diff options
| author | Johannes Berg <johannes.berg@intel.com> | 2012-10-26 00:33:36 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-11-17 13:18:31 -0800 |
| commit | 1d45cb149a2ad467d5454a01ec60bff38b0ddfe4 (patch) | |
| tree | a71c4b9a38f021039612c9133175f2d933c96e17 | |
| parent | ec17483485122fbae70bb40d77aa1f0cf1916df2 (diff) | |
| download | lwn-1d45cb149a2ad467d5454a01ec60bff38b0ddfe4.tar.gz lwn-1d45cb149a2ad467d5454a01ec60bff38b0ddfe4.zip | |
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: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -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 1840ab56d0e7..3d8089b7fb5f 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -1430,7 +1430,6 @@ 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; @@ -2867,10 +2866,15 @@ static void __ieee80211_rx_handle_packet(struct ieee80211_hw *hw, if (ieee80211_is_data(fc) || ieee80211_is_mgmt(fc)) local->dot11ReceivedFragmentCount++; - 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); |