[syzbot] general protection fault in line6_midibuf_write (2)

[syzbot <syzbot+0d2b3feb0a2887862e06@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    e5242861 usb: gadget: s3c: Fix the error handling path in ..
git tree:       https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing
console output: https://syzkaller.appspot.com/x/log.txt?x=15dd2111d00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=9f35f6ae509ee286
dashboard link: https://syzkaller.appspot.com/bug?extid=0d2b3feb0a2887862e06

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0d2b3feb0a2887862e06@syzkaller.appspotmail.com

general protection fault, probably for non-canonical address 0xdffffc0000000019: 0000 [#1] SMP KASAN
KASAN: null-ptr-deref in range [0x00000000000000c8-0x00000000000000cf]
CPU: 0 PID: 27882 Comm: syz-executor.1 Not tainted 5.12.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:midibuf_is_full sound/usb/line6/midibuf.c:44 [inline]
RIP: 0010:line6_midibuf_write+0x30/0x3f0 sound/usb/line6/midibuf.c:91
Code: 49 89 f5 41 54 55 89 d5 53 48 89 fb 4c 8d 7b 18 48 83 ec 28 e8 a1 12 95 fc 4c 89 fa 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 09 03 00 00 44 8b 63 18 31 ff
RSP: 0018:ffffc900000079f0 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 00000000000000b0 RCX: ffffc900055a9000
RDX: 0000000000000019 RSI: ffffffff84ab519f RDI: 00000000000000b0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff87ac9e83
R10: ffffffff84ab1930 R11: 0000000000000001 R12: 00000000000000b0
R13: ffff88811544da80 R14: ffff8881161ca584 R15: 00000000000000c8
FS:  00007fe616b12700(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fef908ea130 CR3: 000000010da07000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <IRQ>
 line6_data_received+0x281/0x520 sound/usb/line6/driver.c:296
 __usb_hcd_giveback_urb+0x2b0/0x5c0 drivers/usb/core/hcd.c:1656
 usb_hcd_giveback_urb+0x367/0x410 drivers/usb/core/hcd.c:1726
 dummy_timer+0x11f4/0x32a0 drivers/usb/gadget/udc/dummy_hcd.c:1971
 call_timer_fn+0x1a5/0x630 kernel/time/timer.c:1431
 expire_timers kernel/time/timer.c:1476 [inline]
 __run_timers.part.0+0x67c/0xa10 kernel/time/timer.c:1745
 __run_timers kernel/time/timer.c:1726 [inline]
 run_timer_softirq+0x80/0x120 kernel/time/timer.c:1758
 __do_softirq+0x1b0/0x944 kernel/softirq.c:345
 invoke_softirq kernel/softirq.c:221 [inline]
 __irq_exit_rcu kernel/softirq.c:422 [inline]
 irq_exit_rcu+0x110/0x1a0 kernel/softirq.c:434
 sysvec_apic_timer_interrupt+0x6a/0x90 arch/x86/kernel/apic/apic.c:1100
 </IRQ>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:632
RIP: 0010:_raw_spin_unlock_irqrestore+0x3a/0x50 kernel/locking/spinlock.c:192
Code: 10 e8 6a 0c 76 fb 48 89 ef e8 32 c0 76 fb 81 e3 00 02 00 00 75 17 9c 58 f6 c4 02 75 17 48 85 db 74 01 fb 65 ff 0d 96 a5 50 7a <5b> 5d c3 e8 5e f2 94 fb eb e2 e8 b7 85 fe ff eb e2 0f 1f 44 00 00
RSP: 0018:ffffc900148ffe18 EFLAGS: 00000246
RAX: 0000000000000006 RBX: 0000000000000200 RCX: 1ffffffff11996b1
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff85b14972
RBP: ffff8881068a4008 R08: 0000000000000001 R09: 0000000000000001
R10: ffffffff81463c08 R11: 0000000000000000 R12: 0000000000000216
R13: ffff8881068a4008 R14: fffffffffffffff0 R15: 1ffff9200291ffcf
 spin_unlock_irqrestore include/linux/spinlock.h:409 [inline]
 raw_ioctl_ep0_stall drivers/usb/gadget/legacy/raw_gadget.c:751 [inline]
 raw_ioctl+0xed8/0x2720 drivers/usb/gadget/legacy/raw_gadget.c:1247
 vfs_ioctl fs/ioctl.c:48 [inline]
 __do_sys_ioctl fs/ioctl.c:753 [inline]
 __se_sys_ioctl fs/ioctl.c:739 [inline]
 __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:739
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x466217
Code: 3c 1c 48 f7 d8 49 39 c4 72 b8 e8 a4 48 02 00 85 c0 78 bd 48 83 c4 08 4c 89 e0 5b 41 5c c3 0f 1f 44 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fe616b100b8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007fe616b11130 RCX: 0000000000466217
RDX: 0000000000000000 RSI: 0000000000005501 RDI: 0000000000000005
RBP: 0000000000000005 R08: 0000000000000010 R09: 00312e6364755f79
R10: 00007fe616b0fe57 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000020000000 R15: 00000000000010d0
Modules linked in:
---[ end trace 71f0ad4466d7d24b ]---
RIP: 0010:midibuf_is_full sound/usb/line6/midibuf.c:44 [inline]
RIP: 0010:line6_midibuf_write+0x30/0x3f0 sound/usb/line6/midibuf.c:91
Code: 49 89 f5 41 54 55 89 d5 53 48 89 fb 4c 8d 7b 18 48 83 ec 28 e8 a1 12 95 fc 4c 89 fa 48 b8 00 00 00 00 00 fc ff df 48 c1 ea 03 <0f> b6 04 02 84 c0 74 08 3c 03 0f 8e 09 03 00 00 44 8b 63 18 31 ff
RSP: 0018:ffffc900000079f0 EFLAGS: 00010002
RAX: dffffc0000000000 RBX: 00000000000000b0 RCX: ffffc900055a9000
RDX: 0000000000000019 RSI: ffffffff84ab519f RDI: 00000000000000b0
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff87ac9e83
R10: ffffffff84ab1930 R11: 0000000000000001 R12: 00000000000000b0
R13: ffff88811544da80 R14: ffff8881161ca584 R15: 00000000000000c8
FS:  00007fe616b12700(0000) GS:ffff8881f6a00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fef908ea130 CR3: 000000010da07000 CR4: 00000000001506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400


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