------------[ cut here ]------------
sk->sk_forward_alloc
WARNING: net/ipv4/af_inet.c:163 at inet_sock_destruct+0x653/0x800 net/ipv4/af_inet.c:163, CPU#0: syz.6.19849/17539
Modules linked in:
CPU: 0 UID: 0 PID: 17539 Comm: syz.6.19849 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
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:163
Code: f1 4e ff e9 06 fd ff ff e8 1a 81 ff f7 90 0f 0b 90 e9 35 fe ff ff e8 0c 81 ff f7 90 0f 0b 90 e9 c5 fe ff ff e8 fe 80 ff f7 90 <0f> 0b 90 e9 04 ff ff ff e8 f0 80 ff f7 90 0f 0b 90 e9 65 fe ff ff
RSP: 0018:ffffc90000007d98 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff888040983300 RCX: ffffffff8a0973e7
RDX: ffff88802b4b24c0 RSI: ffffffff8a0974e2 RDI: ffff88802b4b24c0
RBP: 0000000000000090 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000090 R11: 0000000000000000 R12: ffff888040983300
R13: ffff888040983390 R14: ffffffff81eebb9d R15: 0000000000000002
FS:  00007f796b2ad6c0(0000) GS:ffff8880d633f000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009b60 CR3: 000000004c827000 CR4: 0000000000352ef0
DR0: ffffffffffffffff DR1: 00000000000001f8 DR2: 0000000000000083
DR3: ffffffffefffff15 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 __sk_destruct+0x85/0xbb0 net/core/sock.c:2350
 rcu_do_batch kernel/rcu/tree.c:2617 [inline]
 rcu_core+0x5a2/0x10d0 kernel/rcu/tree.c:2869
 handle_softirqs+0x1eb/0x9e0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0xef/0x150 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1056
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697
RIP: 0010:__raw_spin_unlock_irq include/linux/spinlock_api_smp.h:188 [inline]
RIP: 0010:_raw_spin_unlock_irq+0x29/0x50 kernel/locking/spinlock.c:202
Code: 90 f3 0f 1e fa 53 48 8b 74 24 08 48 89 fb 48 83 c7 18 e8 7a 8d 51 f6 48 89 df e8 62 dd 51 f6 e8 ad 73 7d f6 fb bf 01 00 00 00 <e8> 22 fe 41 f6 65 8b 05 cb 8e 7a 08 85 c0 74 06 5b c3 cc cc cc cc
RSP: 0018:ffffc9000503fc98 EFLAGS: 00000206
RAX: 0000000000052853 RBX: ffff88802d20ca00 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8de788fd RDI: 0000000000000001
RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000011
R13: ffff88802d20cc00 R14: dffffc0000000000 R15: ffff88802b4b24c0
 spin_unlock_irq include/linux/spinlock.h:401 [inline]
 get_signal+0x195a/0x21e0 kernel/signal.c:3037
 arch_do_signal_or_restart+0x91/0x7a0 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x86/0x4a0 kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline]
 do_syscall_64+0x67c/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f796a39c799
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f796b2ad0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: fffffffffffffe00 RBX: 00007f796a615fa8 RCX: 00007f796a39c799
RDX: 0000000000000000 RSI: 0000000000000080 RDI: 00007f796a615fa8
RBP: 00007f796a615fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f796a616038 R14: 00007ffc186384d0 R15: 00007ffc186385b8
 </TASK>
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	f3 0f 1e fa          	endbr64
   5:	53                   	push   %rbx
   6:	48 8b 74 24 08       	mov    0x8(%rsp),%rsi
   b:	48 89 fb             	mov    %rdi,%rbx
   e:	48 83 c7 18          	add    $0x18,%rdi
  12:	e8 7a 8d 51 f6       	call   0xf6518d91
  17:	48 89 df             	mov    %rbx,%rdi
  1a:	e8 62 dd 51 f6       	call   0xf651dd81
  1f:	e8 ad 73 7d f6       	call   0xf67d73d1
  24:	fb                   	sti
  25:	bf 01 00 00 00       	mov    $0x1,%edi
* 2a:	e8 22 fe 41 f6       	call   0xf641fe51 <-- trapping instruction
  2f:	65 8b 05 cb 8e 7a 08 	mov    %gs:0x87a8ecb(%rip),%eax        # 0x87a8f01
  36:	85 c0                	test   %eax,%eax
  38:	74 06                	je     0x40
  3a:	5b                   	pop    %rbx
  3b:	c3                   	ret
  3c:	cc                   	int3
  3d:	cc                   	int3
  3e:	cc                   	int3
  3f:	cc                   	int3