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Message-ID: <30984a540fb8e340c12e52054cdf7d6478b8b960.camel@perches.com>
Subject: Re: [PATCH] drivers/input: Remove all strcpy() uses in favor of
 strscpy()
From:   Joe Perches <joe@perches.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     "Russell King (Oracle)" <linux@armlinux.org.uk>,
        Len Baker <len.baker@gmx.com>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Lee Jones <lee.jones@linaro.org>,
        Uwe =?ISO-8859-1?Q?Kleine-K=F6nig?= 
        <u.kleine-koenig@pengutronix.de>, linux-hardening@vger.kernel.org,
        linux-input@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Mon, 02 Aug 2021 11:57:40 -0700
In-Reply-To: <202108020912.3807510B4B@keescook>
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On Mon, 2021-08-02 at 09:13 -0700, Kees Cook wrote:
> I'm wondering, instead, if we could convert strcpy() into this instead
> of adding another API? I.e. convert all the places that warn (if this
> were strcpy), and then land the conversion.

Perhaps not as strcpy is a builtin.

It might be easier as a cocci script.  Something like:

@@
char [] dest;
constant char [] src;
@@

*	strcpy(dest, src)

There are some additional test that needs to be added so that
only length(src) > length(dest) is reported.