Message-ID: <a54298c0b747ba562caa47f271f058b9831810ee.camel@sipsolutions.net>
Subject: Re: [PATCH mac80211] cfg80211: check nla_parse_nested return code
 in nl80211_set_sar_specs
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Lorenzo Bianconi <lorenzo@kernel.org>
Cc:     linux-wireless@vger.kernel.org, lorenzo.bianconi@redhat.com,
        cjhuang@codeaurora.org
Date:   Mon, 22 Nov 2021 09:18:10 +0100
In-Reply-To: <3b6fee130e2d264242463cff063bcfb6d6f5da83.1637494779.git.lorenzo@kernel.org>
References: <3b6fee130e2d264242463cff063bcfb6d6f5da83.1637494779.git.lorenzo@kernel.org>
Content-Type: text/plain; charset="UTF-8"
User-Agent: Evolution 3.42.1 (3.42.1-1.fc35) 
MIME-Version: 1.0
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Sun, 2021-11-21 at 12:41 +0100, Lorenzo Bianconi wrote:
> Check error code returned by nla_parse_nested in nl80211_set_sar_specs
> routine before parsing SAR sub-specs.
> 

I don't think we need to. The policy already states it:

        [NL80211_ATTR_SAR_SPEC] = NLA_POLICY_NESTED(sar_policy),


Since we always parse the top-level already in the generic netlink code,
it will recurse down here by way of that policy link, and then it will
already be validated as much as nla_parse_nested() can do again - so we
only do it again here to actually get access to the pointers.

johannes