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Message-ID: <ea8638fcd820e5b777bc6d5befc5eab9369edbbf.camel@sipsolutions.net>
Subject: Re: [PATCH] mac80211: prevent out of bounds access in
 ieee80211_rx_h_action()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Dan Carpenter <dan.carpenter@oracle.com>
Cc:     "John W. Linville" <linville@tuxdriver.com>,
        linux-wireless@vger.kernel.org, kernel-janitors@vger.kernel.org
Date:   Wed, 19 Jan 2022 14:56:52 +0100
In-Reply-To: <20220119125923.GB9509@kili>
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On Wed, 2022-01-19 at 15:59 +0300, Dan Carpenter wrote:
> Smatch complains that status->band comes from the skb->data
> 

Hmm. How does it come to that conclusion? It's not really true? It comes
from skb->cb, and the driver should fill it. Also, we have:

void ieee80211_rx_list(struct ieee80211_hw *hw, struct ieee80211_sta *pubsta,
                       struct sk_buff *skb, struct list_head *list)
{
...
        if (WARN_ON(status->band >= NUM_NL80211_BANDS))
                goto drop;


so I really don't think this patch is needed?

johannes