Commit 5667c86a authored by Rajkumar Manoharan's avatar Rajkumar Manoharan Committed by Johannes Berg
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mac80211: strictly check mesh address extension mode 



Mesh forwarding path checks for address extension mode to fetch
appropriate proxied address and MPP address. Existing condition
that looks for 6 address format is not strict enough so that
frames with improper values are processed and invalid entries
are added into MPP table. Fix that by adding a stricter check before
processing the packet.

Per IEEE Std 802.11s-2011 spec. Table 7-6g1 lists address extension
mode 0x3 as reserved one. And also Table Table 9-13 does not specify
0x3 as valid address field.

Fixes: 9b395bc3 ("mac80211: verify that skb data is present")
Signed-off-by: default avatarRajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 29cee56c

net/mac80211/rx.c

+2 −1
Original line number Diff line number Diff line
@@ -2492,7 +2492,8 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx) 
		if (is_multicast_ether_addr(hdr->addr1)) {

			mpp_addr = hdr->addr3;

			proxied_addr = mesh_hdr->eaddr1;

		} else if (mesh_hdr->flags & MESH_FLAGS_AE_A5_A6) {

		} else if ((mesh_hdr->flags & MESH_FLAGS_AE) ==

			    MESH_FLAGS_AE_A5_A6) {

			/* has_a4 already checked in ieee80211_rx_mesh_check */

			mpp_addr = hdr->addr4;

			proxied_addr = mesh_hdr->eaddr2;

net/wireless/util.c

+6 −4
Original line number Diff line number Diff line
@@ -454,6 +454,8 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, 
	if (iftype == NL80211_IFTYPE_MESH_POINT)

		skb_copy_bits(skb, hdrlen, &mesh_flags, 1);



	mesh_flags &= MESH_FLAGS_AE;



	switch (hdr->frame_control &

		cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {

	case cpu_to_le16(IEEE80211_FCTL_TODS):
@@ -469,9 +471,9 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, 
			     iftype != NL80211_IFTYPE_STATION))

			return -1;

		if (iftype == NL80211_IFTYPE_MESH_POINT) {

			if (mesh_flags & MESH_FLAGS_AE_A4)

			if (mesh_flags == MESH_FLAGS_AE_A4)

				return -1;

			if (mesh_flags & MESH_FLAGS_AE_A5_A6) {

			if (mesh_flags == MESH_FLAGS_AE_A5_A6) {

				skb_copy_bits(skb, hdrlen +

					offsetof(struct ieee80211s_hdr, eaddr1),

					tmp.h_dest, 2 * ETH_ALEN);
@@ -487,9 +489,9 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, 
		     ether_addr_equal(tmp.h_source, addr)))

			return -1;

		if (iftype == NL80211_IFTYPE_MESH_POINT) {

			if (mesh_flags & MESH_FLAGS_AE_A5_A6)

			if (mesh_flags == MESH_FLAGS_AE_A5_A6)

				return -1;

			if (mesh_flags & MESH_FLAGS_AE_A4)

			if (mesh_flags == MESH_FLAGS_AE_A4)

				skb_copy_bits(skb, hdrlen +

					offsetof(struct ieee80211s_hdr, eaddr1),

					tmp.h_source, ETH_ALEN);

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