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From:   "Starke, Daniel" <daniel.starke@siemens.com>
To:     Jiri Slaby <jirislaby@kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>
CC:     Lee Jones <lee@kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Fedor Pchelkin <pchelkin@ispras.ru>,
        "linux-serial@vger.kernel.org" <linux-serial@vger.kernel.org>,
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        <syzbot+5f47a8cea6a12b77a876@syzkaller.appspotmail.com>
Subject: RE: [PATCH 1/1] tty: n_gsm: Avoid sleeping during .write() whilst
 atomic
Thread-Topic: [PATCH 1/1] tty: n_gsm: Avoid sleeping during .write() whilst
 atomic
Thread-Index: AQHZ9hsms1Jp2Ee+x0K6pi4iDpsHIrA4XssAgADExJCAAC0rHYAABPWw
Date:   Wed, 4 Oct 2023 08:58:32 +0000
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References: <20231003170020.830242-1-lee@kernel.org>
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> So without actually looking into the code, can we just somehow disallow
> attaching this line discipline to a console (ban such a TIOCSETD) and be
> done with this issue? IOW disallow root to shoot their foot.

Probably possible by patching gsmld_open() if there is a function which can
check this based on a struct tty_struct * handle. That may, however,
introduce some cross references that are hard to maintain.

Best regards,
Daniel Starke