mac80211: make sure data is accessible in EAPOL check (6dbda2d0) · Commits · 戴 / test

The code to allow EAPOL frames even when the station isn't yet marked associated needs to check that the incoming frame is long enough and due to paged RX it also can't assume skb->data contains the right data, it must use skb_copy_bits(). Fix this to avoid using data that doesn't really exist. Cc: stable@vger.kernel.org Signed-off-by:

Johannes Berg <johannes.berg@intel.com>

net/mac80211/rx.c

+10 −8

Original line number	Diff line number	Diff line
		@@ -888,14 +888,16 @@ ieee80211_rx_h_check(struct ieee80211_rx_data *rx)
		*/
		if (rx->sta && rx->sdata->vif.type == NL80211_IFTYPE_STATION &&
		ieee80211_is_data_present(hdr->frame_control)) {
		u16 ethertype;
		u8 *payload;

		payload = rx->skb->data +
		ieee80211_hdrlen(hdr->frame_control);
		ethertype = (payload[6] << 8) \| payload[7];
		if (cpu_to_be16(ethertype) ==
		rx->sdata->control_port_protocol)
		unsigned int hdrlen;
		__be16 ethertype;

		hdrlen = ieee80211_hdrlen(hdr->frame_control);

		if (rx->skb->len < hdrlen + 8)
		return RX_DROP_MONITOR;

		skb_copy_bits(rx->skb, hdrlen + 6, &ethertype, 2);
		if (ethertype == rx->sdata->control_port_protocol)
		return RX_CONTINUE;
		}

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