[syzbot] general protection fault in reset_interrupt

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    c5c17547b778 Merge tag 'net-5.16-rc3' of git://git.kernel...
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16d12e9ab00000
kernel config:  https://syzkaller.appspot.com/x/.config?x=bf85c53718a1e697
dashboard link: https://syzkaller.appspot.com/bug?extid=b1f15b24307fd6df6021
compiler:       gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

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+b1f15b24307fd6df6021@xxxxxxxxxxxxxxxxxxxxxxxxx

floppy1: disk absent or changed during operation
floppy1: disk absent or changed during operation
floppy1: disk absent or changed during operation
floppy1: disk absent or changed during operation
general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f]
CPU: 0 PID: 9 Comm: kworker/u16:0 Not tainted 5.16.0-rc2-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
Workqueue: floppy floppy_work_workfn
RIP: 0010:reset_interrupt+0xef/0x140 drivers/block/floppy.c:1793
Code: fc 84 db 0f 85 ab 5e 9b 04 e8 5d 4f fc fc 48 8b 1d 76 4b 00 0c 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 08 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 40 48 8b 43 08 5b ff e0 e8 6f 85 42 fd eb a8 e8 68
RSP: 0018:ffffc900005cfd10 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff847a8383 RDI: 0000000000000008
RBP: ffffffff8c6a4240 R08: 0000000000000080 R09: 0000000000000000
R10: ffffffff847a8376 R11: 0000000000000000 R12: ffffc900005cfdb0
R13: ffffffff8c6a4250 R14: ffff888011850600 R15: ffff888010c75800
FS:  0000000000000000(0000) GS:ffff88802ca00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa679dac058 CR3: 00000000194aa000 CR4: 0000000000150ef0
DR0: 0000000000002000 DR1: 0000000000000000 DR2: 0000000000000001
DR3: 0000000000006000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
Modules linked in:
---[ end trace f0abc9321f84d854 ]---
RIP: 0010:reset_interrupt+0xef/0x140 drivers/block/floppy.c:1793
Code: fc 84 db 0f 85 ab 5e 9b 04 e8 5d 4f fc fc 48 8b 1d 76 4b 00 0c 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 08 48 89 fa 48 c1 ea 03 <80> 3c 02 00 75 40 48 8b 43 08 5b ff e0 e8 6f 85 42 fd eb a8 e8 68
RSP: 0018:ffffc900005cfd10 EFLAGS: 00010202
RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff847a8383 RDI: 0000000000000008
RBP: ffffffff8c6a4240 R08: 0000000000000080 R09: 0000000000000000
R10: ffffffff847a8376 R11: 0000000000000000 R12: ffffc900005cfdb0
R13: ffffffff8c6a4250 R14: ffff888011850600 R15: ffff888010c75800
FS:  0000000000000000(0000) GS:ffff88802cb00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2645abc6b8 CR3: 00000000194aa000 CR4: 0000000000150ee0
DR0: 0000000000002000 DR1: 0000000000000000 DR2: 0000000000000001
DR3: 0000000000006000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
   0:	fc                   	cld
   1:	84 db                	test   %bl,%bl
   3:	0f 85 ab 5e 9b 04    	jne    0x49b5eb4
   9:	e8 5d 4f fc fc       	callq  0xfcfc4f6b
   e:	48 8b 1d 76 4b 00 0c 	mov    0xc004b76(%rip),%rbx        # 0xc004b8b
  15:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax
  1c:	fc ff df
  1f:	48 8d 7b 08          	lea    0x8(%rbx),%rdi
  23:	48 89 fa             	mov    %rdi,%rdx
  26:	48 c1 ea 03          	shr    $0x3,%rdx
* 2a:	80 3c 02 00          	cmpb   $0x0,(%rdx,%rax,1) <-- trapping instruction
  2e:	75 40                	jne    0x70
  30:	48 8b 43 08          	mov    0x8(%rbx),%rax
  34:	5b                   	pop    %rbx
  35:	ff e0                	jmpq   *%rax
  37:	e8 6f 85 42 fd       	callq  0xfd4285ab
  3c:	eb a8                	jmp    0xffffffe6
  3e:	e8                   	.byte 0xe8
  3f:	68                   	.byte 0x68


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