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 <20230126131424.ufk6zspn6fyzw5l6@revolver>
In-Reply-To: <20230126131424.ufk6zspn6fyzw5l6@revolver>
From:   Dmitry Vyukov <dvyukov@google.com>
Date:   Fri, 27 Jan 2023 08:09:07 +0100
Message-ID: <CACT4Y+b3P8=0aehSvEhX09A5vTNFTaME1Qse93J-zCR6zns6HQ@mail.gmail.com>
Subject: Re: [syzbot] KASAN: use-after-free Read in mas_next_nentry
To:     "Liam R. Howlett" <Liam.Howlett@oracle.com>
Cc:     syzbot <syzbot+7170d66493145b71afd4@syzkaller.appspotmail.com>,
        brauner@kernel.org, dan.carpenter@oracle.com,
        linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org,
        syzkaller-bugs@googlegroups.com, torvalds@linux-foundation.org,
        viro@zeniv.linux.org.uk, wanjiabing@vivo.com, willy@infradead.org
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On Thu, 26 Jan 2023 at 14:14, Liam R. Howlett <Liam.Howlett@oracle.com> wrote:
>
> syz fix: fs/userfaultfd: Fix maple tree iterator in userfaultfd_unregister()
>
> * syzbot <syzbot+7170d66493145b71afd4@syzkaller.appspotmail.com> [230125 17:04]:
> > syzbot suspects this issue was fixed by commit:

syzbot needs the hash to parse the command:

#syz fix: fs/userfaultfd: Fix maple tree iterator in userfaultfd_unregister()

> > commit 59f2f4b8a757412fce372f6d0767bdb55da127a8
> > Author: Liam Howlett <liam.howlett@oracle.com>
> > Date:   Mon Nov 7 20:11:42 2022 +0000
> >
> >     fs/userfaultfd: Fix maple tree iterator in userfaultfd_unregister()
> >
> > bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=129e8afe480000
> > start commit:   b229b6ca5abb Merge tag 'perf-tools-fixes-for-v6.1-2022-10-..
> > git tree:       upstream
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=a66c6c673fb555e8
> > dashboard link: https://syzkaller.appspot.com/bug?extid=7170d66493145b71afd4
> > syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=11bfb2a9880000
> > C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=10b1d319880000
> >
> > If the result looks correct, please mark the issue as fixed by replying with:
> >
> > #syz fix: fs/userfaultfd: Fix maple tree iterator in userfaultfd_unregister()
> >
> > For information about bisection process see: https://goo.gl/tpsmEJ#bisection