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

Alexei Starovoitov says:

====================
pull-request: bpf 2019-01-31

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

The main changes are:

1) disable preemption in sender side of socket filters, from Alexei.

2) fix two potential deadlocks in syscall bpf lookup and prog_register,
   from Martin and Alexei.

3) fix BTF to allow typedef on func_proto, from Yonghong.

4) two bpftool fixes, from Jiri and Paolo.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>

MAINTAINERS

@@ -2848,6 +2848,9 @@ F:	include/uapi/linux/if_bonding.h
 BPF (Safe dynamic programs and tools)
 M:	Alexei Starovoitov <ast@kernel.org>
 M:	Daniel Borkmann <daniel@iogearbox.net>
+R:	Martin KaFai Lau <kafai@fb.com>
+R:	Song Liu <songliubraving@fb.com>
+R:	Yonghong Song <yhs@fb.com>
 L:	netdev@vger.kernel.org
 L:	linux-kernel@vger.kernel.org
 T:	git git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git
@@ -2873,6 +2876,8 @@ F:	samples/bpf/
 F:	tools/bpf/
 F:	tools/lib/bpf/
 F:	tools/testing/selftests/bpf/
+K:	bpf
+N:	bpf
 
 BPF JIT for ARM
 M:	Shubham Bansal <illusionist.neo@gmail.com>

include/linux/filter.h

@@ -591,8 +591,8 @@ static inline u8 *bpf_skb_cb(struct sk_buff *skb)
 	return qdisc_skb_cb(skb)->data;
 }
 
-static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
-				       struct sk_buff *skb)
+static inline u32 __bpf_prog_run_save_cb(const struct bpf_prog *prog,
+					 struct sk_buff *skb)
 {
 	u8 *cb_data = bpf_skb_cb(skb);
 	u8 cb_saved[BPF_SKB_CB_LEN];
@@ -611,15 +611,30 @@ static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
 	return res;
 }
 
+static inline u32 bpf_prog_run_save_cb(const struct bpf_prog *prog,
+				       struct sk_buff *skb)
+{
+	u32 res;
+
+	preempt_disable();
+	res = __bpf_prog_run_save_cb(prog, skb);
+	preempt_enable();
+	return res;
+}
+
 static inline u32 bpf_prog_run_clear_cb(const struct bpf_prog *prog,
 					struct sk_buff *skb)
 {
 	u8 *cb_data = bpf_skb_cb(skb);
+	u32 res;
 
 	if (unlikely(prog->cb_access))
 		memset(cb_data, 0, BPF_SKB_CB_LEN);
 
-	return BPF_PROG_RUN(prog, skb);
+	preempt_disable();
+	res = BPF_PROG_RUN(prog, skb);
+	preempt_enable();
+	return res;
 }
 
 static __always_inline u32 bpf_prog_run_xdp(const struct bpf_prog *prog,

kernel/bpf/btf.c

@@ -1459,7 +1459,8 @@ static int btf_modifier_resolve(struct btf_verifier_env *env,
 
 		/* "typedef void new_void", "const void"...etc */
 		if (!btf_type_is_void(next_type) &&
-		    !btf_type_is_fwd(next_type)) {
+		    !btf_type_is_fwd(next_type) &&
+		    !btf_type_is_func_proto(next_type)) {
 			btf_verifier_log_type(env, v->t, "Invalid type_id");
 			return -EINVAL;
 		}

kernel/bpf/cgroup.c

@@ -572,7 +572,7 @@ int __cgroup_bpf_run_filter_skb(struct sock *sk,
 	bpf_compute_and_save_data_end(skb, &saved_data_end);
 
 	ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], skb,
-				 bpf_prog_run_save_cb);
+				 __bpf_prog_run_save_cb);
 	bpf_restore_data_end(skb, saved_data_end);
 	__skb_pull(skb, offset);
 	skb->sk = save_sk;

kernel/bpf/hashtab.c

@@ -686,7 +686,7 @@ static void free_htab_elem(struct bpf_htab *htab, struct htab_elem *l)
 	}
 
 	if (htab_is_prealloc(htab)) {
-		pcpu_freelist_push(&htab->freelist, &l->fnode);
+		__pcpu_freelist_push(&htab->freelist, &l->fnode);
 	} else {
 		atomic_dec(&htab->count);
 		l->htab = htab;
@@ -748,7 +748,7 @@ static struct htab_elem *alloc_htab_elem(struct bpf_htab *htab, void *key,
 		} else {
 			struct pcpu_freelist_node *l;
 
-			l = pcpu_freelist_pop(&htab->freelist);
+			l = __pcpu_freelist_pop(&htab->freelist);
 			if (!l)
 				return ERR_PTR(-E2BIG);
 			l_new = container_of(l, struct htab_elem, fnode);

kernel/bpf/percpu_freelist.c

@@ -28,8 +28,8 @@ void pcpu_freelist_destroy(struct pcpu_freelist *s)
 	free_percpu(s->freelist);
 }
 
