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

Alexei Starovoitov says:

====================
pull-request: bpf-next 2020-02-28

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

We've added 41 non-merge commits during the last 7 day(s) which contain
a total of 49 files changed, 1383 insertions(+), 499 deletions(-).

The main changes are:

1) BPF and Real-Time nicely co-exist.

2) bpftool feature improvements.

3) retrieve bpf_sk_storage via INET_DIAG.
====================

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

3 files changed, 280 insertions, 15 deletions

diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c
index 427cfbc0d50d..756b63b6f7b3 100644
--- a/net/core/bpf_sk_storage.c
+++ b/net/core/bpf_sk_storage.c
@@ -8,6 +8,7 @@
 #include <linux/bpf.h>
 #include <net/bpf_sk_storage.h>
 #include <net/sock.h>
+#include <uapi/linux/sock_diag.h>
 #include <uapi/linux/btf.h>
 
 static atomic_t cache_idx;
@@ -606,6 +607,14 @@ static void bpf_sk_storage_map_free(struct bpf_map *map)
 	kfree(map);
 }
 
+/* U16_MAX is much more than enough for sk local storage
+ * considering a tcp_sock is ~2k.
+ */
+#define MAX_VALUE_SIZE							\
+	min_t(u32,							\
+	      (KMALLOC_MAX_SIZE - MAX_BPF_STACK - sizeof(struct bpf_sk_storage_elem)), \
+	      (U16_MAX - sizeof(struct bpf_sk_storage_elem)))
+
 static int bpf_sk_storage_map_alloc_check(union bpf_attr *attr)
 {
 	if (attr->map_flags & ~SK_STORAGE_CREATE_FLAG_MASK ||
@@ -619,12 +628,7 @@ static int bpf_sk_storage_map_alloc_check(union bpf_attr *attr)
 	if (!capable(CAP_SYS_ADMIN))
 		return -EPERM;
 
-	if (attr->value_size >= KMALLOC_MAX_SIZE -
-	    MAX_BPF_STACK - sizeof(struct bpf_sk_storage_elem) ||
-	    /* U16_MAX is much more than enough for sk local storage
-	     * considering a tcp_sock is ~2k.
-	     */
-	    attr->value_size > U16_MAX - sizeof(struct bpf_sk_storage_elem))
+	if (attr->value_size > MAX_VALUE_SIZE)
 		return -E2BIG;
 
