queue-4.19/bpf-only-test-gso-type-on-gso-packets.patch

   1 From f1fbe7fd6984e96f2a84bab9d47de7225db66581 Mon Sep 17 00:00:00 2001
   2 From: Willem de Bruijn <willemb@google.com>
   3 Date: Wed, 6 Mar 2019 14:35:15 -0500
   4 Subject: bpf: only test gso type on gso packets
   5
   6 [ Upstream commit 4c3024debf62de4c6ac6d3cb4c0063be21d4f652 ]
   7
   8 BPF can adjust gso only for tcp bytestreams. Fail on other gso types.
   9
  10 But only on gso packets. It does not touch this field if !gso_size.
  11
  12 Fixes: b90efd225874 ("bpf: only adjust gso_size on bytestream protocols")
  13 Signed-off-by: Willem de Bruijn <willemb@google.com>
  14 Acked-by: Yonghong Song <yhs@fb.com>
  15 Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
  16 Signed-off-by: Sasha Levin <sashal@kernel.org>
  17 ---
  18  include/linux/skbuff.h | 4 ++--
  19  net/core/filter.c      | 8 ++++----
  20  2 files changed, 6 insertions(+), 6 deletions(-)
  21
  22 diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h
  23 index 3b0a25bb7c6f..820903ceac4f 100644
  24 --- a/include/linux/skbuff.h
  25 +++ b/include/linux/skbuff.h
  26 @@ -4086,10 +4086,10 @@ static inline bool skb_is_gso_sctp(const struct sk_buff *skb)
  27         return skb_shinfo(skb)->gso_type & SKB_GSO_SCTP;
  28  }
  29
  30 +/* Note: Should be called only if skb_is_gso(skb) is true */
  31  static inline bool skb_is_gso_tcp(const struct sk_buff *skb)
  32  {
  33 -       return skb_is_gso(skb) &&
  34 -              skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6);
  35 +       return skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6);
  36  }
  37
  38  static inline void skb_gso_reset(struct sk_buff *skb)
  39 diff --git a/net/core/filter.c b/net/core/filter.c
  40 index b1369edce113..eb81e9db4093 100644
  41 --- a/net/core/filter.c
  42 +++ b/net/core/filter.c
  43 @@ -2614,7 +2614,7 @@ static int bpf_skb_proto_4_to_6(struct sk_buff *skb)
  44         u32 off = skb_mac_header_len(skb);
  45         int ret;
  46
  47 -       if (!skb_is_gso_tcp(skb))
  48 +       if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
  49                 return -ENOTSUPP;
  50
  51         ret = skb_cow(skb, len_diff);
  52 @@ -2655,7 +2655,7 @@ static int bpf_skb_proto_6_to_4(struct sk_buff *skb)
  53         u32 off = skb_mac_header_len(skb);
  54         int ret;
  55
  56 -       if (!skb_is_gso_tcp(skb))
  57 +       if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
  58                 return -ENOTSUPP;
  59
  60         ret = skb_unclone(skb, GFP_ATOMIC);
  61 @@ -2780,7 +2780,7 @@ static int bpf_skb_net_grow(struct sk_buff *skb, u32 len_diff)
  62         u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
  63         int ret;
  64
  65 -       if (!skb_is_gso_tcp(skb))
  66 +       if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
  67                 return -ENOTSUPP;
  68
  69         ret = skb_cow(skb, len_diff);
  70 @@ -2809,7 +2809,7 @@ static int bpf_skb_net_shrink(struct sk_buff *skb, u32 len_diff)
  71         u32 off = skb_mac_header_len(skb) + bpf_skb_net_base_len(skb);
  72         int ret;
  73
  74 -       if (!skb_is_gso_tcp(skb))
  75 +       if (skb_is_gso(skb) && !skb_is_gso_tcp(skb))
  76                 return -ENOTSUPP;
  77
  78         ret = skb_unclone(skb, GFP_ATOMIC);
  79 --
  80 2.19.1
  81