps.c:290
 invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:tcp_send_loss_probe+0x771/0x8a0 net/ipv4/tcp_output.c:2535
Code: 88 fc ff ff 4c 89 ef e8 1d 76 c9 fb e9 c8 fc ff ff e8 73 76 c9 fb e9 63 fd ff ff e8 09 76 c9 fb e9 94 f9 ff ff e8 af 73 92 fb <0f> 0b e9 7d fa ff ff e8 a3 73 92 fb 0f b6 1d 07 6e 7b 03 31 ff 89
RSP: 0018:ffff8880ae807cb8 EFLAGS: 00010206
RAX: ffff88808d6061c0 RBX: 0000000000000000 RCX: ffffffff85dd68fb
RDX: 0000000000000100 RSI: ffffffff85dd6dd1 RDI: 0000000000000005
RBP: ffff8880ae807ce8 R08: ffff88808d6061c0 R09: ffffed1013ddf839
R10: ffffed1013ddf838 R11: ffff88809eefc1c3 R12: ffff88808ebe2bc0
R13: ffff88809eefc000 R14: 0000000000008000 R15: ffff88808ebe33d0
 tcp_write_timer_handler+0x4f8/0x8e0 net/ipv4/tcp_timer.c:596
 tcp_write_timer+0x10e/0x1d0 net/ipv4/tcp_timer.c:620
 call_timer_fn+0x190/0x720 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x652/0x1700 kernel/time/timer.c:1694
 __do_softirq+0x266/0x95a kernel/softirq.c:292
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027
 </IRQ>
 do_softirq.part.0+0x11a/0x170 kernel/softirq.c:337
 do_softirq kernel/softirq.c:329 [inline]
 __local_bh_enable_ip+0x211/0x270 kernel/softirq.c:189
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:1908 [inline]
 nf_ct_iterate_cleanup+0x217/0x4e0 net/netfilter/nf_conntrack_core.c:1931
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2016 [inline]
 nf_ct_iterate_cleanup_net+0x133/0x190 net/netfilter/nf_conntrack_core.c:2001
 masq_device_event+0xb5/0xe0 net/ipv6/netfilter/nf_nat_masquerade_ipv6.c:77
 notifier_call_chain+0xc7/0x240 kernel/notifier.c:93
 __raw_notifier_call_chain kernel/notifier.c:394 [inline]
 raw_notifier_call_chain+0x2e/0x40 kernel/notifier.c:401
 call_netdevice_notifiers_info+0x3f/0x90 net/core/dev.c:1739
 call_netdevice_notifiers_extack net/core/dev.c:1751 [inline]
 call_netdevice_notifiers net/core/dev.c:1765 [inline]
 dev_close_many+0x33f/0x6f0 net/core/dev.c:1508
 rollback_registered_many+0x43b/0xfd0 net/core/dev.c:8079
 rollback_registered+0x109/0x1d0 net/core/dev.c:8144
 unregister_netdevice_queue net/core/dev.c:9191 [inline]
 unregister_netdevice_queue+0x1ee/0x2c0 net/core/dev.c:9184
 unregister_netdevice include/linux/netdevice.h:2642 [inline]
 __tun_detach+0xd5b/0x1000 drivers/net/tun.c:727
 tun_detach drivers/net/tun.c:744 [inline]
 tun_chr_close+0xe0/0x180 drivers/net/tun.c:3435
 __fput+0x2df/0x8d0 fs/file_table.c:278
 ____fput+0x16/0x20 fs/file_table.c:309
 task_work_run+0x14a/0x1c0 kernel/task_work.c:113
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0x92c/0x2fd0 kernel/exit.c:875
 do_group_exit+0x135/0x370 kernel/exit.c:979
 get_signal+0x399/0x1d50 kernel/signal.c:2575
 do_signal+0x87/0x1940 arch/x86/kernel/signal.c:816
 exit_to_usermode_loop+0x244/0x2c0 arch/x86/entry/common.c:162
 prepare_exit_to_usermode arch/x86/entry/common.c:197 [inline]
 syscall_return_slowpath arch/x86/entry/common.c:268 [inline]
 do_syscall_64+0x52d/0x610 arch/x86/entry/common.c:293
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x447379
Code: Bad RIP value.
RSP: 002b:00007f9f2c852db8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00000000006dcc38 RCX: 0000000000447379
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00000000006dcc38
RBP: 00000000006dcc30 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dcc3c
R13: 00007fff0a8dd3af R14: 00007f9f2c8539c0 R15: 0000000000000004
Kernel Offset: disabled
Rebooting in 86400 seconds..

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2019/02/24 01:04 upstream e60b5f79bd75 7a06e792 .config console log report syz C ci-upstream-kasan-gce-smack-root
2019/02/24 00:41 upstream e60b5f79bd75 7a06e792 .config console log report syz C ci-upstream-kasan-gce-selinux-root
2019/02/24 00:03 upstream e60b5f79bd75 7a06e792 .config console log report syz C ci-upstream-kasan-gce
2019/02/24 01:01 upstream e60b5f79bd75 7a06e792 .config console log report syz C ci-upstream-kasan-gce-386
2019/02/23 23:46 net-old 61a65d32fe91 7a06e792 .config console log report syz C ci-upstream-net-this-kasan-gce
2019/02/23 21:33 net-next-old e59d790959b4 7a06e792 .config console log report syz C ci-upstream-net-kasan-gce
2019/02/23 23:33 linux-next 94a47529a645 7a06e792 .config console log report syz C ci-upstream-linux-next-kasan-gce-root
2019/02/24 00:47 upstream e60b5f79bd75 7a06e792 .config console log report syz ci-upstream-kasan-gce-root
2019/01/03 09:21 upstream 85f78456f286 06a2b89f .config console log report ci-upstream-kasan-gce-root
* Struck through repros no longer work on HEAD.