Re: [syzbot] [block?] WARNING in floppy_revalidate

From: syzbot
Date: Sat Nov 11 2023 - 09:47:11 EST


Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
WARNING in floppy_revalidate

------------[ cut here ]------------
WARNING: CPU: 2 PID: 5371 at drivers/block/floppy.c:999 schedule_bh drivers/block/floppy.c:999 [inline]
WARNING: CPU: 2 PID: 5371 at drivers/block/floppy.c:999 process_fd_request drivers/block/floppy.c:2847 [inline]
WARNING: CPU: 2 PID: 5371 at drivers/block/floppy.c:999 floppy_revalidate.isra.0+0x911/0xca0 drivers/block/floppy.c:4214
Modules linked in:
CPU: 2 PID: 5371 Comm: syz-executor.0 Not tainted 6.6.0-syzkaller-16159-g3ca112b71f35 #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0010:schedule_bh drivers/block/floppy.c:999 [inline]
RIP: 0010:process_fd_request drivers/block/floppy.c:2847 [inline]
RIP: 0010:floppy_revalidate.isra.0+0x911/0xca0 drivers/block/floppy.c:4214
Code: 07 0f 86 d2 f7 ff ff 48 89 de 48 c7 c7 20 ca f8 8c e8 43 9b 81 ff e9 be f7 ff ff e8 59 4f 0e fd e9 77 fa ff ff e8 df 7a ba fc <0f> 0b e9 04 fb ff ff e8 d3 7a ba fc 48 83 fb 07 0f 87 58 03 00 00
RSP: 0018:ffffc9000383f8e8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000001 RCX: ffffffff84c93273
RDX: ffff888022140000 RSI: ffffffff84c93771 RDI: 0000000000000001
RBP: 0000000000000001 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000001
R13: ffff88801e762000 R14: 0000000000000050 R15: 0000000000000001
FS: 00007f2ea16386c0(0000) GS:ffff88806ba00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2ea0588000 CR3: 0000000017284000 CR4: 0000000000350ef0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<TASK>
floppy_open+0xa74/0xe00 drivers/block/floppy.c:4061
blkdev_get_whole+0x93/0x2c0 block/bdev.c:640
blkdev_get_by_dev.part.0+0x211/0xb20 block/bdev.c:795
blkdev_get_by_dev block/bdev.c:851 [inline]
bdev_open_by_dev+0x166/0x1c0 block/bdev.c:840
blkdev_open+0xe6/0x390 block/fops.c:600
do_dentry_open+0x8d4/0x18d0 fs/open.c:948
do_open fs/namei.c:3622 [inline]
path_openat+0x1d26/0x2c20 fs/namei.c:3779
do_filp_open+0x1cb/0x410 fs/namei.c:3809
do_sys_openat2+0x15c/0x1c0 fs/open.c:1440
do_sys_open fs/open.c:1455 [inline]
__do_sys_openat fs/open.c:1471 [inline]
__se_sys_openat fs/open.c:1466 [inline]
__x64_sys_openat+0x175/0x210 fs/open.c:1466
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0xe0 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7f2ea0478640
Code: 48 89 44 24 20 75 93 44 89 54 24 0c e8 09 7e 02 00 44 8b 54 24 0c 89 da 48 89 ee 41 89 c0 bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 77 38 44 89 c7 89 44 24 0c e8 5c 7e 02 00 8b 44
RSP: 002b:00007f2ea1637c00 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f2ea0478640
RDX: 0000000000000000 RSI: 00007f2ea1637ca0 RDI: 00000000ffffff9c
RBP: 00007f2ea1637ca0 R08: 0000000000000000 R09: 002364662f766564
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 000000000000000b R14: 00007f2ea058bf60 R15: 00007ffef761ff28
</TASK>


Tested on:

commit: 3ca112b7 Merge tag 'probes-fixes-v6.7-rc1' of git://gi..
git tree: https://kernel.googlesource.com/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=1491ec2f680000
kernel config: https://syzkaller.appspot.com/x/.config?x=44a532e1ba684f13
dashboard link: https://syzkaller.appspot.com/bug?extid=c5732f0517748c2c8051
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.