[PATCH] ieee80211: fix not allocating IV+ICV space when usingencryption in ieee80211_tx_frame

We should preallocate IV+ICV space when encrypting the frame.
Currently no problem shows up just because dev_alloc_skb aligns the
data len to SMP_CACHE_BYTES which can be used for ICV.

Signed-off-by: Hong Liu <hong.liu@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 11 insertions, 4 deletions

diff --git a/net/ieee80211/ieee80211_tx.c b/net/ieee80211/ieee80211_tx.c
index de148ae594f3..bf042139c7ab 100644
--- a/net/ieee80211/ieee80211_tx.c
+++ b/net/ieee80211/ieee80211_tx.c
@@ -562,10 +562,13 @@ int ieee80211_tx_frame(struct ieee80211_device *ieee,
         struct net_device_stats *stats = &ieee->stats;
         struct sk_buff *skb_frag;
         int priority = -1;
+        int fraglen = total_len;
+        int headroom = ieee->tx_headroom;
+        struct ieee80211_crypt_data *crypt = ieee->crypt[ieee->tx_keyidx];
 
         spin_lock_irqsave(&ieee->lock, flags);
 
-        if (encrypt_mpdu && !ieee->sec.encrypt)
+        if (encrypt_mpdu && (!ieee->sec.encrypt || !crypt))
                 encrypt_mpdu = 0;
 
         /* If there is no driver handler to take the TXB, dont' bother
@@ -581,20 +584,24 @@ int ieee80211_tx_frame(struct ieee80211_device *ieee,
                 goto success;
         }
 
-        if (encrypt_mpdu)
+        if (encrypt_mpdu) {
                 frame->frame_ctl |= cpu_to_le16(IEEE80211_FCTL_PROTECTED);
+                fraglen += crypt->ops->extra_mpdu_prefix_len +
+                           crypt->ops->extra_mpdu_postfix_len;
+                headroom += crypt->ops->extra_mpdu_prefix_len;
+        }
 
         /* When we allocate the TXB we allocate enough space for the reserve
          * and full fragment bytes (bytes_per_frag doesn't include prefix,
          * postfix, header, FCS, etc.) */
-        txb = ieee80211_alloc_txb(1, total_len, ieee->tx_headroom, GFP_ATOMIC);
+        txb = ieee80211_alloc_txb(1, fraglen, headroom, GFP_ATOMIC);
         if (unlikely(!txb)) {
                 printk(KERN_WARNING "%s: Could not allocate TXB\n",
                        ieee->dev->name);
                 goto failed;
         }
         txb->encrypted = 0;
-        txb->payload_size = total_len;
+        txb->payload_size = fraglen;
 
         skb_frag = txb->fragments[0];