------------[ 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#3: udevd/5140
Modules linked in:
CPU: 3 UID: 0 PID: 5140 Comm: udevd 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 1a 86 fd f7 90 0f 0b 90 e9 35 fe ff ff e8 0c 86 fd f7 90 0f 0b 90 e9 c5 fe ff ff e8 fe 85 fd f7 90 <0f> 0b 90 e9 04 ff ff ff e8 f0 85 fd f7 90 0f 0b 90 e9 65 fe ff ff
RSP: 0018:ffffc900006f8d88 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffff8880567a4400 RCX: ffffffff8a0b29a7
RDX: ffff88802cca0000 RSI: ffffffff8a0b2aa2 RDI: ffff88802cca0000
RBP: 0000000000000090 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000090 R11: 0000000000000000 R12: ffff8880567a4400
R13: ffff8880567a4490 R14: ffffffff81ee353d R15: 0000000000000004
FS:  00007f29f0347880(0000) GS:ffff8880d666a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f04c47e8158 CR3: 0000000034130000 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:lock_is_held_type+0xf5/0x140 kernel/locking/lockdep.c:5945
Code: ff ff ff ff 65 0f c1 15 f1 85 80 08 83 fa 01 8b 44 24 04 75 2d 9c 5a 80 e6 02 75 47 41 f7 c5 00 02 00 00 74 01 fb 48 83 c4 08 <5b> 5d 41 5c 41 5d 41 5e 41 5f c3 cc cc cc cc e9 57 39 03 00 31 c0
RSP: 0018:ffffc9000615fcc8 EFLAGS: 00000282
RAX: 0000000000000001 RBX: ffffffff8e7e5620 RCX: 0000000000000001
RDX: 0000000000000046 RSI: ffffffff8defe91b RDI: ffffffff8c1c4180
RBP: ffff88802cca0000 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 00000000ffffffff
R13: 0000000000000246 R14: ffff88802cca0c08 R15: 0000000000000003
 kernfs_root+0x20e/0x2a0 fs/kernfs/kernfs-internal.h:75
 kernfs_active+0xb6/0x110 fs/kernfs/dir.c:40
 kernfs_dir_next_pos fs/kernfs/dir.c:1965 [inline]
 kernfs_fop_readdir+0x490/0xa00 fs/kernfs/dir.c:1990
 iterate_dir+0x296/0xae0 fs/readdir.c:110
 __do_sys_getdents64 fs/readdir.c:399 [inline]
 __se_sys_getdents64 fs/readdir.c:384 [inline]
 __x64_sys_getdents64+0x13b/0x2c0 fs/readdir.c:384
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x10b/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f29efcf0d23
Code: 8b 05 d9 00 10 00 64 c7 00 16 00 00 00 31 c0 eb b0 66 0f 1f 44 00 00 b8 ff ff ff 7f 48 39 c2 48 0f 47 d0 b8 d9 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 05 c3 0f 1f 40 00 48 8b 15 a1 00 10 00 f7 d8
RSP: 002b:00007fff26323ae8 EFLAGS: 00000293 ORIG_RAX: 00000000000000d9
RAX: ffffffffffffffda RBX: 000056328797e150 RCX: 00007f29efcf0d23
RDX: 0000000000008000 RSI: 000056328797e180 RDI: 000000000000000c
RBP: 000056328797e154 R08: 0000000000000802 R09: 0000000000000000
R10: 00007f29efdf2050 R11: 0000000000000293 R12: 000056328797e180
R13: fffffffffffffe68 R14: 0000000000000016 R15: 00007fff26323d50
 </TASK>
----------------
Code disassembly (best guess), 3 bytes skipped:
   0:	ff 65 0f             	jmp    *0xf(%rbp)
   3:	c1 15 f1 85 80 08 83 	rcll   $0x83,0x88085f1(%rip)        # 0x88085fb
   a:	fa                   	cli
   b:	01 8b 44 24 04 75    	add    %ecx,0x75042444(%rbx)
  11:	2d 9c 5a 80 e6       	sub    $0xe6805a9c,%eax
  16:	02 75 47             	add    0x47(%rbp),%dh
  19:	41 f7 c5 00 02 00 00 	test   $0x200,%r13d
  20:	74 01                	je     0x23
  22:	fb                   	sti
  23:	48 83 c4 08          	add    $0x8,%rsp
* 27:	5b                   	pop    %rbx <-- trapping instruction
  28:	5d                   	pop    %rbp
  29:	41 5c                	pop    %r12
  2b:	41 5d                	pop    %r13
  2d:	41 5e                	pop    %r14
  2f:	41 5f                	pop    %r15
  31:	c3                   	ret
  32:	cc                   	int3
  33:	cc                   	int3
  34:	cc                   	int3
  35:	cc                   	int3
  36:	e9 57 39 03 00       	jmp    0x33992
  3b:	31 c0                	xor    %eax,%eax