From 850a88cc4096fe1df407452ba2e4d28cf5b3eee9 Mon Sep 17 00:00:00 2001 From: Stanislav Fomichev Date: Fri, 13 Dec 2019 14:30:27 -0800 Subject: [PATCH] bpf: Expose __sk_buff wire_len/gso_segs to BPF_PROG_TEST_RUN wire_len should not be less than real len and is capped by GSO_MAX_SIZE. gso_segs is capped by GSO_MAX_SEGS. v2: * set wire_len to skb->len when passed wire_len is 0 (Alexei Starovoitov) Signed-off-by: Stanislav Fomichev Signed-off-by: Alexei Starovoitov Cc: Martin KaFai Lau Link: https://lore.kernel.org/bpf/20191213223028.161282-1-sdf@google.com --- net/bpf/test_run.c | 19 ++++++++++++++++++- 1 file changed, 18 insertions(+), 1 deletion(-) diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c index 5016c538d3ce..93a9c87787e0 100644 --- a/net/bpf/test_run.c +++ b/net/bpf/test_run.c @@ -267,8 +267,10 @@ static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb) return -EINVAL; /* tstamp is allowed */ + /* wire_len is allowed */ + /* gso_segs is allowed */ - if (!range_is_zero(__skb, offsetofend(struct __sk_buff, tstamp), + if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_segs), sizeof(struct __sk_buff))) return -EINVAL; @@ -276,6 +278,19 @@ static int convert___skb_to_skb(struct sk_buff *skb, struct __sk_buff *__skb) skb->tstamp = __skb->tstamp; memcpy(&cb->data, __skb->cb, QDISC_CB_PRIV_LEN); + if (__skb->wire_len == 0) { + cb->pkt_len = skb->len; + } else { + if (__skb->wire_len < skb->len || + __skb->wire_len > GSO_MAX_SIZE) + return -EINVAL; + cb->pkt_len = __skb->wire_len; + } + + if (__skb->gso_segs > GSO_MAX_SEGS) + return -EINVAL; + skb_shinfo(skb)->gso_segs = __skb->gso_segs; + return 0; } @@ -289,6 +304,8 @@ static void convert_skb_to___skb(struct sk_buff *skb, struct __sk_buff *__skb) __skb->priority = skb->priority; __skb->tstamp = skb->tstamp; memcpy(__skb->cb, &cb->data, QDISC_CB_PRIV_LEN); + __skb->wire_len = cb->pkt_len; + __skb->gso_segs = skb_shinfo(skb)->gso_segs; } int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr, -- 2.30.2