From da8507851e66a227a6cbf8b487bd8a23f53cc98b Mon Sep 17 00:00:00 2001 From: Eason Lai Date: Fri, 3 Jul 2026 08:59:45 +0800 Subject: [PATCH] wifi: mt76: mt792x: Fix memory leak in SDIO TX path When tx_prepare_skb() returns an error in the SDIO TX path, the skb is not freed, leading to a memory leak. This can occur when zero-length frames (such as WNM NULL frames) are dropped to prevent potential hardware TX hangs. Fix this by properly releasing the skb with ieee80211_tx_status_ext() when tx_prepare_skb() fails. Fixes: b747fa343817 ("mt76: mt7915: drop zero-length packet to avoid Tx hang") Signed-off-by: Eason Lai Link: https://patch.msgid.link/20260703005945.2244533-1-eason.lai@mediatek.com Signed-off-by: Felix Fietkau --- sdio.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/sdio.c b/sdio.c index 8bae77c7..ba5f123f 100644 --- a/sdio.c +++ b/sdio.c @@ -519,6 +519,10 @@ mt76s_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q, enum mt76_txq_id qid, struct sk_buff *skb, struct mt76_wcid *wcid, struct ieee80211_sta *sta) { + struct ieee80211_tx_status status = { + .sta = sta, + }; + struct mt76_tx_info tx_info = { .skb = skb, }; @@ -531,8 +535,13 @@ mt76s_tx_queue_skb(struct mt76_phy *phy, struct mt76_queue *q, skb->prev = skb->next = NULL; err = dev->drv->tx_prepare_skb(dev, NULL, qid, wcid, sta, &tx_info); - if (err < 0) + if (err < 0) { + status.skb = tx_info.skb; + spin_lock_bh(&dev->rx_lock); + ieee80211_tx_status_ext(dev->hw, &status); + spin_unlock_bh(&dev->rx_lock); return err; + } q->entry[q->head].skb = tx_info.skb; q->entry[q->head].buf_sz = len;