From 04686ef299db5ff299bfc5a4504b189e46842078 Mon Sep 17 00:00:00 2001 From: John Fastabend Date: Tue, 31 Oct 2017 19:17:31 -0700 Subject: [PATCH] bpf: remove SK_REDIRECT from UAPI Now that SK_REDIRECT is no longer a valid return code. Remove it from the UAPI completely. Then do a namespace remapping internal to sockmap so SK_REDIRECT is no longer externally visible. Patchs primary change is to do a namechange from SK_REDIRECT to __SK_REDIRECT Reported-by: Alexei Starovoitov Signed-off-by: John Fastabend Signed-off-by: David S. Miller --- include/uapi/linux/bpf.h | 1 - kernel/bpf/sockmap.c | 16 ++++++++++++---- tools/include/uapi/linux/bpf.h | 3 +-- 3 files changed, 13 insertions(+), 7 deletions(-) diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h index 0d7948ce2128..7bf4c750dd3a 100644 --- a/include/uapi/linux/bpf.h +++ b/include/uapi/linux/bpf.h @@ -788,7 +788,6 @@ struct xdp_md { enum sk_action { SK_DROP = 0, SK_PASS, - SK_REDIRECT, }; #define BPF_TAG_SIZE 8 diff --git a/kernel/bpf/sockmap.c b/kernel/bpf/sockmap.c index 66f00a2b27f4..dbd7b322a86b 100644 --- a/kernel/bpf/sockmap.c +++ b/kernel/bpf/sockmap.c @@ -101,13 +101,19 @@ static inline void bpf_compute_data_end_sk_skb(struct sk_buff *skb) TCP_SKB_CB(skb)->bpf.data_end = skb->data + skb_headlen(skb); } +enum __sk_action { + __SK_DROP = 0, + __SK_PASS, + __SK_REDIRECT, +}; + static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb) { struct bpf_prog *prog = READ_ONCE(psock->bpf_verdict); int rc; if (unlikely(!prog)) - return SK_DROP; + return __SK_DROP; skb_orphan(skb); /* We need to ensure that BPF metadata for maps is also cleared @@ -122,8 +128,10 @@ static int smap_verdict_func(struct smap_psock *psock, struct sk_buff *skb) preempt_enable(); skb->sk = NULL; + /* Moving return codes from UAPI namespace into internal namespace */ return rc == SK_PASS ? - (TCP_SKB_CB(skb)->bpf.map ? SK_REDIRECT : SK_PASS) : SK_DROP; + (TCP_SKB_CB(skb)->bpf.map ? __SK_REDIRECT : __SK_PASS) : + __SK_DROP; } static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb) @@ -133,7 +141,7 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb) rc = smap_verdict_func(psock, skb); switch (rc) { - case SK_REDIRECT: + case __SK_REDIRECT: sk = do_sk_redirect_map(skb); if (likely(sk)) { struct smap_psock *peer = smap_psock_sk(sk); @@ -149,7 +157,7 @@ static void smap_do_verdict(struct smap_psock *psock, struct sk_buff *skb) } } /* Fall through and free skb otherwise */ - case SK_DROP: + case __SK_DROP: default: kfree_skb(skb); } diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h index c174971afbe6..01cc7ba39924 100644 --- a/tools/include/uapi/linux/bpf.h +++ b/tools/include/uapi/linux/bpf.h @@ -576,7 +576,7 @@ union bpf_attr { * @map: pointer to sockmap * @key: key to lookup sock in map * @flags: reserved for future use - * Return: SK_REDIRECT + * Return: SK_PASS * * int bpf_sock_map_update(skops, map, key, flags) * @skops: pointer to bpf_sock_ops @@ -789,7 +789,6 @@ struct xdp_md { enum sk_action { SK_DROP = 0, SK_PASS, - SK_REDIRECT, }; #define BPF_TAG_SIZE 8 -- 2.20.1