================================================================================
UBSAN: shift-out-of-bounds in net/core/gen_estimator.c:83:38
shift exponent -95 is negative
CPU: 1 PID: 29555 Comm: kworker/u4:0 Not tainted 5.11.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
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: 0010:rcu_read_lock include/linux/rcupdate.h:649 [inline]
RIP: 0010:batadv_nc_purge_orig_hash net/batman-adv/network-coding.c:404 [inline]
RIP: 0010:batadv_nc_worker+0x13d/0xe50 net/batman-adv/network-coding.c:715
Code: 31 d2 31 f6 b9 02 00 00 00 68 63 e1 9a 88 48 c7 c7 20 39 37 8b e8 93 ea bd f8 e8 2e b1 5e 00 31 ff 89 c5 89 c6 e8 93 ef d7 f8 <85> ed 58 74 1e e8 09 e8 d7 f8 0f b6 2d 42 7e 54 04 31 ff 89 ee e8
RSP: 0018:ffffc900029d7c88 EFLAGS: 00000246
RAX: 0000000000000000 RBX: ffff88805c7987f0 RCX: 0000000000000001
RDX: 0000000000000000 RSI: ffff888079d48000 RDI: 0000000000000003
RBP: 0000000000000001 R08: 0000000000000000 R09: ffffffff8ed317a7
R10: ffffffff889ae1ad R11: 0000000000000000 R12: ffffc900029d7da8
R13: 0000000000000000 R14: dffffc0000000000 R15: 00000000000000fe
 process_one_work+0x98d/0x15f0 kernel/workqueue.c:2275
 worker_thread+0x64c/0x1120 kernel/workqueue.c:2421
 kthread+0x3b1/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296
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