-static inline void __pcpu_freelist_push(struct pcpu_freelist_head *head,
-					struct pcpu_freelist_node *node)
+static inline void ___pcpu_freelist_push(struct pcpu_freelist_head *head,
+					 struct pcpu_freelist_node *node)
 {
 	raw_spin_lock(&head->lock);
 	node->next = head->first;
@@ -37,12 +37,22 @@ static inline void __pcpu_freelist_push(struct pcpu_freelist_head *head,
 	raw_spin_unlock(&head->lock);
 }
 
-void pcpu_freelist_push(struct pcpu_freelist *s,
+void __pcpu_freelist_push(struct pcpu_freelist *s,
 			struct pcpu_freelist_node *node)
 {
 	struct pcpu_freelist_head *head = this_cpu_ptr(s->freelist);
 
-	__pcpu_freelist_push(head, node);
+	___pcpu_freelist_push(head, node);
+}
+
+void pcpu_freelist_push(struct pcpu_freelist *s,
+			struct pcpu_freelist_node *node)
+{
+	unsigned long flags;
+
+	local_irq_save(flags);
+	__pcpu_freelist_push(s, node);
+	local_irq_restore(flags);
 }
 
 void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size,
@@ -63,7 +73,7 @@ void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size,
 	for_each_possible_cpu(cpu) {
 again:
 		head = per_cpu_ptr(s->freelist, cpu);
-		__pcpu_freelist_push(head, buf);
+		___pcpu_freelist_push(head, buf);
 		i++;
 		buf += elem_size;
 		if (i == nr_elems)
@@ -74,14 +84,12 @@ void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size,
 	local_irq_restore(flags);
 }
 
-struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s)
+struct pcpu_freelist_node *__pcpu_freelist_pop(struct pcpu_freelist *s)
 {
 	struct pcpu_freelist_head *head;
 	struct pcpu_freelist_node *node;
-	unsigned long flags;
 	int orig_cpu, cpu;
 
-	local_irq_save(flags);
 	orig_cpu = cpu = raw_smp_processor_id();
 	while (1) {
 		head = per_cpu_ptr(s->freelist, cpu);
@@ -89,16 +97,25 @@ struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s)
 		node = head->first;
 		if (node) {
 			head->first = node->next;
-			raw_spin_unlock_irqrestore(&head->lock, flags);
+			raw_spin_unlock(&head->lock);
 			return node;
 		}
 		raw_spin_unlock(&head->lock);
 		cpu = cpumask_next(cpu, cpu_possible_mask);
 		if (cpu >= nr_cpu_ids)
 			cpu = 0;
-		if (cpu == orig_cpu) {
-			local_irq_restore(flags);
+		if (cpu == orig_cpu)
 			return NULL;
-		}
 	}
 }
+
+struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *s)
+{
+	struct pcpu_freelist_node *ret;
+	unsigned long flags;
+
+	local_irq_save(flags);
+	ret = __pcpu_freelist_pop(s);
+	local_irq_restore(flags);
+	return ret;
+}

kernel/bpf/percpu_freelist.h

@@ -22,8 +22,12 @@ struct pcpu_freelist_node {
 	struct pcpu_freelist_node *next;
 };
 
+/* pcpu_freelist_* do spin_lock_irqsave. */
 void pcpu_freelist_push(struct pcpu_freelist *, struct pcpu_freelist_node *);
 struct pcpu_freelist_node *pcpu_freelist_pop(struct pcpu_freelist *);
+/* __pcpu_freelist_* do spin_lock only. caller must disable irqs. */
+void __pcpu_freelist_push(struct pcpu_freelist *, struct pcpu_freelist_node *);
+struct pcpu_freelist_node *__pcpu_freelist_pop(struct pcpu_freelist *);
 void pcpu_freelist_populate(struct pcpu_freelist *s, void *buf, u32 elem_size,
 			    u32 nr_elems);
 int pcpu_freelist_init(struct pcpu_freelist *);

kernel/bpf/syscall.c

@@ -713,8 +713,13 @@ static int map_lookup_elem(union bpf_attr *attr)
 
 	if (bpf_map_is_dev_bound(map)) {
 		err = bpf_map_offload_lookup_elem(map, key, value);
-	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
-		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
+		goto done;
+	}
+
+	preempt_disable();
+	this_cpu_inc(bpf_prog_active);
+	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
+	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
 		err = bpf_percpu_hash_copy(map, key, value);
 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
 		err = bpf_percpu_array_copy(map, key, value);
@@ -744,7 +749,10 @@ static int map_lookup_elem(union bpf_attr *attr)
 		}
 		rcu_read_unlock();
 	}
+	this_cpu_dec(bpf_prog_active);
+	preempt_enable();
 
