Re: [syzbot] [mm?] BUG: corrupted list in add_to_unbuddied

[Aleksandr Nogikh <nogikh@google.com>]

On Wed, Oct 16, 2024 at 11:37 PM Andrew Morton
<akpm@linux-foundation.org> wrote:
>
> On Wed, 16 Oct 2024 08:19:25 +0200 Aleksandr Nogikh <nogikh@google.com> wrote:
>
> > Hi Andrew,
> >
> > On Wed, Oct 16, 2024 at 12:40 AM Andrew Morton
> > <akpm@linux-foundation.org> wrote:
> > >
> > > On Tue, 15 Oct 2024 07:52:25 -0700 syzbot <syzbot+30eac43568e2b3d65728@syzkaller.appspotmail.com> wrote:
> > >
> > > > syzbot has found a reproducer for the following issue on:
> > > >
> > > > HEAD commit:    eca631b8fe80 Merge tag 'f2fs-6.12-rc4' of git://git.kernel..
> > > > git tree:       upstream
> > > > console output: https://syzkaller.appspot.com/x/log.txt?x=14d0845f980000
> > > > kernel config:  https://syzkaller.appspot.com/x/.config?x=cfbd94c114a3d407
> > > > dashboard link: https://syzkaller.appspot.com/bug?extid=30eac43568e2b3d65728
> > > > compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
> > > > syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=16df4c40580000
> > >
> > > Something seems rather wrong with the "syz repro" page.
> > >
> > >
> >
> > What exactly looks wrong? :)
>

Hi Andrew,

That is not garbage :)
That's the compressed disk image that is mounted by the reproducer.
These images are often also mutated/corrupted and therefore unique in
each case, so we have no other option than to keep them in the
reproducer. If you scroll the file to the bottom, you'll see the other
syscalls that are part of it.

> I click on the link
> (https://syzkaller.appspot.com/x/repro.syz?x=16df4c40580000) and I get
> the below garbage:

-- 
Aleksandr

>
> > >
> > > # https://syzkaller.appspot.com/bug?id=6b5f76b3a3783e6b1876d25b2d7a981ac0e0131f
> > > # See https://goo.gl/kgGztJ for information about syzkaller reproducers.
> > > #{"threaded":true,"repeat":true,"procs":6,"slowdown":1,"sandbox":"none","sandbox_arg":0,"tun":true,"netdev":true,"resetnet":true,"cgroups":true,"binfmt_misc":true,"close_fds":true,"usb":true,"vhci":true,"wifi":true,"ieee802154":true,"sysctl":true,"swap":true,"tmpdir":true,"segv":true}
> > > syz_mount_image$ntfs3(&(0x7f0000000000), &(0x7f0000000140)='./bus\x00', 0x19c6038, &(0x7f0000000180)=ANY=[], 0x1, 0x1f231, &(0x7f000003e780)="$eJzs3QmYTeUfB/D37Pu+XLvBWEO2RLLvsm+pZAvZyRalGhJRSSWpFElCQqhUEklEsi8JSZKQVEIS/2fu3JlmufOvadf7/TyPOfeee877nnu+94z5ne0ebz25edsGbRISEhKIzZAU50gGSSSJXIq9xsfGXYoNmdi/EZ3nV9ttftQreZxZcOVtoxYUXjVUa7/MfEsim+xOx09VOLwp3JT7+MW2vXoPSeg9JGHAwKEJXRO6DRw4tGu3fj0Suvce0rdsQst+PboO6ZHQe8CQHoMzvNyz38BBg0YmdB3Q3VAHDe4xZEhC1wEjE/r2GJkwdGDC0MEjE7re2rX3gISyZcsmGCqB36jd/H96CQAAAAAAAAAAAAAAAAAA4M9x6VLaoX0AAAAAAAAAAAAAAAAAAAC4TDVo3LR+OaKkPWcIQxoRhsxlCCH2L9OlXvfPZdNO8qRdoo9yRX82Sn10um/5fuf
> > > <and a huge amount more>
> > >
>