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: 9b395bc3be ("mac80211: verify that skb data is present")
Signed-off-by: Rajkumar Manoharan <rmanohar@qti.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
This commit is contained in:
Rajkumar Manoharan 2017-05-14 21:41:55 -07:00 committed by Johannes Berg
parent 29cee56c0b
commit 5667c86acf
2 changed files with 8 additions and 5 deletions

View File

@ -2492,7 +2492,8 @@ ieee80211_rx_h_mesh_fwding(struct ieee80211_rx_data *rx)
if (is_multicast_ether_addr(hdr->addr1)) { if (is_multicast_ether_addr(hdr->addr1)) {
mpp_addr = hdr->addr3; mpp_addr = hdr->addr3;
proxied_addr = mesh_hdr->eaddr1; 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 */ /* has_a4 already checked in ieee80211_rx_mesh_check */
mpp_addr = hdr->addr4; mpp_addr = hdr->addr4;
proxied_addr = mesh_hdr->eaddr2; proxied_addr = mesh_hdr->eaddr2;

View File

@ -454,6 +454,8 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr,
if (iftype == NL80211_IFTYPE_MESH_POINT) if (iftype == NL80211_IFTYPE_MESH_POINT)
skb_copy_bits(skb, hdrlen, &mesh_flags, 1); skb_copy_bits(skb, hdrlen, &mesh_flags, 1);
mesh_flags &= MESH_FLAGS_AE;
switch (hdr->frame_control & switch (hdr->frame_control &
cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) { cpu_to_le16(IEEE80211_FCTL_TODS | IEEE80211_FCTL_FROMDS)) {
case cpu_to_le16(IEEE80211_FCTL_TODS): 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)) iftype != NL80211_IFTYPE_STATION))
return -1; return -1;
if (iftype == NL80211_IFTYPE_MESH_POINT) { if (iftype == NL80211_IFTYPE_MESH_POINT) {
if (mesh_flags & MESH_FLAGS_AE_A4) if (mesh_flags == MESH_FLAGS_AE_A4)
return -1; return -1;
if (mesh_flags & MESH_FLAGS_AE_A5_A6) { if (mesh_flags == MESH_FLAGS_AE_A5_A6) {
skb_copy_bits(skb, hdrlen + skb_copy_bits(skb, hdrlen +
offsetof(struct ieee80211s_hdr, eaddr1), offsetof(struct ieee80211s_hdr, eaddr1),
tmp.h_dest, 2 * ETH_ALEN); 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))) ether_addr_equal(tmp.h_source, addr)))
return -1; return -1;
if (iftype == NL80211_IFTYPE_MESH_POINT) { if (iftype == NL80211_IFTYPE_MESH_POINT) {
if (mesh_flags & MESH_FLAGS_AE_A5_A6) if (mesh_flags == MESH_FLAGS_AE_A5_A6)
return -1; return -1;
if (mesh_flags & MESH_FLAGS_AE_A4) if (mesh_flags == MESH_FLAGS_AE_A4)
skb_copy_bits(skb, hdrlen + skb_copy_bits(skb, hdrlen +
offsetof(struct ieee80211s_hdr, eaddr1), offsetof(struct ieee80211s_hdr, eaddr1),
tmp.h_source, ETH_ALEN); tmp.h_source, ETH_ALEN);