 	return 0;
@@ -910,3 +914,270 @@ const struct bpf_func_proto bpf_sk_storage_delete_proto = {
 	.arg1_type	= ARG_CONST_MAP_PTR,
 	.arg2_type	= ARG_PTR_TO_SOCKET,
 };
+
+struct bpf_sk_storage_diag {
+	u32 nr_maps;
+	struct bpf_map *maps[];
+};
+
+/* The reply will be like:
+ * INET_DIAG_BPF_SK_STORAGES (nla_nest)
+ *	SK_DIAG_BPF_STORAGE (nla_nest)
+ *		SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
+ *		SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
+ *	SK_DIAG_BPF_STORAGE (nla_nest)
+ *		SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
+ *		SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
+ *	....
+ */
+static int nla_value_size(u32 value_size)
+{
+	/* SK_DIAG_BPF_STORAGE (nla_nest)
+	 *	SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
+	 *	SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
+	 */
+	return nla_total_size(0) + nla_total_size(sizeof(u32)) +
+		nla_total_size_64bit(value_size);
+}
+
+void bpf_sk_storage_diag_free(struct bpf_sk_storage_diag *diag)
+{
+	u32 i;
+
+	if (!diag)
+		return;
+
+	for (i = 0; i < diag->nr_maps; i++)
+		bpf_map_put(diag->maps[i]);
+
+	kfree(diag);
+}
+EXPORT_SYMBOL_GPL(bpf_sk_storage_diag_free);
+
+static bool diag_check_dup(const struct bpf_sk_storage_diag *diag,
+			   const struct bpf_map *map)
+{
+	u32 i;
+
+	for (i = 0; i < diag->nr_maps; i++) {
+		if (diag->maps[i] == map)
+			return true;
+	}
+
+	return false;
+}
+
+struct bpf_sk_storage_diag *
+bpf_sk_storage_diag_alloc(const struct nlattr *nla_stgs)
+{
+	struct bpf_sk_storage_diag *diag;
+	struct nlattr *nla;
+	u32 nr_maps = 0;
+	int rem, err;
+
+	/* bpf_sk_storage_map is currently limited to CAP_SYS_ADMIN as
+	 * the map_alloc_check() side also does.
+	 */
+	if (!capable(CAP_SYS_ADMIN))
+		return ERR_PTR(-EPERM);
+
+	nla_for_each_nested(nla, nla_stgs, rem) {
+		if (nla_type(nla) == SK_DIAG_BPF_STORAGE_REQ_MAP_FD)
+			nr_maps++;
+	}
+
+	diag = kzalloc(sizeof(*diag) + sizeof(diag->maps[0]) * nr_maps,
+		       GFP_KERNEL);
+	if (!diag)
+		return ERR_PTR(-ENOMEM);
+
+	nla_for_each_nested(nla, nla_stgs, rem) {
+		struct bpf_map *map;
+		int map_fd;
+
+		if (nla_type(nla) != SK_DIAG_BPF_STORAGE_REQ_MAP_FD)
+			continue;
+
+		map_fd = nla_get_u32(nla);
+		map = bpf_map_get(map_fd);
+		if (IS_ERR(map)) {
+			err = PTR_ERR(map);
+			goto err_free;
+		}
+		if (map->map_type != BPF_MAP_TYPE_SK_STORAGE) {
+			bpf_map_put(map);
+			err = -EINVAL;
+			goto err_free;
+		}
+		if (diag_check_dup(diag, map)) {
+			bpf_map_put(map);
+			err = -EEXIST;
+			goto err_free;
+		}
+		diag->maps[diag->nr_maps++] = map;
+	}
+
+	return diag;
+
+err_free:
+	bpf_sk_storage_diag_free(diag);
+	return ERR_PTR(err);
+}
+EXPORT_SYMBOL_GPL(bpf_sk_storage_diag_alloc);
+
+static int diag_get(struct bpf_sk_storage_data *sdata, struct sk_buff *skb)
+{
+	struct nlattr *nla_stg, *nla_value;
+	struct bpf_sk_storage_map *smap;
+
+	/* It cannot exceed max nlattr's payload */
+	BUILD_BUG_ON(U16_MAX - NLA_HDRLEN < MAX_VALUE_SIZE);
+
+	nla_stg = nla_nest_start(skb, SK_DIAG_BPF_STORAGE);
+	if (!nla_stg)
+		return -EMSGSIZE;
+
+	smap = rcu_dereference(sdata->smap);
+	if (nla_put_u32(skb, SK_DIAG_BPF_STORAGE_MAP_ID, smap->map.id))
+		goto errout;
+
+	nla_value = nla_reserve_64bit(skb, SK_DIAG_BPF_STORAGE_MAP_VALUE,
+				      smap->map.value_size,
+				      SK_DIAG_BPF_STORAGE_PAD);
+	if (!nla_value)
+		goto errout;
+
+	if (map_value_has_spin_lock(&smap->map))
+		copy_map_value_locked(&smap->map, nla_data(nla_value),
+				      sdata->data, true);
+	else
+		copy_map_value(&smap->map, nla_data(nla_value), sdata->data);
+
+	nla_nest_end(skb, nla_stg);
+	return 0;
+
+errout:
+	nla_nest_cancel(skb, nla_stg);
+	return -EMSGSIZE;
+}
+
+static int bpf_sk_storage_diag_put_all(struct sock *sk, struct sk_buff *skb,
+				       int stg_array_type,
+				       unsigned int *res_diag_size)
+{
+	/* stg_array_type (e.g. INET_DIAG_BPF_SK_STORAGES) */
+	unsigned int diag_size = nla_total_size(0);
+	struct bpf_sk_storage *sk_storage;
+	struct bpf_sk_storage_elem *selem;
+	struct bpf_sk_storage_map *smap;
+	struct nlattr *nla_stgs;
+	unsigned int saved_len;
+	int err = 0;
+
+	rcu_read_lock();
+
+	sk_storage = rcu_dereference(sk->sk_bpf_storage);
+	if (!sk_storage || hlist_empty(&sk_storage->list)) {
+		rcu_read_unlock();
+		return 0;
+	}
+
+	nla_stgs = nla_nest_start(skb, stg_array_type);
+	if (!nla_stgs)
+		/* Continue to learn diag_size */
+		err = -EMSGSIZE;
+
+	saved_len = skb->len;
+	hlist_for_each_entry_rcu(selem, &sk_storage->list, snode) {
+		smap = rcu_dereference(SDATA(selem)->smap);
+		diag_size += nla_value_size(smap->map.value_size);
+
+		if (nla_stgs && diag_get(SDATA(selem), skb))
+			/* Continue to learn diag_size */
+			err = -EMSGSIZE;
+	}
+
+	rcu_read_unlock();
+
+	if (nla_stgs) {
+		if (saved_len == skb->len)
+			nla_nest_cancel(skb, nla_stgs);
+		else
+			nla_nest_end(skb, nla_stgs);
+	}
+
+	if (diag_size == nla_total_size(0)) {
+		*res_diag_size = 0;
+		return 0;
+	}
+
+	*res_diag_size = diag_size;
+	return err;
+}
+
+int bpf_sk_storage_diag_put(struct bpf_sk_storage_diag *diag,
+			    struct sock *sk, struct sk_buff *skb,
+			    int stg_array_type,
+			    unsigned int *res_diag_size)
+{
+	/* stg_array_type (e.g. INET_DIAG_BPF_SK_STORAGES) */
+	unsigned int diag_size = nla_total_size(0);
+	struct bpf_sk_storage *sk_storage;
+	struct bpf_sk_storage_data *sdata;
+	struct nlattr *nla_stgs;
+	unsigned int saved_len;
+	int err = 0;
+	u32 i;
+
+	*res_diag_size = 0;
+
+	/* No map has been specified.  Dump all. */
+	if (!diag->nr_maps)
+		return bpf_sk_storage_diag_put_all(sk, skb, stg_array_type,
+						   res_diag_size);
+
+	rcu_read_lock();
+	sk_storage = rcu_dereference(sk->sk_bpf_storage);
+	if (!sk_storage || hlist_empty(&sk_storage->list)) {
+		rcu_read_unlock();
+		return 0;
+	}
+
+	nla_stgs = nla_nest_start(skb, stg_array_type);
+	if (!nla_stgs)
+		/* Continue to learn diag_size */
+		err = -EMSGSIZE;
+
+	saved_len = skb->len;
+	for (i = 0; i < diag->nr_maps; i++) {
+		sdata = __sk_storage_lookup(sk_storage,
+				(struct bpf_sk_storage_map *)diag->maps[i],
+				false);
+
+		if (!sdata)
+			continue;
+
+		diag_size += nla_value_size(diag->maps[i]->value_size);
+
+		if (nla_stgs && diag_get(sdata, skb))
+			/* Continue to learn diag_size */
+			err = -EMSGSIZE;
+	}
+	rcu_read_unlock();
+
+	if (nla_stgs) {
+		if (saved_len == skb->len)
+			nla_nest_cancel(skb, nla_stgs);
+		else
+			nla_nest_end(skb, nla_stgs);
+	}
+
+	if (diag_size == nla_total_size(0)) {
+		*res_diag_size = 0;
+		return 0;
+	}
+
+	*res_diag_size = diag_size;
+	return err;
+}
+EXPORT_SYMBOL_GPL(bpf_sk_storage_diag_put);
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index a1670dff0629..3eff84824c8b 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -920,9 +920,7 @@ bool bpf_flow_dissect(struct bpf_prog *prog, struct bpf_flow_dissector *ctx,
 		     (int)FLOW_DISSECTOR_F_STOP_AT_ENCAP);
 	flow_keys->flags = flags;
 
