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Date:   Tue, 12 Dec 2023 13:26:14 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Justin Stitt <justinstitt@google.com>
Cc:     Jonathan Cameron <jic23@kernel.org>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Stephen Boyd <swboyd@chromium.org>, linux-iio@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH v3] iio: sx9324: avoid copying property strings
Message-ID: <202312121325.E29472E0C0@keescook>
References: <20231212-strncpy-drivers-iio-proximity-sx9324-c-v3-1-b8ae12fc8a5d@google.com>
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On Tue, Dec 12, 2023 at 12:42:52AM +0000, Justin Stitt wrote:
> We're doing some needless string copies when trying to assign the proper
> `prop` string. We can make `prop` a const char* and simply assign to
> string literals.
> 
> For the case where a format string is used, let's extract the parsing
> logic out into sx9324_parse_phase_prop(). We no longer need to create
> copies or allocate new memory.
> 
> sx9324_parse_phase_prop() will simply return the default def value if it
> fails.
> 
> This also cleans up some deprecated strncpy() uses [1].
> 
> Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
> Link: https://github.com/KSPP/linux/issues/90
> Cc: linux-hardening@vger.kernel.org
> Signed-off-by: Justin Stitt <justinstitt@google.com>

Yeah, I like this approach. Totally removes the string copying and
creates a helper that does the "heavy lifting". :)

Reviewed-by: Kees Cook <keescook@chromium.org>

-- 
Kees Cook