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From:   Li Zhong <floridsleeves@gmail.com>
Date:   Sun, 28 Aug 2022 12:57:32 -0700
Message-ID: <CAMEuxRqBEMdva3qEphvuYkFLpRjp=xg7vpqQT1oqb2AgkkG2+w@mail.gmail.com>
Subject: Re: [PATCH v2] drivers/tty/serial: check the return value of uart_port_check()
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     "open list:SERIAL DRIVERS" <linux-serial@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jirislaby@kernel.org>
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On Fri, Aug 26, 2022 at 9:01 AM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
>
> On Fri, Aug 26, 2022 at 11:38 AM Li Zhong <floridsleeves@gmail.com> wrote:
> >
> > uart_port_check() will return NULL pointer when state->uart_port is
> > NULL. Check the return value before dereference it to avoid
> > null-pointer-dereference error.
>
> Have you taken the locking into consideration?
> If no, please do, if yes, expand your commit message to explain why
> the current locking scheme doesn't prevent an error from happening.
>

The locking is taken into consideration but these three checks do not need to
unlock in error-handling because unlock() will be called in the callers. Will
add the comment in v2 patch.

> --
> With Best Regards,
> Andy Shevchenko