Commit fc7c976d authored Feb 07, 2011 by Felix Fietkau Committed by John W. Linville Feb 07, 2011

mac80211: fix the skb cloned check in the tx path



Using skb_header_cloned to check if it's safe to write to the skb is not
enough - mac80211 also touches the tailroom of the skb.
Initially this check was only used to increase a counter, however this
commit changed the code to also skip skb data reallocation if no extra
head/tailroom was needed:

commit 4cd06a34
mac80211: skip unnecessary pskb_expand_head calls

It added a regression at least with iwl3945, which is fixed by this patch.

Reported-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Tested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

parent 3dd823e6

net/mac80211/tx.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -1547,7 +1547,7 @@ static int ieee80211_skb_resize(struct ieee80211_local *local,
		skb_orphan(skb);
		}

		if (skb_header_cloned(skb))
		if (skb_cloned(skb))
		I802_DEBUG_INC(local->tx_expand_skb_head_cloned);
		else if (head_need \|\| tail_need)
		I802_DEBUG_INC(local->tx_expand_skb_head);

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