+done:
 	if (err)
 		goto free_value;
 

kernel/trace/bpf_trace.c

@@ -1204,22 +1204,12 @@ static int __bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *
 
 int bpf_probe_register(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
 {
-	int err;
-
-	mutex_lock(&bpf_event_mutex);
-	err = __bpf_probe_register(btp, prog);
-	mutex_unlock(&bpf_event_mutex);
-	return err;
+	return __bpf_probe_register(btp, prog);
 }
 
 int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog)
 {
-	int err;
-
-	mutex_lock(&bpf_event_mutex);
-	err = tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
-	mutex_unlock(&bpf_event_mutex);
-	return err;
+	return tracepoint_probe_unregister(btp->tp, (void *)btp->bpf_func, prog);
 }
 
 int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,

net/core/filter.c

@@ -4112,10 +4112,12 @@ BPF_CALL_5(bpf_setsockopt, struct bpf_sock_ops_kern *, bpf_sock,
 		/* Only some socketops are supported */
 		switch (optname) {
 		case SO_RCVBUF:
+			val = min_t(u32, val, sysctl_rmem_max);
 			sk->sk_userlocks |= SOCK_RCVBUF_LOCK;
 			sk->sk_rcvbuf = max_t(int, val * 2, SOCK_MIN_RCVBUF);
 			break;
 		case SO_SNDBUF:
+			val = min_t(u32, val, sysctl_wmem_max);
 			sk->sk_userlocks |= SOCK_SNDBUF_LOCK;
 			sk->sk_sndbuf = max_t(int, val * 2, SOCK_MIN_SNDBUF);
 			break;

net/core/skmsg.c

@@ -545,8 +545,7 @@ static void sk_psock_destroy_deferred(struct work_struct *gc)
 	struct sk_psock *psock = container_of(gc, struct sk_psock, gc);
 
 	/* No sk_callback_lock since already detached. */
-	if (psock->parser.enabled)
-		strp_done(&psock->parser.strp);
+	strp_done(&psock->parser.strp);
 
 	cancel_work_sync(&psock->work);
 

tools/bpf/bpftool/common.c

@@ -297,10 +297,8 @@ char *get_fdinfo(int fd, const char *key)
 	snprintf(path, sizeof(path), "/proc/self/fdinfo/%d", fd);
 
 	fdi = fopen(path, "r");
-	if (!fdi) {
-		p_err("can't open fdinfo: %s", strerror(errno));
+	if (!fdi)
 		return NULL;
-	}
 
 	while ((n = getline(&line, &line_n, fdi)) > 0) {
 		char *value;
@@ -313,7 +311,6 @@ char *get_fdinfo(int fd, const char *key)
 
 		value = strchr(line, '\t');
 		if (!value || !value[1]) {
-			p_err("malformed fdinfo!?");
 			free(line);
 			return NULL;
 		}
@@ -326,7 +323,6 @@ char *get_fdinfo(int fd, const char *key)
 		return line;
 	}
 
-	p_err("key '%s' not found in fdinfo", key);
 	free(line);
 	fclose(fdi);
 	return NULL;

tools/bpf/bpftool/map.c

@@ -347,6 +347,20 @@ static char **parse_bytes(char **argv, const char *name, unsigned char *val,
 	return argv + i;
 }
 
+/* on per cpu maps we must copy the provided value on all value instances */
+static void fill_per_cpu_value(struct bpf_map_info *info, void *value)
+{
+	unsigned int i, n, step;
+
+	if (!map_is_per_cpu(info->type))
+		return;
+
+	n = get_possible_cpus();
+	step = round_up(info->value_size, 8);
+	for (i = 1; i < n; i++)
+		memcpy(value + i * step, value, info->value_size);
+}
+
 static int parse_elem(char **argv, struct bpf_map_info *info,
 		      void *key, void *value, __u32 key_size, __u32 value_size,
 		      __u32 *flags, __u32 **value_fd)
@@ -426,6 +440,8 @@ static int parse_elem(char **argv, struct bpf_map_info *info,
 			argv = parse_bytes(argv, "value", value, value_size);
 			if (!argv)
 				return -1;
+
+			fill_per_cpu_value(info, value);
 		}
 
 		return parse_elem(argv, info, key, NULL, key_size, value_size,
@@ -497,10 +513,9 @@ static int show_map_close_json(int fd, struct bpf_map_info *info)
 				jsonw_uint_field(json_wtr, "owner_prog_type",
 						 prog_type);
 		}
-		if (atoi(owner_jited))
-			jsonw_bool_field(json_wtr, "owner_jited", true);
-		else
-			jsonw_bool_field(json_wtr, "owner_jited", false);
+		if (owner_jited)
+			jsonw_bool_field(json_wtr, "owner_jited",
+					 !!atoi(owner_jited));
 
 		free(owner_prog_type);
 		free(owner_jited);
@@ -553,7 +568,8 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info)
 		char *owner_prog_type = get_fdinfo(fd, "owner_prog_type");
 		char *owner_jited = get_fdinfo(fd, "owner_jited");
 
