diff options
author | Johannes Berg <johannes.berg@intel.com> | 2012-10-26 00:33:36 +0200 |
---|---|---|
committer | Ben Hutchings <ben@decadent.org.uk> | 2012-11-16 16:46:58 +0000 |
commit | c63cddefa8d6360353ba0e60f42b6c82f1c11b3c (patch) | |
tree | 7659b5f99bc89eabfe6b4102868d62823a904e61 /net | |
parent | 38f0512e7ed39ee586e125b82a358e962a34f9a8 (diff) |
mac80211: check management frame header length
commit 4a4f1a5808c8bb0b72a4f6e5904c53fb8c9cd966 upstream.
Due to pskb_may_pull() checking the skb length, all
non-management frames are checked on input whether
their 802.11 header is fully present. Also add that
check for management frames and remove a check that
is now duplicate. This prevents accessing skb data
beyond the frame end.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Diffstat (limited to 'net')
-rw-r--r-- | net/mac80211/rx.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 8c6f3378984..f9f8f36f42f 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1457,7 +1457,6 @@ ieee80211_rx_h_defragment(struct ieee80211_rx_data *rx) frag = sc & IEEE80211_SCTL_FRAG; if (likely((!ieee80211_has_morefrags(fc) && frag == 0) || - (rx->skb)->len < 24 || is_multicast_ether_addr(hdr->addr1))) { /* not fragmented */ goto out; @@ -2875,10 +2874,15 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, test_bit(SCAN_OFF_CHANNEL, &local->scanning))) status->rx_flags |= IEEE80211_RX_IN_SCAN; - if (ieee80211_is_mgmt(fc)) - err = skb_linearize(skb); - else + if (ieee80211_is_mgmt(fc)) { + /* drop frame if too short for header */ + if (skb->len < ieee80211_hdrlen(fc)) + err = -ENOBUFS; + else + err = skb_linearize(skb); + } else { err = !pskb_may_pull(skb, ieee80211_hdrlen(fc)); + } if (err) { dev_kfree_skb(skb); |