general protection fault in __dev_printk

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit:    9a33b369 usb-fuzzer: main usb gadget fuzzer driver
git tree:       https://github.com/google/kasan/tree/usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=1014aacb200000
kernel config:  https://syzkaller.appspot.com/x/.config?x=23e37f59d94ddd15
dashboard link: https://syzkaller.appspot.com/bug?extid=2eb9121678bdb36e6d57
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1339c81d200000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+2eb9121678bdb36e6d57@xxxxxxxxxxxxxxxxxxxxxxxxx

usb 2-1: USB disconnect, device number 5
usb 1-1: New USB device strings: Mfr=0, Product=0, SerialNumber=0
yurex 2-1:0.150: yurex_interrupt - unknown status received: -71
kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory access
general protection fault: 0000 [#1] SMP KASAN PTI
CPU: 1 PID: 5497 Comm: kworker/u4:7 Not tainted 5.1.0-rc4-319354-g9a33b36 #3
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
RIP: 0010:dev_name include/linux/device.h:1087 [inline]
RIP: 0010:__dev_printk+0x3f/0x215 drivers/base/core.c:3208
Code: 89 f5 53 e8 6e fe 1b fc 48 85 ed 0f 84 c9 01 00 00 e8 60 fe 1b fc 48  
8d 7d 50 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 <80> 3c 02 00 74  
05 e8 11 0f 53 fc 4c 8b 7d 50 4d 85 ff 75 28 e8 33
RSP: 0018:ffff8880ad107970 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: ffffed1015a20f35 RCX: 00000000ffffffed
RDX: 0000000000000010 RSI: ffffffff8555c710 RDI: 0000000000000080
RBP: 0000000000000030 R08: ffff8880997ae200 R09: ffffed1015a24fc9
R10: ffffed1015a24fc8 R11: ffff8880ad127e47 R12: ffffffff8f031080
R13: ffff8880ad1079c8 R14: 0000000000000000 R15: ffff88809b373700
FS:  0000000000000000(0000) GS:ffff8880ad100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b5b78b000 CR3: 00000000a496c000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 _dev_err+0xdc/0x10e drivers/base/core.c:3251
 yurex_interrupt.cold+0x12e/0x13d drivers/usb/misc/yurex.c:183
 __usb_hcd_giveback_urb+0x1f4/0x470 drivers/usb/core/hcd.c:1758
 usb_hcd_giveback_urb+0x346/0x400 drivers/usb/core/hcd.c:1823
 dummy_timer+0x100b/0x32c0 drivers/usb/gadget/udc/dummy_hcd.c:1968
 call_timer_fn+0x161/0x5f0 kernel/time/timer.c:1325
 expire_timers kernel/time/timer.c:1362 [inline]
 __run_timers kernel/time/timer.c:1681 [inline]
 __run_timers kernel/time/timer.c:1649 [inline]
 run_timer_softirq+0x58b/0x1400 kernel/time/timer.c:1694
 __do_softirq+0x22a/0x8cd kernel/softirq.c:293
 do_softirq_own_stack+0x2a/0x40 arch/x86/entry/entry_64.S:1027
 </IRQ>
 do_softirq.part.0+0x60/0x70 kernel/softirq.c:338
 do_softirq kernel/softirq.c:330 [inline]
 __local_bh_enable_ip+0x183/0x1b0 kernel/softirq.c:190
 spin_unlock_bh include/linux/spinlock.h:374 [inline]
 batadv_nc_purge_paths+0x26b/0x380 net/batman-adv/network-coding.c:482
 batadv_nc_worker+0x2d4/0x770 net/batman-adv/network-coding.c:733
 process_one_work+0x90f/0x1580 kernel/workqueue.c:2269
 worker_thread+0x9b/0xe20 kernel/workqueue.c:2415
 kthread+0x313/0x420 kernel/kthread.c:253
 ret_from_fork+0x3a/0x50 arch/x86/entry/entry_64.S:352
Modules linked in:
---[ end trace 0f952022fa10fc7b ]---
RIP: 0010:dev_name include/linux/device.h:1087 [inline]
RIP: 0010:__dev_printk+0x3f/0x215 drivers/base/core.c:3208
Code: 89 f5 53 e8 6e fe 1b fc 48 85 ed 0f 84 c9 01 00 00 e8 60 fe 1b fc 48  
8d 7d 50 b8 ff ff 37 00 48 89 fa 48 c1 e0 2a 48 c1 ea 03 <80> 3c 02 00 74  
05 e8 11 0f 53 fc 4c 8b 7d 50 4d 85 ff 75 28 e8 33
RSP: 0018:ffff8880ad107970 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: ffffed1015a20f35 RCX: 00000000ffffffed
RDX: 0000000000000010 RSI: ffffffff8555c710 RDI: 0000000000000080
RBP: 0000000000000030 R08: ffff8880997ae200 R09: ffffed1015a24fc9
R10: ffffed1015a24fc8 R11: ffff8880ad127e47 R12: ffffffff8f031080
R13: ffff8880ad1079c8 R14: 0000000000000000 R15: ffff88809b373700
FS:  0000000000000000(0000) GS:ffff8880ad100000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f3b5b78b000 CR3: 00000000a496c000 CR4: 00000000001406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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