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From:   Hayes Wang <hayeswang@realtek.com>
To:     Alan Stern <stern@rowland.harvard.edu>
CC:     syzbot <syzbot+95afd23673f5dd295c57@syzkaller.appspotmail.com>,
        "davem@davemloft.net" <davem@davemloft.net>,
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Subject: RE: [syzbot] WARNING in rtl8152_probe
Thread-Topic: [syzbot] WARNING in rtl8152_probe
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Date:   Mon, 17 May 2021 01:01:28 +0000
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Alan Stern <stern@rowland.harvard.edu>
> Sent: Friday, May 14, 2021 11:33 PM
[...]
> The real motivation here, which nobody has mentioned explicitly yet, is
> that the driver needs to be careful enough that it won't crash no matter
> what bizarre, malfunctioning, or malicious device is attached.
> 
> Even if a device isn't malicious, if it is buggy, broken, or
> malfunctioning in some way then it can present input that a normal
> device would never generate.  If the driver isn't prepared to handle
> this unusual input, it may crash.  That is specifically what we want to
> avoid.
> 
> So if a peculiar emulated device created by syzbot is capable of
> crashing the driver, then somewhere there is a bug which needs to be
> fixed.  It's true that fixing all these bugs might not protect against a
> malicious device which deliberately behaves in an apparently reasonable
> manner.  But it does reduce the attack surface.

Thanks for your response.
I will add some checks.

Best Regards,
Hayes