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References: <20230620200832.3379741-1-azeemshaikh38@gmail.com> <202306201311.862B05981F@keescook>
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From:   Azeem Shaikh <azeemshaikh38@gmail.com>
Date:   Sun, 9 Jul 2023 22:36:44 -0400
Message-ID: <CADmuW3XKZkYB4dKPa2Bsoj96CK4hT_8cwV++7rEFP=Wxw7hGvQ@mail.gmail.com>
Subject: Re: [PATCH v2] crypto: Replace strlcpy with strscpy
To:     Kees Cook <keescook@chromium.org>
Cc:     Herbert Xu <herbert@gondor.apana.org.au>,
        "David S. Miller" <davem@davemloft.net>,
        Eric Biggers <ebiggers@kernel.org>,
        linux-hardening@vger.kernel.org, linux-crypto@vger.kernel.org,
        linux-kernel@vger.kernel.org
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On Tue, Jun 20, 2023 at 4:12=E2=80=AFPM Kees Cook <keescook@chromium.org> w=
rote:
>
> On Tue, Jun 20, 2023 at 08:08:32PM +0000, Azeem Shaikh wrote:
> > strlcpy() reads the entire source buffer first.
> > This read may exceed the destination size limit.
> > This is both inefficient and can lead to linear read
> > overflows if a source string is not NUL-terminated [1].
> > In an effort to remove strlcpy() completely [2], replace
> > strlcpy() here with strscpy().
> >
> > Direct replacement is safe here since return value of -errno
> > is used to check for truncation instead of sizeof(dest).
> >
> > [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strl=
cpy
> > [2] https://github.com/KSPP/linux/issues/89
> >
> > Signed-off-by: Azeem Shaikh <azeemshaikh38@gmail.com>
>
> Thanks for fixing up the variable type. (And thank you Eric for catching
> the signedness problem!)
>
> Reviewed-by: Kees Cook <keescook@chromium.org>
>

Friendly ping on this.