-	preempt_disable();
-	result = BPF_PROG_RUN(prog, ctx);
-	preempt_enable();
+	result = bpf_prog_run_pin_on_cpu(prog, ctx);
 
 	flow_keys->nhoff = clamp_t(u16, flow_keys->nhoff, nhoff, hlen);
 	flow_keys->thoff = clamp_t(u16, flow_keys->thoff,
diff --git a/net/core/skmsg.c b/net/core/skmsg.c
index eeb28cb85664..c479372f2cd2 100644
--- a/net/core/skmsg.c
+++ b/net/core/skmsg.c
@@ -628,7 +628,6 @@ int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
 	struct bpf_prog *prog;
 	int ret;
 
-	preempt_disable();
 	rcu_read_lock();
 	prog = READ_ONCE(psock->progs.msg_parser);
 	if (unlikely(!prog)) {
@@ -638,7 +637,7 @@ int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
 
 	sk_msg_compute_data_pointers(msg);
 	msg->sk = sk;
-	ret = BPF_PROG_RUN(prog, msg);
+	ret = bpf_prog_run_pin_on_cpu(prog, msg);
 	ret = sk_psock_map_verd(ret, msg->sk_redir);
 	psock->apply_bytes = msg->apply_bytes;
 	if (ret == __SK_REDIRECT) {
@@ -653,7 +652,6 @@ int sk_psock_msg_verdict(struct sock *sk, struct sk_psock *psock,
 	}
 out:
 	rcu_read_unlock();
-	preempt_enable();
 	return ret;
 }
 EXPORT_SYMBOL_GPL(sk_psock_msg_verdict);
@@ -665,9 +663,7 @@ static int sk_psock_bpf_run(struct sk_psock *psock, struct bpf_prog *prog,
 
 	skb->sk = psock->sk;
 	bpf_compute_data_end_sk_skb(skb);
-	preempt_disable();
-	ret = BPF_PROG_RUN(prog, skb);
-	preempt_enable();
+	ret = bpf_prog_run_pin_on_cpu(prog, skb);
 	/* strparser clones the skb before handing it to a upper layer,
 	 * meaning skb_orphan has been called. We NULL sk on the way out
 	 * to ensure we don't trigger a BUG_ON() in skb/sk operations