Re: WARNING in wdm_write/usb_submit_urb

[syzbot]

syzbot has found a reproducer for the following crash on:

HEAD commit:    e06ce4da usb-fuzzer: main usb gadget fuzzer driver
git tree:       https://github.com/google/kasan.git usb-fuzzer
console output: https://syzkaller.appspot.com/x/log.txt?x=14a8c0b6600000
kernel config:  https://syzkaller.appspot.com/x/.config?x=d0c62209eedfd54e
dashboard link: https://syzkaller.appspot.com/bug?extid=d232cca6ec42c2edb3fc
compiler:       gcc (GCC) 9.0.0 20181231 (experimental)
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=12b6dfba600000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=15f63a4c600000

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+d232cca6ec42c2edb3fc@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
URB 000000005fab893a submitted while active
WARNING: CPU: 1 PID: 1788 at drivers/usb/core/urb.c:362  
usb_submit_urb+0x10c1/0x13b0 drivers/usb/core/urb.c:362
Kernel panic - not syncing: panic_on_warn set ...
CPU: 1 PID: 1788 Comm: syz-executor522 Not tainted 5.3.0-rc5+ #27
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  
Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xca/0x13e lib/dump_stack.c:113
 panic+0x2a3/0x6da kernel/panic.c:219
 __warn.cold+0x20/0x4a kernel/panic.c:576
 report_bug+0x262/0x2a0 lib/bug.c:186
 fixup_bug arch/x86/kernel/traps.c:179 [inline]
 fixup_bug arch/x86/kernel/traps.c:174 [inline]
 do_error_trap+0x12b/0x1e0 arch/x86/kernel/traps.c:272
 do_invalid_op+0x32/0x40 arch/x86/kernel/traps.c:291
 invalid_op+0x23/0x30 arch/x86/entry/entry_64.S:1028
RIP: 0010:usb_submit_urb+0x10c1/0x13b0 drivers/usb/core/urb.c:362
Code: 89 de e8 82 bc ef fd 84 db 0f 85 42 f6 ff ff e8 45 bb ef fd 4c 89 fe  
48 c7 c7 80 68 18 86 c6 05 27 30 3a 04 01 e8 34 a1 c5 fd <0f> 0b e9 20 f6  
ff ff c7 44 24 14 01 00 00 00 e9 d7 f6 ff ff 41 bd
RSP: 0018:ffff8881d036fc98 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff81288cfd RDI: ffffed103a06df85
RBP: ffff8881cfce56a0 R08: ffff8881d1ce4800 R09: ffffed103b663ee7
R10: ffffed103b663ee6 R11: ffff8881db31f737 R12: 1ffff1103a06dfa7
R13: 00000000fffffff0 R14: ffff8881cfce5688 R15: ffff8881d8106d00
 wdm_write+0x828/0xd87 drivers/usb/class/cdc-wdm.c:423
 __vfs_write+0x76/0x100 fs/read_write.c:494
 vfs_write+0x262/0x5c0 fs/read_write.c:558
 ksys_write+0x127/0x250 fs/read_write.c:611
 do_syscall_64+0xb7/0x580 arch/x86/entry/common.c:296
 entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x447029
Code: e8 ec e7 ff ff 48 83 c4 18 c3 0f 1f 80 00 00 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 0f 83 3b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1e9e0a4da8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
RAX: ffffffffffffffda RBX: 00000000006dcc28 RCX: 0000000000447029
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000004
RBP: 00000000006dcc20 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dcc2c
R13: 0000000020000000 R14: 00000000004af170 R15: 00000000000003e8
Kernel Offset: disabled
Rebooting in 86400 seconds..