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Date:   Tue, 16 Mar 2021 09:24:21 +0000
From:   Russell King - ARM Linux admin <linux@armlinux.org.uk>
To:     Dmitry Vyukov <dvyukov@google.com>
Cc:     syzbot <syzbot+0b06ef9b44d00d600183@syzkaller.appspotmail.com>,
        Arnd Bergmann <arnd@arndb.de>,
        Linus Walleij <linus.walleij@linaro.org>,
        Linux ARM <linux-arm-kernel@lists.infradead.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        LKML <linux-kernel@vger.kernel.org>,
        Linux-MM <linux-mm@kvack.org>,
        syzkaller-bugs <syzkaller-bugs@googlegroups.com>
Subject: Re: [syzbot] kernel panic: corrupted stack end in openat
Message-ID: <20210316092420.GN1463@shell.armlinux.org.uk>
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Sender: Russell King - ARM Linux admin <linux@armlinux.org.uk>
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On Tue, Mar 16, 2021 at 08:59:17AM +0100, Dmitry Vyukov wrote:
> On Tue, Mar 16, 2021 at 8:18 AM syzbot
> <syzbot+0b06ef9b44d00d600183@syzkaller.appspotmail.com> wrote:
> >
> > Hello,
> >
> > syzbot found the following issue on:
> >
> > HEAD commit:    1e28eed1 Linux 5.12-rc3
> > git tree:       upstream
> > console output: https://syzkaller.appspot.com/x/log.txt?x=167535e6d00000
> > kernel config:  https://syzkaller.appspot.com/x/.config?x=e0cee1f53de33ca3
> > dashboard link: https://syzkaller.appspot.com/bug?extid=0b06ef9b44d00d600183
> > userspace arch: arm
> >
> > Unfortunately, I don't have any reproducer for this issue yet.
> >
> > IMPORTANT: if you fix the issue, please add the following tag to the commit:
> > Reported-by: syzbot+0b06ef9b44d00d600183@syzkaller.appspotmail.com
> 
> +arm32 maintainer
> I think this is a real stack overflow on arm32, the stack is indeed deep.

There's no way to know for sure because there's no indication of the
stack pointer in this, so we don't know how much space remains.
Therefore we don't know whether this is something in the dumped
path, or an interrupt causing it.

-- 
RMK's Patch system: https://www.armlinux.org.uk/developer/patches/
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