Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next

Daniel Borkmann says:

====================
pull-request: bpf-next 2018-08-07

The following pull-request contains BPF updates for your *net-next* tree.

The main changes are:

1) Add cgroup local storage for BPF programs, which provides a fast
   accessible memory for storing various per-cgroup data like number
   of transmitted packets, etc, from Roman.

2) Support bpf_get_socket_cookie() BPF helper in several more program
   types that have a full socket available, from Andrey.

3) Significantly improve the performance of perf events which are
   reported from BPF offload. Also convert a couple of BPF AF_XDP
   samples overto use libbpf, both from Jakub.

4) seg6local LWT provides the End.DT6 action, which allows to
   decapsulate an outer IPv6 header containing a Segment Routing Header.
   Adds this action now to the seg6local BPF interface, from Mathieu.

5) Do not mark dst register as unbounded in MOV64 instruction when
   both src and dst register are the same, from Arthur.

6) Define u_smp_rmb() and u_smp_wmb() to their respective barrier
   instructions on arm64 for the AF_XDP sample code, from Brian.

7) Convert the tcp_client.py and tcp_server.py BPF selftest scripts
   over from Python 2 to Python 3, from Jeremy.

8) Enable BTF build flags to the BPF sample code Makefile, from Taeung.

9) Remove an unnecessary rcu_read_lock() in run_lwt_bpf(), from Taehee.

10) Several improvements to the README.rst from the BPF documentation
    to make it more consistent with RST format, from Tobin.

11) Replace all occurrences of strerror() by calls to strerror_r()
    in libbpf and fix a FORTIFY_SOURCE build error along with it,
    from Thomas.

12) Fix a bug in bpftool's get_btf() function to correctly propagate
    an error via PTR_ERR(), from Yue.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 109 insertions, 32 deletions

diff --git a/net/core/filter.c b/net/core/filter.c
index 7509bb7f0694..587bbfbd7db3 100644
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -3814,6 +3814,30 @@ static const struct bpf_func_proto bpf_get_socket_cookie_proto = {
 	.arg1_type      = ARG_PTR_TO_CTX,
 };
 
+BPF_CALL_1(bpf_get_socket_cookie_sock_addr, struct bpf_sock_addr_kern *, ctx)
+{
+	return sock_gen_cookie(ctx->sk);
+}
+
+static const struct bpf_func_proto bpf_get_socket_cookie_sock_addr_proto = {
+	.func		= bpf_get_socket_cookie_sock_addr,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+};
+
+BPF_CALL_1(bpf_get_socket_cookie_sock_ops, struct bpf_sock_ops_kern *, ctx)
+{
+	return sock_gen_cookie(ctx->sk);
+}
+
+static const struct bpf_func_proto bpf_get_socket_cookie_sock_ops_proto = {
+	.func		= bpf_get_socket_cookie_sock_ops,
+	.gpl_only	= false,
+	.ret_type	= RET_INTEGER,
+	.arg1_type	= ARG_PTR_TO_CTX,
+};
+
 BPF_CALL_1(bpf_get_socket_uid, struct sk_buff *, skb)
 {
 	struct sock *sk = sk_to_full_sk(skb->sk);
@@ -4544,26 +4568,28 @@ BPF_CALL_4(bpf_lwt_seg6_store_bytes, struct sk_buff *, skb, u32, offset,
 {
 	struct seg6_bpf_srh_state *srh_state =
 		this_cpu_ptr(&seg6_bpf_srh_states);
+	struct ipv6_sr_hdr *srh = srh_state->srh;
 	void *srh_tlvs, *srh_end, *ptr;
-	struct ipv6_sr_hdr *srh;
 	int srhoff = 0;
 
-	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+	if (srh == NULL)
 		return -EINVAL;
 
-	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
 	srh_tlvs = (void *)((char *)srh + ((srh->first_segment + 1) << 4));
 	srh_end = (void *)((char *)srh + sizeof(*srh) + srh_state->hdrlen);
 
 	ptr = skb->data + offset;
 	if (ptr >= srh_tlvs && ptr + len <= srh_end)
-		srh_state->valid = 0;
+		srh_state->valid = false;
 	else if (ptr < (void *)&srh->flags ||
 		 ptr + len > (void *)&srh->segments)
 		return -EFAULT;
 
 	if (unlikely(bpf_try_make_writable(skb, offset + len)))
 		return -EFAULT;
+	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+		return -EINVAL;
+	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
 
 	memcpy(skb->data + offset, from, len);
 	return 0;
@@ -4579,52 +4605,78 @@ static const struct bpf_func_proto bpf_lwt_seg6_store_bytes_proto = {
 	.arg4_type	= ARG_CONST_SIZE
 };
 
-BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
-	   u32, action, void *, param, u32, param_len)
+static void bpf_update_srh_state(struct sk_buff *skb)
 {
 	struct seg6_bpf_srh_state *srh_state =
 		this_cpu_ptr(&seg6_bpf_srh_states);
-	struct ipv6_sr_hdr *srh;
 	int srhoff = 0;
-	int err;
-
-	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
-		return -EINVAL;
-	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
 
-	if (!srh_state->valid) {
-		if (unlikely((srh_state->hdrlen & 7) != 0))
-			return -EBADMSG;
-
-		srh->hdrlen = (u8)(srh_state->hdrlen >> 3);
-		if (unlikely(!seg6_validate_srh(srh, (srh->hdrlen + 1) << 3)))
-			return -EBADMSG;
-
-		srh_state->valid = 1;
+	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0) {
+		srh_state->srh = NULL;
+	} else {
+		srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
+		srh_state->hdrlen = srh_state->srh->hdrlen << 3;
+		srh_state->valid = true;
 	}
+}
+
+BPF_CALL_4(bpf_lwt_seg6_action, struct sk_buff *, skb,
+	   u32, action, void *, param, u32, param_len)
+{
+	struct seg6_bpf_srh_state *srh_state =
+		this_cpu_ptr(&seg6_bpf_srh_states);
+	int hdroff = 0;
+	int err;
 
 	switch (action) {
 	case SEG6_LOCAL_ACTION_END_X:
+		if (!seg6_bpf_has_valid_srh(skb))
+			return -EBADMSG;
 		if (param_len != sizeof(struct in6_addr))
 			return -EINVAL;
 		return seg6_lookup_nexthop(skb, (struct in6_addr *)param, 0);
 	case SEG6_LOCAL_ACTION_END_T:
+		if (!seg6_bpf_has_valid_srh(skb))
+			return -EBADMSG;
 		if (param_len != sizeof(int))
 			return -EINVAL;
 		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
+	case SEG6_LOCAL_ACTION_END_DT6:
+		if (!seg6_bpf_has_valid_srh(skb))
+			return -EBADMSG;
+		if (param_len != sizeof(int))
+			return -EINVAL;
+
+		if (ipv6_find_hdr(skb, &hdroff, IPPROTO_IPV6, NULL, NULL) < 0)
+			return -EBADMSG;
+		if (!pskb_pull(skb, hdroff))
+			return -EBADMSG;
+
+		skb_postpull_rcsum(skb, skb_network_header(skb), hdroff);
+		skb_reset_network_header(skb);
+		skb_reset_transport_header(skb);
+		skb->encapsulation = 0;
+
+		bpf_compute_data_pointers(skb);
+		bpf_update_srh_state(skb);
+		return seg6_lookup_nexthop(skb, NULL, *(int *)param);
 	case SEG6_LOCAL_ACTION_END_B6:
+		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
+			return -EBADMSG;
 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6_INLINE,
 					  param, param_len);
 		if (!err)
-			srh_state->hdrlen =
-				((struct ipv6_sr_hdr *)param)->hdrlen << 3;
+			bpf_update_srh_state(skb);
+
 		return err;
 	case SEG6_LOCAL_ACTION_END_B6_ENCAP:
+		if (srh_state->srh && !seg6_bpf_has_valid_srh(skb))
+			return -EBADMSG;
 		err = bpf_push_seg6_encap(skb, BPF_LWT_ENCAP_SEG6,
 					  param, param_len);
 		if (!err)
-			srh_state->hdrlen =
-				((struct ipv6_sr_hdr *)param)->hdrlen << 3;
+			bpf_update_srh_state(skb);
+
 		return err;
 	default:
 		return -EINVAL;
@@ -4646,15 +4698,14 @@ BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
 {
 	struct seg6_bpf_srh_state *srh_state =
 		this_cpu_ptr(&seg6_bpf_srh_states);
+	struct ipv6_sr_hdr *srh = srh_state->srh;
 	void *srh_end, *srh_tlvs, *ptr;
-	struct ipv6_sr_hdr *srh;
 	struct ipv6hdr *hdr;
 	int srhoff = 0;
 	int ret;
 
