[syzbot] Monthly btrfs report (Feb 2024)

[syzbot] Monthly btrfs report (Feb 2024)

[syzbot]

Hello btrfs maintainers/developers,

This is a 31-day syzbot report for the btrfs subsystem.
All related reports/information can be found at:
https://syzkaller.appspot.com/upstream/s/btrfs

During the period, 1 new issues were detected and 1 were fixed.
In total, 43 issues are still open and 51 have been fixed so far.

Some of the still happening issues:

Ref  Crashes Repro Title
<1>  5804    Yes   kernel BUG in close_ctree
                   https://syzkaller.appspot.com/bug?extid=2665d678fffcc4608e18
<2>  2636    Yes   WARNING in btrfs_space_info_update_bytes_may_use
                   https://syzkaller.appspot.com/bug?extid=8edfa01e46fd9fe3fbfb
<3>  251     Yes   INFO: task hung in lock_extent
                   https://syzkaller.appspot.com/bug?extid=eaa05fbc7563874b7ad2
<4>  245     Yes   WARNING in btrfs_chunk_alloc
                   https://syzkaller.appspot.com/bug?extid=e8e56d5d31d38b5b47e7
<5>  224     Yes   WARNING in btrfs_remove_chunk
                   https://syzkaller.appspot.com/bug?extid=e8582cc16881ec70a430
<6>  125     Yes   kernel BUG in insert_state_fast
                   https://syzkaller.appspot.com/bug?extid=9ce4a36127ca92b59677
<7>  99      Yes   kernel BUG in btrfs_free_tree_block
                   https://syzkaller.appspot.com/bug?extid=a306f914b4d01b3958fe
<8>  88      Yes   kernel BUG in set_state_bits
                   https://syzkaller.appspot.com/bug?extid=b9d2e54d2301324657ed
<9>  79      Yes   WARNING in btrfs_commit_transaction (2)
                   https://syzkaller.appspot.com/bug?extid=dafbca0e20fbc5946925
<10> 74      Yes   WARNING in btrfs_put_transaction
                   https://syzkaller.appspot.com/bug?extid=3706b1df47f2464f0c1e

---
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@googlegroups.com.

To disable reminders for individual bugs, reply with the following command:
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Re: [syzbot] Monthly btrfs report (Feb 2024)

[Qu Wenruo]

On 2024/2/10 07:27, syzbot wrote:
> Hello btrfs maintainers/developers,
>
> This is a 31-day syzbot report for the btrfs subsystem.
> All related reports/information can be found at:
> https://syzkaller.appspot.com/upstream/s/btrfs
>
> During the period, 1 new issues were detected and 1 were fixed.
> In total, 43 issues are still open and 51 have been fixed so far.
>
> Some of the still happening issues:
>
> Ref  Crashes Repro Title
> <1>  5804    Yes   kernel BUG in close_ctree
>                     https://syzkaller.appspot.com/bug?extid=2665d678fffcc4608e18

I'm not sure why, but I never had a good experience reproducing the bug
using the C reproduer.

Furthermore, for this particular case, using that C reproducer only
reduced tons of duplicated dmesg of:

[  162.264838] btrfs: Unknown parameter 'noinode_cache'
[  162.308573] loop0: detected capacity change from 0 to 32768
[  162.308964] btrfs: Unknown parameter 'noinode_cache'
[  162.313582] loop1: detected capacity change from 0 to 32768
[  162.314070] btrfs: Unknown parameter 'noinode_cache'
[  162.323629] loop3: detected capacity change from 0 to 32768
[  162.324000] btrfs: Unknown parameter 'noinode_cache'
[  162.328046] loop2: detected capacity change from 0 to 32768
[  162.328417] btrfs: Unknown parameter 'noinode_cache'

Unlike the latest report which shows a lot of other things.

Anyone can help verifying the C reproducer?
Or I'm doing something wrong withe the reproducer?

Thanks,
Qu
> <2>  2636    Yes   WARNING in btrfs_space_info_update_bytes_may_use
>                     https://syzkaller.appspot.com/bug?extid=8edfa01e46fd9fe3fbfb
> <3>  251     Yes   INFO: task hung in lock_extent
>                     https://syzkaller.appspot.com/bug?extid=eaa05fbc7563874b7ad2
> <4>  245     Yes   WARNING in btrfs_chunk_alloc
>                     https://syzkaller.appspot.com/bug?extid=e8e56d5d31d38b5b47e7
> <5>  224     Yes   WARNING in btrfs_remove_chunk
>                     https://syzkaller.appspot.com/bug?extid=e8582cc16881ec70a430
> <6>  125     Yes   kernel BUG in insert_state_fast
>                     https://syzkaller.appspot.com/bug?extid=9ce4a36127ca92b59677
> <7>  99      Yes   kernel BUG in btrfs_free_tree_block
>                     https://syzkaller.appspot.com/bug?extid=a306f914b4d01b3958fe
> <8>  88      Yes   kernel BUG in set_state_bits
>                     https://syzkaller.appspot.com/bug?extid=b9d2e54d2301324657ed
> <9>  79      Yes   WARNING in btrfs_commit_transaction (2)
>                     https://syzkaller.appspot.com/bug?extid=dafbca0e20fbc5946925
> <10> 74      Yes   WARNING in btrfs_put_transaction
>                     https://syzkaller.appspot.com/bug?extid=3706b1df47f2464f0c1e
>
> ---
> 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@googlegroups.com.
>
> To disable reminders for individual bugs, reply with the following command:
> #syz set <Ref> no-reminders
>
> To change bug's subsystems, reply with:
> #syz set <Ref> subsystems: new-subsystem
>
> You may send multiple commands in a single email message.
>

