x_tables: duplicate underflow at hook 2
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] PREEMPT SMP KASAN
CPU: 1 PID: 0 Comm: swapper/1 Not tainted 4.19.143-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:kfree_skb_list net/core/skbuff.c:670 [inline]
RIP: 0010:skb_release_data+0x6b1/0x920 net/core/skbuff.c:571
Code: e8 84 64 b6 fb 84 db 74 41 e8 4b 63 b6 fb 4c 89 e7 e8 43 f9 d2 fb e9 97 fa ff ff 4c 89 e5 e8 36 63 b6 fb 48 89 e8 48 c1 e8 03 <80> 3c 18 00 0f 85 6d 01 00 00 4c 8b 65 00 48 89 ef e8 09 f5 ff ff
RSP: 0018:ffff8880ae707be0 EFLAGS: 00010247
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff85b34983
RDX: 0000000000000100 RSI: ffffffff85b34e9a RDI: ffff88800012fc88
RBP: 0000000000000007 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88800012fc80 R15: ffff88800012fcb0
FS:  0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7370a7f740 CR3: 0000000040c6c000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 skb_release_all net/core/skbuff.c:631 [inline]
 __kfree_skb net/core/skbuff.c:645 [inline]
 kfree_skb+0x11a/0x3d0 net/core/skbuff.c:663
 inet_frag_rbtree_purge+0x9b/0xd0 net/ipv4/inet_fragment.c:196
 inet_frag_destroy+0x1d4/0x230 net/ipv4/inet_fragment.c:227
 inet_frag_put include/net/inet_frag.h:125 [inline]
 ipq_put+0x3b/0x50 net/ipv4/ip_fragment.c:112
 call_timer_fn+0x177/0x700 kernel/time/timer.c:1338
 expire_timers+0x243/0x4e0 kernel/time/timer.c:1375
 __run_timers kernel/time/timer.c:1703 [inline]
 run_timer_softirq+0x21c/0x670 kernel/time/timer.c:1716
 __do_softirq+0x26c/0x9a0 kernel/softirq.c:292
 invoke_softirq kernel/softirq.c:372 [inline]
 irq_exit+0x215/0x260 kernel/softirq.c:412
 exiting_irq arch/x86/include/asm/apic.h:544 [inline]
 smp_apic_timer_interrupt+0x136/0x550 arch/x86/kernel/apic/apic.c:1094
 apic_timer_interrupt+0xf/0x20 arch/x86/entry/entry_64.S:894
 </IRQ>
RIP: 0010:native_safe_halt+0xe/0x10 arch/x86/include/asm/irqflags.h:61
Code: 48 89 df e8 74 45 62 fa e9 2e ff ff ff 48 89 df e8 67 45 62 fa eb 82 90 90 90 90 90 e9 07 00 00 00 0f 00 2d f4 5b 4a 00 fb f4 <c3> 90 e9 07 00 00 00 0f 00 2d e4 5b 4a 00 f4 c3 90 90 41 56 41 55
RSP: 0018:ffff8880a9f4fd58 EFLAGS: 00000286 ORIG_RAX: ffffffffffffff13
RAX: 1ffffffff11a4b6c RBX: dffffc0000000000 RCX: 0000000000000000
RDX: dffffc0000000000 RSI: 0000000000000001 RDI: ffff8880a9f3cc44
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: ffffffff88d25b50
R13: 1ffff110153e9fb5 R14: 0000000000000000 R15: 0000000000000000
 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline]
 default_idle+0x49/0x310 arch/x86/kernel/process.c:557
 cpuidle_idle_call kernel/sched/idle.c:153 [inline]
 do_idle+0x2ec/0x4b0 kernel/sched/idle.c:263
 cpu_startup_entry+0xc5/0xe0 kernel/sched/idle.c:369
 start_secondary+0x41f/0x580 arch/x86/kernel/smpboot.c:271
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243
Modules linked in:
---[ end trace c850b0aa8cbf707d ]---
RIP: 0010:kfree_skb_list net/core/skbuff.c:670 [inline]
RIP: 0010:skb_release_data+0x6b1/0x920 net/core/skbuff.c:571
Code: e8 84 64 b6 fb 84 db 74 41 e8 4b 63 b6 fb 4c 89 e7 e8 43 f9 d2 fb e9 97 fa ff ff 4c 89 e5 e8 36 63 b6 fb 48 89 e8 48 c1 e8 03 <80> 3c 18 00 0f 85 6d 01 00 00 4c 8b 65 00 48 89 ef e8 09 f5 ff ff
RSP: 0018:ffff8880ae707be0 EFLAGS: 00010247
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffffffff85b34983
RDX: 0000000000000100 RSI: ffffffff85b34e9a RDI: ffff88800012fc88
RBP: 0000000000000007 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: ffff88800012fc80 R15: ffff88800012fcb0
FS:  0000000000000000(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f7370a7f740 CR3: 0000000040c6c000 CR4: 00000000001426e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400