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Date: Tue, 7 Nov 2017 17:18:35 +0000
From: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
To: Eric Biggers <ebiggers3@gmail.com>
Cc: Greg KH <gregkh@linuxfoundation.org>,
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Subject: Re: kernel panic: n_tty: init_tty
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> It's not just running at boot though.  It's also being hit by the fuzzer at
> runtime, via ptmx_open().

Then modify the routine to try N_NULL as a follow up (see
tty_ldisc_restore). N_NULL will never fail.

Alan