From d35d1375493b0f962a5da5aef015b8bd215e059d Mon Sep 17 00:00:00 2001 From: Sven Eckelmann Date: Tue, 24 Nov 2020 17:59:16 +0200 Subject: [PATCH] ath11k: Build check size of ath11k_skb_cb It is rather easy to add more entries to ath11k_skb_cb while forgetting the size limit of ieee80211_tx_info->driver_data. So just check this during the build to reduce the change of accidental buffer overflow in the skbuff->cb. Signed-off-by: Sven Eckelmann Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20201119154235.263250-3-sven@narfation.org --- drivers/net/wireless/ath/ath11k/core.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/net/wireless/ath/ath11k/core.h b/drivers/net/wireless/ath/ath11k/core.h index 25609ff..317b15e 100644 --- a/drivers/net/wireless/ath/ath11k/core.h +++ b/drivers/net/wireless/ath/ath11k/core.h @@ -909,6 +909,8 @@ static inline const char *ath11k_scan_state_str(enum ath11k_scan_state state) static inline struct ath11k_skb_cb *ATH11K_SKB_CB(struct sk_buff *skb) { + BUILD_BUG_ON(sizeof(struct ath11k_skb_cb) > + IEEE80211_TX_INFO_DRIVER_DATA_SIZE); return (struct ath11k_skb_cb *)&IEEE80211_SKB_CB(skb)->driver_data; } -- 2.7.4