------------[ cut here ]------------
sk->sk_forward_alloc
WARNING: net/ipv4/af_inet.c:162 at inet_sock_destruct+0x653/0x800 net/ipv4/af_inet.c:162, CPU#0: swapper/0/0
Modules linked in:
CPU: 0 UID: 0 PID: 0 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:inet_sock_destruct+0x653/0x800 net/ipv4/af_inet.c:162
Code: 4e 4d ff e9 06 fd ff ff e8 ca 7f fd f7 90 0f 0b 90 e9 35 fe ff ff e8 bc 7f fd f7 90 0f 0b 90 e9 c5 fe ff ff e8 ae 7f fd f7 90 <0f> 0b 90 e9 04 ff ff ff e8 a0 7f fd f7 90 0f 0b 90 e9 65 fe ff ff
RSP: 0018:ffffc90000007d88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff88803e398000 RCX: ffffffff8a0b30f7
RDX: ffffffff8e4955c0 RSI: ffffffff8a0b31f2 RDI: ffffffff8e4955c0
RBP: 0000000000000090 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000090 R11: 000000000000a9e2 R12: ffff88803e398000
R13: ffff88803e398090 R14: ffffffff81ee353d R15: 0000000000000009
FS:  0000000000000000(0000) GS:ffff8880d636a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fc16ebbdff8 CR3: 000000000e596000 CR4: 0000000000352ef0
Call Trace:
 <IRQ>
 __sk_destruct+0x85/0xab0 net/core/sock.c:2352
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869
 handle_softirqs+0x1ea/0xa00 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1061 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1061
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:pv_native_safe_halt+0xf/0x20 arch/x86/kernel/paravirt.c:63
Code: 56 92 02 e9 c3 42 03 00 0f 1f 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 63 51 20 00 fb f4 <c3> cc cc cc cc 66 2e 0f 1f 84 00 00 00 00 00 66 90 90 90 90 90 90
RSP: 0018:ffffffff8e407e00 EFLAGS: 00000202
RAX: 00000000000c0cf1 RBX: ffffffff8e4955c0 RCX: ffffffff8b8b4095
RDX: 0000000000000000 RSI: ffffffff8df23ea0 RDI: ffffffff8c1c4180
RBP: 0000000000000000 R08: 0000000000000001 R09: ffffed100d4867b5
R10: ffff88806a433dab R11: 0000000000000000 R12: 0000000000000000
R13: fffffbfff1c92ab8 R14: 0000000000000000 R15: ffffffff90d7e350
 arch_safe_halt arch/x86/include/asm/paravirt.h:62 [inline]
 default_idle+0x9/0x10 arch/x86/kernel/process.c:767
 default_idle_call+0x6c/0xb0 kernel/sched/idle.c:122
 cpuidle_idle_call kernel/sched/idle.c:199 [inline]
 do_idle+0x464/0x590 kernel/sched/idle.c:352
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:451
 rest_init+0x251/0x260 init/main.c:762
 start_kernel+0x484/0x490 init/main.c:1220
 x86_64_start_reservations+0x24/0x30 arch/x86/kernel/head64.c:310
 x86_64_start_kernel+0x12b/0x130 arch/x86/kernel/head64.c:291
 common_startup_64+0x13e/0x148
 </TASK>
----------------
Code disassembly (best guess):
   0:	56                   	push   %rsi
   1:	92                   	xchg   %eax,%edx
   2:	02 e9                	add    %cl,%ch
   4:	c3                   	ret
   5:	42 03 00             	rex.X add (%rax),%eax
   8:	0f 1f 00             	nopl   (%rax)
   b:	90                   	nop
   c:	90                   	nop
   d:	90                   	nop
   e:	90                   	nop
   f:	90                   	nop
  10:	90                   	nop
  11:	90                   	nop
  12:	90                   	nop
  13:	90                   	nop
  14:	90                   	nop
  15:	90                   	nop
  16:	90                   	nop
  17:	90                   	nop
  18:	90                   	nop
  19:	90                   	nop
  1a:	90                   	nop
  1b:	f3 0f 1e fa          	endbr64
  1f:	eb 07                	jmp    0x28
  21:	0f 00 2d 63 51 20 00 	verw   0x205163(%rip)        # 0x20518b
  28:	fb                   	sti
  29:	f4                   	hlt
* 2a:	c3                   	ret <-- trapping instruction
  2b:	cc                   	int3
  2c:	cc                   	int3
  2d:	cc                   	int3
  2e:	cc                   	int3
  2f:	66 2e 0f 1f 84 00 00 	cs nopw 0x0(%rax,%rax,1)
  36:	00 00 00
  39:	66 90                	xchg   %ax,%ax
  3b:	90                   	nop
  3c:	90                   	nop
  3d:	90                   	nop
  3e:	90                   	nop
  3f:	90                   	nop