linux-kernel - Re: [syzbot] [mm?] WARNING: lock held when returning to user space in lock_next

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <CAJuCfpH=65SBkKiP88CwKPv-zGfTBCRgyHJU8Cz-0K2mKKrCpA@mail.gmail.com>
Date: Tue, 8 Jul 2025 17:05:24 -0700
From: Suren Baghdasaryan <surenb@...gle.com>
To: "Liam R. Howlett" <Liam.Howlett@...cle.com>, Suren Baghdasaryan <surenb@...gle.com>, 
	syzbot <syzbot+80011ad33eec39e6ce42@...kaller.appspotmail.com>, 
	akpm@...ux-foundation.org, linux-kernel@...r.kernel.org, linux-mm@...ck.org, 
	lorenzo.stoakes@...cle.com, shakeel.butt@...ux.dev, 
	syzkaller-bugs@...glegroups.com, vbabka@...e.cz
Subject: Re: [syzbot] [mm?] WARNING: lock held when returning to user space in lock_next_vma

On Tue, Jul 8, 2025 at 4:51 PM Suren Baghdasaryan <surenb@...gle.com> wrote:
>
> On Tue, Jul 8, 2025 at 4:15 PM Liam R. Howlett <Liam.Howlett@...cle.com> wrote:
> >
> > * Suren Baghdasaryan <surenb@...gle.com> [250708 18:19]:
> > > On Tue, Jul 8, 2025 at 10:52 AM syzbot
> > > <syzbot+80011ad33eec39e6ce42@...kaller.appspotmail.com> wrote:
> > > >
> > > > Hello,
> > > >
> > > > syzbot found the following issue on:
> > > >
> > > > HEAD commit:    26ffb3d6f02c Add linux-next specific files for 20250704
> > > > git tree:       linux-next
> > > > console output: https://syzkaller.appspot.com/x/log.txt?x=1719df70580000
> > > > kernel config:  https://syzkaller.appspot.com/x/.config?x=1e4f88512ae53408
> > > > dashboard link: https://syzkaller.appspot.com/bug?extid=80011ad33eec39e6ce42
> > > > compiler:       Debian clang version 20.1.7 (++20250616065708+6146a88f6049-1~exp1~20250616065826.132), Debian LLD 20.1.7
> > > > syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=1124abd4580000
> > > > C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=1099df70580000
> > > >
> > > > Downloadable assets:
> > > > disk image: https://storage.googleapis.com/syzbot-assets/fd5569903143/disk-26ffb3d6.raw.xz
> > > > vmlinux: https://storage.googleapis.com/syzbot-assets/1b0c9505c543/vmlinux-26ffb3d6.xz
> > > > kernel image: https://storage.googleapis.com/syzbot-assets/9d864c72bed1/bzImage-26ffb3d6.xz
> > > >
> > > > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > > > Reported-by: syzbot+80011ad33eec39e6ce42@...kaller.appspotmail.com
> > > >
> > > > ================================================
> > > > WARNING: lock held when returning to user space!
> > > > 6.16.0-rc4-next-20250704-syzkaller #0 Not tainted
> > > > ------------------------------------------------
> > > > syz.0.22/6068 is leaving the kernel with locks still held!
> > > > 1 lock held by syz.0.22/6068:
> > > >  #0: ffff8880792a3588 (vm_lock){++++}-{0:0}, at: lock_next_vma+0x146/0xdc0 mm/mmap_lock.c:220
> > >
> > > Hmm. I must be missing an unlock_vma() somewhere but I don't see it
> > > yet. Will try the reproducer.
> >
> > The last one was against v5 patches, is this v6?
>
> Oh, good point. Let me check that. Thanks!

You are probably right since the latest linux-next does not have my
patchset. So it must have been reported with the previous v5 version
of the patches.