Date:   Tue, 7 Dec 2021 14:21:05 +0200
From:   Mika Westerberg <mika.westerberg@linux.intel.com>
To:     Kees Cook <keescook@chromium.org>
Cc:     Andreas Noever <andreas.noever@gmail.com>,
        Michael Jamet <michael.jamet@intel.com>,
        Yehezkel Bernat <YehezkelShB@gmail.com>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>, linux-kernel@vger.kernel.org,
        linux-usb@vger.kernel.org, netdev@vger.kernel.org,
        linux-hardening@vger.kernel.org
Subject: Re: [PATCH] thunderbolt: xdomain: Avoid potential stack OOB read
Message-ID: <Ya9Rsfos46i8Rcpc@lahna>
References: <20211207063413.2698788-1-keescook@chromium.org>
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On Mon, Dec 06, 2021 at 10:34:13PM -0800, Kees Cook wrote:
> tb_xdp_properties_changed_request() was calling tb_xdp_handle_error() with
> a struct tb_xdp_properties_changed_response on the stack, which does not
> have the "error" field present when cast to struct tb_xdp_error_response.
> This was detected when building with -Warray-bounds:
> 
> drivers/thunderbolt/xdomain.c: In function 'tb_xdomain_properties_changed':
> drivers/thunderbolt/xdomain.c:226:22: error: array subscript 'const struct tb_xdp_error_response[0]' is partly outside array bounds of 'struct tb_xdp_properties_changed_response[1]' [-Werror=array-bounds]
>   226 |         switch (error->error) {
>       |                 ~~~~~^~~~~~~
> drivers/thunderbolt/xdomain.c:448:51: note: while referencing 'res'
>   448 |         struct tb_xdp_properties_changed_response res;
>       |                                                   ^~~
> 
> Add union containing struct tb_xdp_error_response to structures passed
> to tb_xdp_handle_error(), so that the "error" field will be present.
> 
> Signed-off-by: Kees Cook <keescook@chromium.org>

Applied, thanks!