[syzbot] WARNING in wait_til_done

From: syzbot
Date: Mon Apr 25 2022 - 15:52:37 EST


Hello,

syzbot found the following issue on:

HEAD commit: 22da5264abf4 Merge tag '5.18-rc3-ksmbd-fixes' of git://git..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=123287c0f00000
kernel config: https://syzkaller.appspot.com/x/.config?x=71bf5c8488a4e33a
dashboard link: https://syzkaller.appspot.com/bug?extid=3562be49b8e09d424a6f
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
userspace arch: i386

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+3562be49b8e09d424a6f@xxxxxxxxxxxxxxxxxxxxxxxxx

------------[ cut here ]------------
WARNING: CPU: 2 PID: 379 at drivers/block/floppy.c:1000 schedule_bh drivers/block/floppy.c:1000 [inline]
WARNING: CPU: 2 PID: 379 at drivers/block/floppy.c:1000 wait_til_done+0x350/0x3c0 drivers/block/floppy.c:2019
Modules linked in:
CPU: 2 PID: 379 Comm: syz-executor.0 Not tainted 5.18.0-rc3-syzkaller-00235-g22da5264abf4 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014
RIP: 0010:schedule_bh drivers/block/floppy.c:1000 [inline]
RIP: 0010:wait_til_done+0x350/0x3c0 drivers/block/floppy.c:2019
Code: fc 41 83 fd 01 7e ac e8 0e 56 e7 fc 4c 89 e6 48 c7 c7 20 c0 8c 8c e8 5f 9b c8 fc e8 fa 55 e7 fc e9 c3 fd ff ff e8 f0 55 e7 fc <0f> 0b e9 4b fd ff ff e8 b4 e6 32 fd e9 0f fe ff ff e8 da 55 e7 fc
RSP: 0018:ffffc900282676f8 EFLAGS: 00010212
RAX: 0000000000000987 RBX: 1ffff9200504cedf RCX: ffffc90003771000
RDX: 0000000000040000 RSI: ffffffff8491daa0 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff8c8cbd87
R10: ffffffff8491d7e9 R11: 0000000000000000 R12: 0000000000000001
R13: ffffffff8491aab0 R14: 0000000000000000 R15: 0000000000000003
FS: 0000000000000000(0000) GS:ffff88802cc00000(0063) knlGS:00000000f7f92b40
CS: 0010 DS: 002b ES: 002b CR0: 0000000080050033
CR2: 0000000030e22000 CR3: 0000000019451000 CR4: 0000000000150ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
floppy_check_events+0x3d0/0x560 drivers/block/floppy.c:4079
disk_check_events+0xc2/0x420 block/disk-events.c:193
disk_clear_events block/disk-events.c:248 [inline]
bdev_check_media_change+0x12c/0x310 block/disk-events.c:279
floppy_open+0x75d/0xd70 drivers/block/floppy.c:4038
blkdev_get_whole+0x99/0x2d0 block/bdev.c:666
blkdev_get_by_dev.part.0+0x5d2/0xc80 block/bdev.c:816
blkdev_get_by_dev+0x6b/0x80 block/bdev.c:850
blkdev_open+0x13c/0x2c0 block/fops.c:498
do_dentry_open+0x4a1/0x11e0 fs/open.c:824
do_open fs/namei.c:3476 [inline]
path_openat+0x1c71/0x2910 fs/namei.c:3609
do_filp_open+0x1aa/0x400 fs/namei.c:3636
do_sys_openat2+0x16d/0x4c0 fs/open.c:1213
do_sys_open fs/open.c:1229 [inline]
__do_compat_sys_openat fs/open.c:1289 [inline]
__se_compat_sys_openat fs/open.c:1287 [inline]
__ia32_compat_sys_openat+0x13f/0x1f0 fs/open.c:1287
do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline]
__do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178
do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203
entry_SYSENTER_compat_after_hwframe+0x4d/0x5c
RIP: 0023:0xf7f97549
Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00
RSP: 002b:00000000f7f92170 EFLAGS: 00000286 ORIG_RAX: 0000000000000127
RAX: ffffffffffffffda RBX: 00000000ffffff9c RCX: 00000000f7f921c0
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000f6f36000
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
</TASK>
----------------
Code disassembly (best guess):
0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi
4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d
a: 10 06 adc %al,(%rsi)
c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi
10: 10 07 adc %al,(%rdi)
12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi
16: 10 08 adc %cl,(%rax)
18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi
1c: 00 00 add %al,(%rax)
1e: 00 00 add %al,(%rax)
20: 00 51 52 add %dl,0x52(%rcx)
23: 55 push %rbp
24: 89 e5 mov %esp,%ebp
26: 0f 34 sysenter
28: cd 80 int $0x80
* 2a: 5d pop %rbp <-- trapping instruction
2b: 5a pop %rdx
2c: 59 pop %rcx
2d: c3 retq
2e: 90 nop
2f: 90 nop
30: 90 nop
31: 90 nop
32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi
39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx.

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.