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Date:   Fri, 16 Sep 2022 14:31:22 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Peter Rosin <peda@axentia.se>, Wolfram Sang <wsa@kernel.org>,
        "Gustavo A. R. Silva" <gustavo@embeddedor.com>,
        linux-i2c@vger.kernel.org, linux-kernel@vger.kernel.org,
        kernel-janitors@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] i2c: mux: harden i2c_mux_alloc() against integer
 overflows
Message-ID: <202209160812.2B4AB7FC@keescook>
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On Fri, Sep 16, 2022 at 05:55:55PM +0300, Dan Carpenter wrote:
> On Fri, Sep 16, 2022 at 06:31:45AM -0700, Kees Cook wrote:
> > On Fri, Sep 16, 2022 at 11:23:25AM +0300, Dan Carpenter wrote:
> > > [...]
> > > net/ipv6/mcast.c:450 ip6_mc_source() saving 'size_add' to type 'int'
> > 
> > Interesting! Are you able to report the consumer? e.g. I think a bunch
> > of these would be fixed by:
> > 
> 
> Are you asking if I can add "passed to sock_kmalloc()" to the report?

Yeah.

> It's possible but it's kind of a headache the way this code is written.

Okay, no worries -- I was curious if it would be "easy". I can happily
just spit out the source line.

-- 
Kees Cook