-		printf("\n\t");
+		if (owner_prog_type || owner_jited)
+			printf("\n\t");
 		if (owner_prog_type) {
 			unsigned int prog_type = atoi(owner_prog_type);
 
@@ -563,10 +579,9 @@ static int show_map_close_plain(int fd, struct bpf_map_info *info)
 			else
 				printf("owner_prog_type %d  ", prog_type);
 		}
-		if (atoi(owner_jited))
-			printf("owner jited");
-		else
-			printf("owner not jited");
+		if (owner_jited)
+			printf("owner%s jited",
+			       atoi(owner_jited) ? "" : " not");
 
 		free(owner_prog_type);
 		free(owner_jited);

tools/bpf/bpftool/prog.c

@@ -78,13 +78,14 @@ static void print_boot_time(__u64 nsecs, char *buf, unsigned int size)
 
 static int prog_fd_by_tag(unsigned char *tag)
 {
-	struct bpf_prog_info info = {};
-	__u32 len = sizeof(info);
 	unsigned int id = 0;
 	int err;
 	int fd;
 
 	while (true) {
+		struct bpf_prog_info info = {};
+		__u32 len = sizeof(info);
+
 		err = bpf_prog_get_next_id(id, &id);
 		if (err) {
 			p_err("%s", strerror(errno));

tools/testing/selftests/bpf/bpf_util.h

@@ -13,7 +13,7 @@ static inline unsigned int bpf_num_possible_cpus(void)
 	unsigned int start, end, possible_cpus = 0;
 	char buff[128];
 	FILE *fp;
-	int n;
+	int len, n, i, j = 0;
 
 	fp = fopen(fcpu, "r");
 	if (!fp) {
@@ -21,17 +21,27 @@ static inline unsigned int bpf_num_possible_cpus(void)
 		exit(1);
 	}
 
-	while (fgets(buff, sizeof(buff), fp)) {
-		n = sscanf(buff, "%u-%u", &start, &end);
-		if (n == 0) {
-			printf("Failed to retrieve # possible CPUs!\n");
-			exit(1);
-		} else if (n == 1) {
-			end = start;
+	if (!fgets(buff, sizeof(buff), fp)) {
+		printf("Failed to read %s!\n", fcpu);
+		exit(1);
+	}
+
+	len = strlen(buff);
+	for (i = 0; i <= len; i++) {
+		if (buff[i] == ',' || buff[i] == '\0') {
+			buff[i] = '\0';
+			n = sscanf(&buff[j], "%u-%u", &start, &end);
+			if (n <= 0) {
+				printf("Failed to retrieve # possible CPUs!\n");
+				exit(1);
+			} else if (n == 1) {
+				end = start;
+			}
+			possible_cpus += end - start + 1;
+			j = i + 1;
 		}
-		possible_cpus = start == 0 ? end + 1 : 0;
-		break;
 	}
+
 	fclose(fp);
 
 	return possible_cpus;

tools/testing/selftests/bpf/test_btf.c

@@ -1881,13 +1881,12 @@ static struct btf_raw_test raw_tests[] = {
 },
 
 {
-	.descr = "func proto (CONST=>TYPEDEF=>FUNC_PROTO)",
+	.descr = "func proto (TYPEDEF=>FUNC_PROTO)",
 	.raw_types = {
 		BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4),	/* [1] */
 		BTF_TYPE_INT_ENC(0, 0, 0, 32, 4),		/* [2] */
-		BTF_CONST_ENC(4),				/* [3] */
-		BTF_TYPEDEF_ENC(NAME_TBD, 5),			/* [4] */
-		BTF_FUNC_PROTO_ENC(0, 2),			/* [5] */
+		BTF_TYPEDEF_ENC(NAME_TBD, 4),			/* [3] */
+		BTF_FUNC_PROTO_ENC(0, 2),			/* [4] */
 			BTF_FUNC_PROTO_ARG_ENC(0, 1),
 			BTF_FUNC_PROTO_ARG_ENC(0, 2),
 		BTF_END_RAW,
@@ -1901,8 +1900,6 @@ static struct btf_raw_test raw_tests[] = {
 	.key_type_id = 1,
 	.value_type_id = 1,
 	.max_entries = 4,
-	.btf_load_err = true,
-	.err_str = "Invalid type_id",
 },
 
 {