diff options
| author | Felix Fietkau <nbd@nbd.name> | 2022-10-07 14:56:11 +0200 |
|---|---|---|
| committer | Johannes Berg <johannes.berg@intel.com> | 2022-10-07 14:57:20 +0200 |
| commit | d9e249704084982ac7581a560ffa284e11621d43 (patch) | |
| tree | f7927b33e00185fa9310a0a48348e8e60ca9a983 /net/wireless | |
| parent | c95014e1d05b5acfd9e6fbe5d1f048b07c6902ff (diff) | |
wifi: cfg80211: fix ieee80211_data_to_8023_exthdr handling of small packets
STP topology change notification packets only have a payload of 7 bytes,
so they get dropped due to the skb->len < hdrlen + 8 check.
Fix this by removing the extra 8 from the skb->len check and checking the
return code on the skb_copy_bits calls.
Fixes: 2d1c304cb2d5 ("cfg80211: add function for 802.3 conversion with separate output buffer")
Reported-by: Chad Monroe <chad.monroe@smartrg.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Diffstat (limited to 'net/wireless')
| -rw-r--r-- | net/wireless/util.c | 40 |
1 files changed, 21 insertions, 19 deletions
diff --git a/net/wireless/util.c b/net/wireless/util.c index 01493568a21d..1f285b515028 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -559,7 +559,7 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, return -1; hdrlen = ieee80211_hdrlen(hdr->frame_control) + data_offset; - if (skb->len < hdrlen + 8) + if (skb->len < hdrlen) return -1; /* convert IEEE 802.11 header + possible LLC headers into Ethernet @@ -574,8 +574,9 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, memcpy(tmp.h_dest, ieee80211_get_DA(hdr), ETH_ALEN); memcpy(tmp.h_source, ieee80211_get_SA(hdr), ETH_ALEN); - if (iftype == NL80211_IFTYPE_MESH_POINT) - skb_copy_bits(skb, hdrlen, &mesh_flags, 1); + if (iftype == NL80211_IFTYPE_MESH_POINT && + skb_copy_bits(skb, hdrlen, &mesh_flags, 1) < 0) + return -1; mesh_flags &= MESH_FLAGS_AE; @@ -595,11 +596,12 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, if (iftype == NL80211_IFTYPE_MESH_POINT) { if (mesh_flags == MESH_FLAGS_AE_A4) return -1; - if (mesh_flags == MESH_FLAGS_AE_A5_A6) { - skb_copy_bits(skb, hdrlen + - offsetof(struct ieee80211s_hdr, eaddr1), - tmp.h_dest, 2 * ETH_ALEN); - } + if (mesh_flags == MESH_FLAGS_AE_A5_A6 && + skb_copy_bits(skb, hdrlen + + offsetof(struct ieee80211s_hdr, eaddr1), + tmp.h_dest, 2 * ETH_ALEN) < 0) + return -1; + hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags); } break; @@ -613,10 +615,11 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, if (iftype == NL80211_IFTYPE_MESH_POINT) { if (mesh_flags == MESH_FLAGS_AE_A5_A6) return -1; - if (mesh_flags == MESH_FLAGS_AE_A4) - skb_copy_bits(skb, hdrlen + - offsetof(struct ieee80211s_hdr, eaddr1), - tmp.h_source, ETH_ALEN); + if (mesh_flags == MESH_FLAGS_AE_A4 && + skb_copy_bits(skb, hdrlen + + offsetof(struct ieee80211s_hdr, eaddr1), + tmp.h_source, ETH_ALEN) < 0) + return -1; hdrlen += __ieee80211_get_mesh_hdrlen(mesh_flags); } break; @@ -628,16 +631,15 @@ int ieee80211_data_to_8023_exthdr(struct sk_buff *skb, struct ethhdr *ehdr, break; } - skb_copy_bits(skb, hdrlen, &payload, sizeof(payload)); - tmp.h_proto = payload.proto; - - if (likely((!is_amsdu && ether_addr_equal(payload.hdr, rfc1042_header) && - tmp.h_proto != htons(ETH_P_AARP) && - tmp.h_proto != htons(ETH_P_IPX)) || - ether_addr_equal(payload.hdr, bridge_tunnel_header))) { + if (likely(skb_copy_bits(skb, hdrlen, &payload, sizeof(payload)) == 0 && + ((!is_amsdu && ether_addr_equal(payload.hdr, rfc1042_header) && + payload.proto != htons(ETH_P_AARP) && + payload.proto != htons(ETH_P_IPX)) || + ether_addr_equal(payload.hdr, bridge_tunnel_header)))) { /* remove RFC1042 or Bridge-Tunnel encapsulation and * replace EtherType */ hdrlen += ETH_ALEN + 2; + tmp.h_proto = payload.proto; skb_postpull_rcsum(skb, &payload, ETH_ALEN + 2); } else { tmp.h_proto = htons(skb->len - hdrlen); |