From 9920eb4003c5e0f1447c2125c5c8e101b5ad8b8f Mon Sep 17 00:00:00 2001 From: Willem de Bruijn Date: Wed, 6 Mar 2019 14:35:15 -0500 Subject: [PATCH] bpf: only test gso type on gso packets [ Upstream commit 4c3024debf62de4c6ac6d3cb4c0063be21d4f652 ] BPF can adjust gso only for tcp bytestreams. Fail on other gso types. But only on gso packets. It does not touch this field if !gso_size. Fixes: b90efd225874 ("bpf: only adjust gso_size on bytestream protocols") Signed-off-by: Willem de Bruijn Acked-by: Yonghong Song Signed-off-by: Daniel Borkmann Signed-off-by: Sasha Levin --- include/linux/skbuff.h | 4 ++-- net/core/filter.c | 8 ++++---- 2 files changed, 6 insertions(+), 6 deletions(-) diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 3b0a25b..820903ce 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -4086,10 +4086,10 @@ static inline bool skb_is_gso_sctp(const struct sk_buff *skb) return skb_shinfo(skb)->gso_type & SKB_GSO_SCTP; } +/* Note: Should be called only if skb_is_gso(skb) is true */ static inline bool skb_is_gso_tcp(const struct sk_buff *skb) { - return skb_is_gso(skb) && - skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6); + return skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6); } static inline void skb_gso_reset(struct sk_buff *skb) diff --git a/net/core/filter.c b/net/core/filter.c index b1369ed..eb81e9d 100644 --- a/net/core/filter.c +++ b/net/core/filter.c @@ -2614,7 +2614,7 @@ static int bpf_skb_proto_4_to_6(struct sk_buff *skb) u32 off = skb_mac_header_len(skb); int ret; - if (!skb_is_gso_tcp(skb)) + if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_cow(skb, len_diff); @@ -2655,7 +2655,7 @@ static int bpf_skb_proto_6_to_4(struct sk_buff *skb) u32 off = skb_mac_header_len(skb); int ret; - if (!skb_is_gso_tcp(skb)) + if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_unclone(skb, GFP_ATOMIC); @@ -2780,7 +2780,7 @@ static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff) u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); int ret; - if (!skb_is_gso_tcp(skb)) + if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_cow(skb, len_diff); @@ -2809,7 +2809,7 @@ static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff) u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb); int ret; - if (!skb_is_gso_tcp(skb)) + if (skb_is_gso(skb) && !skb_is_gso_tcp(skb)) return -ENOTSUPP; ret = skb_unclone(skb, GFP_ATOMIC); -- 2.7.4