[PATCH] wifi: mt76: Fix memory leak after mt76_connac_mcu_alloc_sta_req()
From: Zilin Guan <hidden>
Date: 2026-01-16 14:49:26
Also in:
linux-mediatek, linux-wireless, lkml
Subsystem:
mediatek mt76 wireless lan driver, the rest · Maintainers:
Felix Fietkau, Lorenzo Bianconi, Ryder Lee, Linus Torvalds
mt76_connac_mcu_alloc_sta_req() allocates an skb which is expected to
be freed eventually by mt76_mcu_skb_send_msg(). However, currently if
an intermediate function fails before sending, the allocated skb is
leaked.
Specifically, mt76_connac_mcu_sta_wed_update() and
mt76_connac_mcu_sta_key_tlv() may fail, leading to an immediate memory
leak in the error path.
Fix this by explicitly freeing the skb in these error paths.
Commit 7c0f63fe37a5 ("wifi: mt76: mt7996: fix memory leak on
mt7996_mcu_sta_key_tlv error") made a similar change.
Compile tested only. Issue found using a prototype static analysis tool
and code review.
Fixes: d1369e515efe ("wifi: mt76: connac: introduce mt76_connac_mcu_sta_wed_update utility routine")
Fixes: 6683d988089c ("mt76: connac: move mt76_connac_mcu_add_key in connac module")
Fixes: 4f831d18d12d ("wifi: mt76: mt7915: enable WED RX support")
Fixes: c948b5da6bbe ("wifi: mt76: mt7925: add Mediatek Wi-Fi7 driver for mt7925 chips")
Signed-off-by: Zilin Guan <redacted>
---
.../net/wireless/mediatek/mt76/mt76_connac_mcu.c | 16 ++++++++++++----
drivers/net/wireless/mediatek/mt76/mt7915/mcu.c | 4 +++-
drivers/net/wireless/mediatek/mt76/mt7925/mcu.c | 4 +++-
3 files changed, 18 insertions(+), 6 deletions(-)
diff --git a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
index 0457712286d5..3f583e2a1dc1 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt76_connac_mcu.c@@ -1295,8 +1295,10 @@ int mt76_connac_mcu_sta_ba(struct mt76_dev *dev, struct mt76_vif_link *mvif, wtbl_hdr); ret = mt76_connac_mcu_sta_wed_update(dev, skb); - if (ret) + if (ret) { + dev_kfree_skb(skb); return ret; + } ret = mt76_mcu_skb_send_msg(dev, skb, cmd, true); if (ret)
@@ -1309,8 +1311,10 @@ int mt76_connac_mcu_sta_ba(struct mt76_dev *dev, struct mt76_vif_link *mvif, mt76_connac_mcu_sta_ba_tlv(skb, params, enable, tx); ret = mt76_connac_mcu_sta_wed_update(dev, skb); - if (ret) + if (ret) { + dev_kfree_skb(skb); return ret; + } return mt76_mcu_skb_send_msg(dev, skb, cmd, true); }
@@ -2764,12 +2768,16 @@ int mt76_connac_mcu_add_key(struct mt76_dev *dev, struct ieee80211_vif *vif, return PTR_ERR(skb); ret = mt76_connac_mcu_sta_key_tlv(sta_key_conf, skb, key, cmd); - if (ret) + if (ret) { + dev_kfree_skb(skb); return ret; + } ret = mt76_connac_mcu_sta_wed_update(dev, skb); - if (ret) + if (ret) { + dev_kfree_skb(skb); return ret; + } return mt76_mcu_skb_send_msg(dev, skb, mcu_cmd, true); }
diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
index 00bff4d3aab8..04ec821225eb 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c@@ -1765,8 +1765,10 @@ int mt7915_mcu_add_sta(struct mt7915_dev *dev, struct ieee80211_vif *vif, } out: ret = mt76_connac_mcu_sta_wed_update(&dev->mt76, skb); - if (ret) + if (ret) { + dev_kfree_skb(skb); return ret; + } return mt76_mcu_skb_send_msg(&dev->mt76, skb, MCU_EXT_CMD(STA_REC_UPDATE), true);
diff --git a/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c
index cf0fdea45cf7..3bddd357cd0d 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7925/mcu.c@@ -1288,8 +1288,10 @@ int mt7925_mcu_add_key(struct mt76_dev *dev, struct ieee80211_vif *vif, return PTR_ERR(skb); ret = mt7925_mcu_sta_key_tlv(wcid, sta_key_conf, skb, key, cmd, msta); - if (ret) + if (ret) { + dev_kfree_skb(skb); return ret; + } return mt76_mcu_skb_send_msg(dev, skb, mcu_cmd, true); }
--
2.34.1