From abf981bb8de6185b2ac80ebc40224d5028e4f8b4 Mon Sep 17 00:00:00 2001 From: Oliver Hartkopp Date: Thu, 5 Feb 2026 15:44:05 +0100 Subject: [PATCH] net: skb: allow up to 8 skb extension ids The skb extension ids range from 0 .. 7 to fit their bits as flags into a single byte. The ids are automatically enumnerated in enum skb_ext_id in skbuff.h, where SKB_EXT_NUM is defined as the last value. When having 8 skb extension ids (0 .. 7), SKB_EXT_NUM becomes 8 which is a valid value for SKB_EXT_NUM. Fixes: 96ea3a1e2d31 ("can: add CAN skb extension infrastructure") Link: https://lore.kernel.org/netdev/aXoMqaA7b2CqJZNA@strlen.de/ Reviewed-by: Florian Westphal Signed-off-by: Oliver Hartkopp Link: https://patch.msgid.link/20260205-skb_ext-v1-1-9ba992ccee8b@hartkopp.net Signed-off-by: Jakub Kicinski --- net/core/skbuff.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/core/skbuff.c b/net/core/skbuff.c index 45809986dfe17..699c401a5eae9 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -5158,7 +5158,7 @@ static __always_inline unsigned int skb_ext_total_length(void) static void skb_extensions_init(void) { - BUILD_BUG_ON(SKB_EXT_NUM >= 8); + BUILD_BUG_ON(SKB_EXT_NUM > 8); #if !IS_ENABLED(CONFIG_KCOV_INSTRUMENT_ALL) BUILD_BUG_ON(skb_ext_total_length() > 255); #endif -- 2.47.3