From: Gen Zhang <blackgod016574@gmail.com>
To: Johan Hovold <johan@kernel.org>
Cc: linux-kernel@vger.kernel.org
Subject: Re: [PATCH] tty_io: Fix a missing-check bug in drivers/tty/tty_io.c
Date: Wed, 22 May 2019 19:13:54 +0800 [thread overview]
Message-ID: <20190522111354.GA5849@zhanggen-UX430UQ> (raw)
In-Reply-To: <20190522102900.GC2200@localhost>
On Wed, May 22, 2019 at 12:29:00PM +0200, Johan Hovold wrote:
> Where do you see that the kernel is dereferencing tty->dev without
> checking for NULL first? If you can find that, then that would indeed be
> a bug that needs fixing.
Thanks for your reply, Johan!
I examined the code but failed to find this situation.
Anyway, checking return value of tty_get_device() is theoritically
right. But tty->dev is never dereferenced, so checking is not needed.
However, what if in later kernels tty->dev is dereferenced by some
codes? Is it better to apply this check for this reason?
Thanks
Gen
next prev parent reply other threads:[~2019-05-22 11:14 UTC|newest]
Thread overview: 10+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-05-22 1:40 [PATCH] tty_io: Fix a missing-check bug in drivers/tty/tty_io.c Gen Zhang
2019-05-22 4:25 ` Jiri Slaby
2019-05-22 8:06 ` Gen Zhang
2019-05-22 8:15 ` Jiri Slaby
2019-05-22 10:29 ` Johan Hovold
2019-05-22 10:32 ` Jiri Slaby
2019-05-22 11:13 ` Gen Zhang [this message]
2019-05-22 11:19 ` Johan Hovold
2019-05-22 11:24 ` Gen Zhang
2019-05-22 11:18 ` Gen Zhang
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