[PATCH 4.19 087/293] mac80211: Fix insufficient headroom issue for AMSDU

[Greg Kroah-Hartman]

From: Chih-Kang Chang <gary.chang@xxxxxxxxxxx>

[ Upstream commit f50d2ff8f016b79a2ff4acd5943a1eda40c545d4 ]

ieee80211_amsdu_realloc_pad() fails to account for extra_tx_headroom,
the original reserved headroom might be eaten. Add the necessary
extra_tx_headroom.

Fixes: 6e0456b54545 ("mac80211: add A-MSDU tx support")
Signed-off-by: Chih-Kang Chang <gary.chang@xxxxxxxxxxx>
Signed-off-by: Ping-Ke Shih <pkshih@xxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210816085128.10931-2-pkshih@xxxxxxxxxxx
[fix indentation]
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 net/mac80211/tx.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 3530d1a5fc98..5c5908127fcb 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -3142,7 +3142,9 @@ static bool ieee80211_amsdu_prepare_head(struct ieee80211_sub_if_data *sdata,
 	if (info->control.flags & IEEE80211_TX_CTRL_AMSDU)
 		return true;
 
-	if (!ieee80211_amsdu_realloc_pad(local, skb, sizeof(*amsdu_hdr)))
+	if (!ieee80211_amsdu_realloc_pad(local, skb,
+					 sizeof(*amsdu_hdr) +
+					 local->hw.extra_tx_headroom))
 		return false;
 
 	data = skb_push(skb, sizeof(*amsdu_hdr));
-- 
2.30.2