3.2.93-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Rajkumar Manoharan <[email protected]> commit 5667c86acf021e6dcf02584408b4484a273ac68f upstream. 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: 9b395bc3be1c ("mac80211: verify that skb data is present") Signed-off-by: Rajkumar Manoharan <[email protected]> Signed-off-by: Johannes Berg <[email protected]> [bwh: Backported to 3.2: add mesh_flags variable in ieee80211_data_to_8023(), added separately upstream] Signed-off-by: Ben Hutchings <[email protected]> --- net/mac80211/rx.c | 3 ++- net/wireless/util.c | 10 ++++++---- 2 files changed, 8 insertions(+), 5 deletions(-) --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1959,7 +1959,8 @@ ieee80211_rx_h_mesh_fwding(struct ieee80 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; --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -360,12 +360,15 @@ int ieee80211_data_to_8023(struct sk_buf if (iftype == NL80211_IFTYPE_MESH_POINT) { struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); + u8 mesh_flags; + /* make sure meshdr->flags is on the linear part */ if (!pskb_may_pull(skb, hdrlen + 1)) return -1; - if (meshdr->flags & MESH_FLAGS_AE_A4) + mesh_flags = meshdr->flags & MESH_FLAGS_AE; + if (mesh_flags == MESH_FLAGS_AE_A4) return -1; - if (meshdr->flags & MESH_FLAGS_AE_A5_A6) { + if (mesh_flags == MESH_FLAGS_AE_A5_A6) { skb_copy_bits(skb, hdrlen + offsetof(struct ieee80211s_hdr, eaddr1), dst, ETH_ALEN); @@ -386,12 +389,15 @@ int ieee80211_data_to_8023(struct sk_buf if (iftype == NL80211_IFTYPE_MESH_POINT) { struct ieee80211s_hdr *meshdr = (struct ieee80211s_hdr *) (skb->data + hdrlen); + u8 mesh_flags; + /* make sure meshdr->flags is on the linear part */ if (!pskb_may_pull(skb, hdrlen + 1)) return -1; - if (meshdr->flags & MESH_FLAGS_AE_A5_A6) + mesh_flags = meshdr->flags & MESH_FLAGS_AE; + if (mesh_flags == MESH_FLAGS_AE_A5_A6) return -1; - if (meshdr->flags & MESH_FLAGS_AE_A4) + if (mesh_flags == MESH_FLAGS_AE_A4) skb_copy_bits(skb, hdrlen + offsetof(struct ieee80211s_hdr, eaddr1), src, ETH_ALEN);