Re: [syzbot] Monthly btrfs report (Feb 2024)

[Aleksandr Nogikh]

Hi,

It looks like existing reproducers for this bug began to fail after
CONFIG_BLK_DEV_WRITE_MOUNTED reached torvalds and syzbot has not found
a newer reproducer since then (though it does hit the bug, so it must
be possible even with CONFIG_BLK_DEV_WRITE_MOUNTED=n).

I was was able to reproduce it locally using the older kernel revision
built by syzbot:
https://gist.github.com/a-nogikh/f68aa687a72aad4bb46a64d995c2415f
FWIW here are the docs:
https://github.com/google/syzkaller/blob/master/docs/syzbot_assets.md

-- 
Aleksandr

On Sat, Feb 10, 2024 at 9:48 AM 'Qu Wenruo' via syzkaller-bugs
<syzkaller-bugs@googlegroups.com> wrote:
>
> >
> > Ref  Crashes Repro Title
> > <1>  5804    Yes   kernel BUG in close_ctree
> >                     https://syzkaller.appspot.com/bug?extid=2665d678fffcc4608e18
>
> I'm not sure why, but I never had a good experience reproducing the bug
> using the C reproduer.
>
> Furthermore, for this particular case, using that C reproducer only
> reduced tons of duplicated dmesg of:
>
> [  162.264838] btrfs: Unknown parameter 'noinode_cache'
> [  162.308573] loop0: detected capacity change from 0 to 32768
> [  162.308964] btrfs: Unknown parameter 'noinode_cache'
> [  162.313582] loop1: detected capacity change from 0 to 32768
> [  162.314070] btrfs: Unknown parameter 'noinode_cache'
> [  162.323629] loop3: detected capacity change from 0 to 32768
> [  162.324000] btrfs: Unknown parameter 'noinode_cache'
> [  162.328046] loop2: detected capacity change from 0 to 32768
> [  162.328417] btrfs: Unknown parameter 'noinode_cache'
>
> Unlike the latest report which shows a lot of other things.
>
> Anyone can help verifying the C reproducer?
> Or I'm doing something wrong withe the reproducer?
>
> Thanks,
> Qu
> > <2>  2636    Yes   WARNING in btrfs_space_info_update_bytes_may_use
> >                     https://syzkaller.appspot.com/bug?extid=8edfa01e46fd9fe3fbfb
> > <3>  251     Yes   INFO: task hung in lock_extent
> >                     https://syzkaller.appspot.com/bug?extid=eaa05fbc7563874b7ad2
> > <4>  245     Yes   WARNING in btrfs_chunk_alloc
> >                     https://syzkaller.appspot.com/bug?extid=e8e56d5d31d38b5b47e7
> > <5>  224     Yes   WARNING in btrfs_remove_chunk
> >                     https://syzkaller.appspot.com/bug?extid=e8582cc16881ec70a430
> > <6>  125     Yes   kernel BUG in insert_state_fast
> >                     https://syzkaller.appspot.com/bug?extid=9ce4a36127ca92b59677
> > <7>  99      Yes   kernel BUG in btrfs_free_tree_block
> >                     https://syzkaller.appspot.com/bug?extid=a306f914b4d01b3958fe
> > <8>  88      Yes   kernel BUG in set_state_bits
> >                     https://syzkaller.appspot.com/bug?extid=b9d2e54d2301324657ed
> > <9>  79      Yes   WARNING in btrfs_commit_transaction (2)
> >                     https://syzkaller.appspot.com/bug?extid=dafbca0e20fbc5946925
> > <10> 74      Yes   WARNING in btrfs_put_transaction
> >                     https://syzkaller.appspot.com/bug?extid=3706b1df47f2464f0c1e
> >
> > ---
> > 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@googlegroups.com.
> >
> > To disable reminders for individual bugs, reply with the following command:
> > #syz set <Ref> no-reminders
> >
> > To change bug's subsystems, reply with:
> > #syz set <Ref> subsystems: new-subsystem
> >
> > You may send multiple commands in a single email message.
> >
>