From d5ad6ab61cbd89afdb60881f6274f74328af3ee9 Mon Sep 17 00:00:00 2001 From: Felix Fietkau Date: Sat, 14 Mar 2026 06:54:55 +0000 Subject: wifi: mac80211: always free skb on ieee80211_tx_prepare_skb() failure ieee80211_tx_prepare_skb() has three error paths, but only two of them free the skb. The first error path (ieee80211_tx_prepare() returning TX_DROP) does not free it, while invoke_tx_handlers() failure and the fragmentation check both do. Add kfree_skb() to the first error path so all three are consistent, and remove the now-redundant frees in callers (ath9k, mt76, mac80211_hwsim) to avoid double-free. Document the skb ownership guarantee in the function's kdoc. Signed-off-by: Felix Fietkau Link: https://patch.msgid.link/20260314065455.2462900-1-nbd@nbd.name Fixes: 06be6b149f7e ("mac80211: add ieee80211_tx_prepare_skb() helper function") Signed-off-by: Johannes Berg --- include/net/mac80211.h | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'include') diff --git a/include/net/mac80211.h b/include/net/mac80211.h index 7f9d96939a4e..adce2144a678 100644 --- a/include/net/mac80211.h +++ b/include/net/mac80211.h @@ -7407,7 +7407,9 @@ void ieee80211_report_wowlan_wakeup(struct ieee80211_vif *vif, * @band: the band to transmit on * @sta: optional pointer to get the station to send the frame to * - * Return: %true if the skb was prepared, %false otherwise + * Return: %true if the skb was prepared, %false otherwise. + * On failure, the skb is freed by this function; callers must not + * free it again. * * Note: must be called under RCU lock */ -- cgit v1.2.3