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From:   Andy Shevchenko <andy.shevchenko@gmail.com>
Date:   Sat, 24 Jul 2021 23:21:04 +0300
Message-ID: <CAHp75Vd+ZM_yO6CU_6oJieePMt00Sp6oKEU2+QEyZxLDg5PN8A@mail.gmail.com>
Subject: Re: [PATCH v2 1/3] staging/fbtft: Remove all strcpy() uses
To:     Len Baker <len.baker@gmx.com>
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        Phil Reid <preid@electromag.com.au>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
        "open list:FRAMEBUFFER LAYER" <linux-fbdev@vger.kernel.org>,
        linux-staging@lists.linux.dev,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
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On Sat, Jul 24, 2021 at 7:05 PM Len Baker <len.baker@gmx.com> wrote:
>
> strcpy() performs no bounds checking on the destination buffer. This
> could result in linear overflows beyond the end of the buffer, leading
> to all kinds of misbehaviors. The safe replacement is strscpy() but in
> this case it is simpler to use the "%*ph" format specifier.

...

> -       char msg[128];

128 / 4 = 32. So, this buffer is enough to debug print only up to 32
bytes. Hence %*ph replacement won't cut output earlier than requested.

...

> +                       for (j = i + 1; par->init_sequence[j] >= 0; j++);

Why is i + 1 initial for the j? You may rather access the 'i + 1 +
j'th element in the array...

...

> +                                     par->init_sequence[i], j - i - 1,

...and get rid of the ' - i -1' part here.


-- 
With Best Regards,
Andy Shevchenko