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UBSAN: shift-out-of-bounds in net/core/gen_estimator.c:83:38
shift exponent -236 is negative
CPU: 1 PID: 25812 Comm: syz-executor.3 Not tainted 5.10.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:79 [inline]
 dump_stack+0x107/0x163 lib/dump_stack.c:120
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:148
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x181 lib/ubsan.c:395
 est_timer.cold+0xbb/0x12d net/core/gen_estimator.c:83
 call_timer_fn+0x1a5/0x710 kernel/time/timer.c:1417
 expire_timers kernel/time/timer.c:1462 [inline]
 __run_timers+0x6f6/0xb10 kernel/time/timer.c:1731
 run_timer_softirq+0x7d/0x140 kernel/time/timer.c:1744
 __do_softirq+0x2cb/0xad5 kernel/softirq.c:298
 asm_call_irq_on_stack+0xf/0x20
 </IRQ>
 __run_on_irqstack arch/x86/include/asm/irq_stack.h:26 [inline]
 run_on_irqstack_cond arch/x86/include/asm/irq_stack.h:77 [inline]
 do_softirq_own_stack+0xaa/0xd0 arch/x86/kernel/irq_64.c:77
 do_softirq kernel/softirq.c:343 [inline]
 do_softirq+0x7e/0x80 kernel/softirq.c:330
 __local_bh_enable_ip+0xf0/0x110 kernel/softirq.c:195
 local_bh_enable include/linux/bottom_half.h:32 [inline]
 get_next_corpse net/netfilter/nf_conntrack_core.c:2221 [inline]
 nf_ct_iterate_cleanup+0x11f/0x3a0 net/netfilter/nf_conntrack_core.c:2244
 nf_ct_iterate_cleanup_net net/netfilter/nf_conntrack_core.c:2329 [inline]
 nf_ct_iterate_cleanup_net+0x113/0x170 net/netfilter/nf_conntrack_core.c:2314
 masq_device_event+0xae/0xe0 net/netfilter/nf_nat_masquerade.c:88
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
 call_netdevice_notifiers_info+0xb5/0x150 net/core/dev.c:2022
 call_netdevice_notifiers_extack net/core/dev.c:2034 [inline]
 call_netdevice_notifiers net/core/dev.c:2048 [inline]
 dev_close_many+0x30b/0x640 net/core/dev.c:1623
 rollback_registered_many+0x3fa/0x1610 net/core/dev.c:9454
 rollback_registered net/core/dev.c:9522 [inline]
 unregister_netdevice_queue+0x2dd/0x590 net/core/dev.c:10682
 unregister_netdevice include/linux/netdevice.h:2868 [inline]
 ppp_release+0x216/0x240 drivers/net/ppp/ppp_generic.c:404
 __fput+0x285/0x930 fs/file_table.c:281
 task_work_run+0xdd/0x190 kernel/task_work.c:168
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:174 [inline]
 exit_to_user_mode_prepare+0x249/0x250 kernel/entry/common.c:201
 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline]
 syscall_exit_to_user_mode+0x19/0x50 kernel/entry/common.c:302
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x417bf1
Code: 75 14 b8 03 00 00 00 0f 05 48 3d 01 f0 ff ff 0f 83 a4 1a 00 00 c3 48 83 ec 08 e8 0a fc ff ff 48 89 04 24 b8 03 00 00 00 0f 05 <48> 8b 3c 24 48 89 c2 e8 53 fc ff ff 48 89 d0 48 83 c4 08 48 3d 01
RSP: 002b:00007ffef987faa0 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000007 RCX: 0000000000417bf1
RDX: 0000000000000000 RSI: 0000000080000000 RDI: 0000000000000006
RBP: 0000000000000001 R08: 000000000000120a R09: 00000000c886d20e
R10: 00007ffef987fb80 R11: 0000000000000293 R12: ffffffffffffffff
R13: 000000000011bf2c R14: 00000000000003e8 R15: 000000000119bf8c
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