mac80211: clean up skb reallocation code
This cleans up the skb reallocation code to avoid problems with
skb->truesize, not resize an skb twice for a single output path
because we didn't expand it enough during the first copy and also
removes the code to further expand it during crypto operations
which will no longer be necessary.
Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
diff --git a/net/mac80211/wpa.c b/net/mac80211/wpa.c
index d6635f6..9f6fd20 100644
--- a/net/mac80211/wpa.c
+++ b/net/mac80211/wpa.c
@@ -79,6 +79,7 @@
struct sk_buff *skb = tx->skb;
int authenticator;
int wpa_test = 0;
+ int tail;
fc = tx->fc;
@@ -98,16 +99,13 @@
return TX_CONTINUE;
}
- if (skb_tailroom(skb) < MICHAEL_MIC_LEN) {
- I802_DEBUG_INC(tx->local->tx_expand_skb_head);
- if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN,
- MICHAEL_MIC_LEN + TKIP_ICV_LEN,
- GFP_ATOMIC))) {
- printk(KERN_DEBUG "%s: failed to allocate more memory "
- "for Michael MIC\n", tx->dev->name);
- return TX_DROP;
- }
- }
+ tail = MICHAEL_MIC_LEN;
+ if (!(tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE))
+ tail += TKIP_ICV_LEN;
+
+ if (WARN_ON(skb_tailroom(skb) < tail ||
+ skb_headroom(skb) < TKIP_IV_LEN))
+ return TX_DROP;
#if 0
authenticator = fc & IEEE80211_FCTL_FROMDS; /* FIX */
@@ -188,7 +186,7 @@
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
struct ieee80211_key *key = tx->key;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
- int hdrlen, len, tailneed;
+ int hdrlen, len, tail;
u16 fc;
u8 *pos;
@@ -199,7 +197,7 @@
!(tx->key->conf.flags & IEEE80211_KEY_FLAG_GENERATE_IV)) {
/* hwaccel - with no need for preallocated room for IV/ICV */
info->control.hw_key = &tx->key->conf;
- return TX_CONTINUE;
+ return 0;
}
fc = le16_to_cpu(hdr->frame_control);
@@ -207,17 +205,13 @@
len = skb->len - hdrlen;
if (tx->key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
- tailneed = 0;
+ tail = 0;
else
- tailneed = TKIP_ICV_LEN;
+ tail = TKIP_ICV_LEN;
- if ((skb_headroom(skb) < TKIP_IV_LEN ||
- skb_tailroom(skb) < tailneed)) {
- I802_DEBUG_INC(tx->local->tx_expand_skb_head);
- if (unlikely(pskb_expand_head(skb, TKIP_IV_LEN, tailneed,
- GFP_ATOMIC)))
- return -1;
- }
+ if (WARN_ON(skb_tailroom(skb) < tail ||
+ skb_headroom(skb) < TKIP_IV_LEN))
+ return -1;
pos = skb_push(skb, TKIP_IV_LEN);
memmove(pos, pos + TKIP_IV_LEN, hdrlen);
@@ -432,7 +426,7 @@
struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
struct ieee80211_key *key = tx->key;
struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
- int hdrlen, len, tailneed;
+ int hdrlen, len, tail;
u16 fc;
u8 *pos, *pn, *b_0, *aad, *scratch;
int i;
@@ -445,7 +439,7 @@
/* hwaccel - with no need for preallocated room for CCMP "
* header or MIC fields */
info->control.hw_key = &tx->key->conf;
- return TX_CONTINUE;
+ return 0;
}
scratch = key->u.ccmp.tx_crypto_buf;
@@ -457,17 +451,13 @@
len = skb->len - hdrlen;
if (key->flags & KEY_FLAG_UPLOADED_TO_HARDWARE)
- tailneed = 0;
+ tail = 0;
else
- tailneed = CCMP_MIC_LEN;
+ tail = CCMP_MIC_LEN;
- if ((skb_headroom(skb) < CCMP_HDR_LEN ||
- skb_tailroom(skb) < tailneed)) {
- I802_DEBUG_INC(tx->local->tx_expand_skb_head);
- if (unlikely(pskb_expand_head(skb, CCMP_HDR_LEN, tailneed,
- GFP_ATOMIC)))
- return -1;
- }
+ if (WARN_ON(skb_tailroom(skb) < tail ||
+ skb_headroom(skb) < CCMP_HDR_LEN))
+ return -1;
pos = skb_push(skb, CCMP_HDR_LEN);
memmove(pos, pos + CCMP_HDR_LEN, hdrlen);