bridge0: port 2(bridge_slave_1) entered disabled state
bridge0: port 1(bridge_slave_0) entered disabled state
bridge0: entered promiscuous mode
bridge0: entered allmulticast mode
bridge0: port 2(bridge_slave_1) entered blocking state
bridge0: port 2(bridge_slave_1) entered forwarding state
bridge0: port 1(bridge_slave_0) entered blocking state
bridge0: port 1(bridge_slave_0) entered forwarding state
BUG: kernel NULL pointer dereference, address: 00000000000003d8
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 0 P4D 0 
Oops: Oops: 0002 [#1] SMP KASAN NOPTI
CPU: 0 UID: 0 PID: 5343 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
RIP: 0010:__outb arch/x86/include/asm/shared/io.h:22 [inline]
RIP: 0010:subdev_8255_io+0x64/0xb0 drivers/comedi/drivers/comedi_8255.c:47
Code: e8 11 8f f3 f8 49 81 c6 d0 01 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 d4 39 5b f9 01 eb 41 03 1e 44 89 f8 <89> 66 90 31 c0 eb 2d e8 e0 8e f3 f8 49 81 c6 d0 01 00 00 4c 89 f0
RSP: 0018:ffffc9000e83f9e8 EFLAGS: 00010202
RAX: 000000000000009b RBX: 000000000000216b RCX: 0000000000100000
RDX: ffffc900210b2000 RSI: 0000000000000448 RDI: 0000000000000449
RBP: 0000000000000003 R08: 0000000000002168 R09: 00000000ffffffff
R10: 000000000000000b R11: ffffffff88cd75d0 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888040ba29d0 R15: 000000000000009b
FS:  00007f40045736c0(0000) GS:ffff88808d416000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000003d8 CR3: 000000001ee47000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 subdev_8255_do_config drivers/comedi/drivers/comedi_8255.c:115 [inline]
 __subdev_8255_init drivers/comedi/drivers/comedi_8255.c:172 [inline]
 subdev_8255_io_init+0x27c/0x330 drivers/comedi/drivers/comedi_8255.c:192
 dev_8255_attach+0x991/0xe40 drivers/comedi/drivers/8255.c:82
 comedi_device_attach+0x51f/0x720 drivers/comedi/drivers.c:1069
 do_devconfig_ioctl drivers/comedi/comedi_fops.c:928 [inline]
 comedi_unlocked_ioctl+0x645/0x1020 drivers/comedi/comedi_fops.c:2240
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xec/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f400378f7c9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f4004573038 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f40039e5fa0 RCX: 00007f400378f7c9
RDX: 0000200000000140 RSI: 0000000040946400 RDI: 000000000000000a
RBP: 00007f4003813f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f40039e6038 R14: 00007f40039e5fa0 R15: 00007ffc587e4b48
 </TASK>
Modules linked in:
CR2: 00000000000003d8
---[ end trace 0000000000000000 ]---
RIP: 0010:__outb arch/x86/include/asm/shared/io.h:22 [inline]
RIP: 0010:subdev_8255_io+0x64/0xb0 drivers/comedi/drivers/comedi_8255.c:47
Code: e8 11 8f f3 f8 49 81 c6 d0 01 00 00 4c 89 f0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 f7 e8 d4 39 5b f9 01 eb 41 03 1e 44 89 f8 <89> 66 90 31 c0 eb 2d e8 e0 8e f3 f8 49 81 c6 d0 01 00 00 4c 89 f0
RSP: 0018:ffffc9000e83f9e8 EFLAGS: 00010202
RAX: 000000000000009b RBX: 000000000000216b RCX: 0000000000100000
RDX: ffffc900210b2000 RSI: 0000000000000448 RDI: 0000000000000449
RBP: 0000000000000003 R08: 0000000000002168 R09: 00000000ffffffff
R10: 000000000000000b R11: ffffffff88cd75d0 R12: 0000000000000001
R13: dffffc0000000000 R14: ffff888040ba29d0 R15: 000000000000009b
FS:  00007f40045736c0(0000) GS:ffff88808d416000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00000000000003d8 CR3: 000000001ee47000 CR4: 0000000000352ef0
----------------
Code disassembly (best guess):
   0:	e8 11 8f f3 f8       	call   0xf8f38f16
   5:	49 81 c6 d0 01 00 00 	add    $0x1d0,%r14
   c:	4c 89 f0             	mov    %r14,%rax
   f:	48 c1 e8 03          	shr    $0x3,%rax
  13:	42 80 3c 28 00       	cmpb   $0x0,(%rax,%r13,1)
  18:	74 08                	je     0x22
  1a:	4c 89 f7             	mov    %r14,%rdi
  1d:	e8 d4 39 5b f9       	call   0xf95b39f6
  22:	01 eb                	add    %ebp,%ebx
  24:	41 03 1e             	add    (%r14),%ebx
  27:	44 89 f8             	mov    %r15d,%eax
* 2a:	89 66 90             	mov    %esp,-0x70(%rsi) <-- trapping instruction
  2d:	31 c0                	xor    %eax,%eax
  2f:	eb 2d                	jmp    0x5e
  31:	e8 e0 8e f3 f8       	call   0xf8f38f16
  36:	49 81 c6 d0 01 00 00 	add    $0x1d0,%r14
  3d:	4c 89 f0             	mov    %r14,%rax