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UBSAN: shift-out-of-bounds in net/core/gen_estimator.c:83:38
shift exponent -4 is negative
CPU: 0 PID: 8477 Comm: syz-fuzzer Not tainted 5.11.0-rc3-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+0x1a5/0x6b0 kernel/time/timer.c:1417
 expire_timers kernel/time/timer.c:1462 [inline]
 __run_timers.part.0+0x67c/0xa50 kernel/time/timer.c:1731
 __run_timers kernel/time/timer.c:1712 [inline]
 run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1744
 __do_softirq+0x2bc/0xa29 kernel/softirq.c:343
 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
 invoke_softirq kernel/softirq.c:226 [inline]
 __irq_exit_rcu kernel/softirq.c:420 [inline]
 irq_exit_rcu+0x134/0x200 kernel/softirq.c:432
 sysvec_apic_timer_interrupt+0x4d/0x100 arch/x86/kernel/apic/apic.c:1096
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:628
RIP: 0033:0x42e37a
Code: 00 0f 85 65 01 00 00 31 d2 31 db eb 03 48 ff c2 48 39 ca 0f 8d fe 00 00 00 48 8b b4 d0 58 17 00 00 48 81 fe 00 10 00 00 72 e3 <48> 89 54 24 38 48 89 5c 24 30 48 89 34 24 0f 57 c0 0f 11 44 24 08
RSP: 002b:000000c00003bf60 EFLAGS: 00000206
RAX: 000000c00001e800 RBX: 0000000000000000 RCX: 0000000000000200
RDX: 0000000000000168 RSI: 000000c00ed3a500 RDI: 0000000000000080
RBP: 000000c00003bfa8 R08: 000000000000000b R09: ffffffffffffffff
R10: 00007f90f2785cd8 R11: 000000c00ed2ce40 R12: 0000000000000001
R13: 0000000000000000 R14: 000000c000020f58 R15: 0000000000000000
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