-	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+	if (unlikely(srh == NULL))
 		return -EINVAL;
-	srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
 
 	srh_tlvs = (void *)((unsigned char *)srh + sizeof(*srh) +
 			((srh->first_segment + 1) << 4));
@@ -4684,8 +4735,11 @@ BPF_CALL_3(bpf_lwt_seg6_adjust_srh, struct sk_buff *, skb, u32, offset,
 	hdr = (struct ipv6hdr *)skb->data;
 	hdr->payload_len = htons(skb->len - sizeof(struct ipv6hdr));
 
+	if (ipv6_find_hdr(skb, &srhoff, IPPROTO_ROUTING, NULL, NULL) < 0)
+		return -EINVAL;
+	srh_state->srh = (struct ipv6_sr_hdr *)(skb->data + srhoff);
 	srh_state->hdrlen += len;
-	srh_state->valid = 0;
+	srh_state->valid = false;
 	return 0;
 }
 
@@ -4768,6 +4822,8 @@ sock_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 	 */
 	case BPF_FUNC_get_current_uid_gid:
 		return &bpf_get_current_uid_gid_proto;
+	case BPF_FUNC_get_local_storage:
+		return &bpf_get_local_storage_proto;
 	default:
 		return bpf_base_func_proto(func_id);
 	}
@@ -4790,6 +4846,10 @@ sock_addr_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		default:
 			return NULL;
 		}
+	case BPF_FUNC_get_socket_cookie:
+		return &bpf_get_socket_cookie_sock_addr_proto;
+	case BPF_FUNC_get_local_storage:
+		return &bpf_get_local_storage_proto;
 	default:
 		return bpf_base_func_proto(func_id);
 	}
@@ -4813,6 +4873,17 @@ sk_filter_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 }
 
 static const struct bpf_func_proto *
+cg_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+	switch (func_id) {
+	case BPF_FUNC_get_local_storage:
+		return &bpf_get_local_storage_proto;
+	default:
+		return sk_filter_func_proto(func_id, prog);
+	}
+}
+
+static const struct bpf_func_proto *
 tc_cls_act_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 {
 	switch (func_id) {
@@ -4932,6 +5003,10 @@ sock_ops_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_sock_map_update_proto;
 	case BPF_FUNC_sock_hash_update:
 		return &bpf_sock_hash_update_proto;
+	case BPF_FUNC_get_socket_cookie:
+		return &bpf_get_socket_cookie_sock_ops_proto;
+	case BPF_FUNC_get_local_storage:
+		return &bpf_get_local_storage_proto;
 	default:
 		return bpf_base_func_proto(func_id);
 	}
@@ -4951,6 +5026,8 @@ sk_msg_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_msg_cork_bytes_proto;
 	case BPF_FUNC_msg_pull_data:
 		return &bpf_msg_pull_data_proto;
+	case BPF_FUNC_get_local_storage:
+		return &bpf_get_local_storage_proto;
 	default:
 		return bpf_base_func_proto(func_id);
 	}
@@ -4978,6 +5055,8 @@ sk_skb_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
 		return &bpf_sk_redirect_map_proto;
 	case BPF_FUNC_sk_redirect_hash:
 		return &bpf_sk_redirect_hash_proto;
+	case BPF_FUNC_get_local_storage:
+		return &bpf_get_local_storage_proto;
 	default:
 		return bpf_base_func_proto(func_id);
 	}
@@ -6782,7 +6861,7 @@ const struct bpf_prog_ops xdp_prog_ops = {
 };
 
 const struct bpf_verifier_ops cg_skb_verifier_ops = {
-	.get_func_proto		= sk_filter_func_proto,
+	.get_func_proto		= cg_skb_func_proto,
 	.is_valid_access	= sk_filter_is_valid_access,
 	.convert_ctx_access	= bpf_convert_ctx_access,
 };
diff --git a/net/core/lwt_bpf.c b/net/core/lwt_bpf.c
index e45098593dc0..3e85437f7106 100644
--- a/net/core/lwt_bpf.c
+++ b/net/core/lwt_bpf.c
@@ -50,10 +50,8 @@ static int run_lwt_bpf(struct sk_buff *skb, struct bpf_lwt_prog *lwt,
 	 * mixing with BH RCU lock doesn't work.
 	 */
 	preempt_disable();
-	rcu_read_lock();
 	bpf_compute_data_pointers(skb);
 	ret = bpf_prog_run_save_cb(lwt->prog, skb);
-	rcu_read_unlock();
 
 	switch (ret) {
 	case BPF_OK: