From: Alexander Duyck Date: Thu, 26 Jan 2023 11:06:59 -0800 Subject: [PATCH] skb: Do mix page pool and page referenced frags in GRO GSO should not merge page pool recycled frames with standard reference counted frames. Traditionally this didn't occur, at least not often. However as we start looking at adding support for wireless adapters there becomes the potential to mix the two due to A-MSDU repartitioning frames in the receive path. There are possibly other places where this may have occurred however I suspect they must be few and far between as we have not seen this issue until now. Fixes: 53e0961da1c7 ("page_pool: add frag page recycling support in page pool") Reported-by: Felix Fietkau Signed-off-by: Alexander Duyck --- --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -4359,6 +4359,15 @@ int skb_gro_receive(struct sk_buff *p, s if (unlikely(p->len + len >= 65536 || NAPI_GRO_CB(skb)->flush)) return -E2BIG; + /* Do not splice page pool based packets w/ non-page pool + * packets. This can result in reference count issues as page + * pool pages will not decrement the reference count and will + * instead be immediately returned to the pool or have frag + * count decremented. + */ + if (p->pp_recycle != skb->pp_recycle) + return -ETOOMANYREFS; + lp = NAPI_GRO_CB(p)->last; pinfo = skb_shinfo(lp);