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

Alexei Starovoitov says:

====================
pull-request: bpf 2019-12-05

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

We've added 6 non-merge commits during the last 1 day(s) which contain
a total of 14 files changed, 116 insertions(+), 37 deletions(-).

The main changes are:

1) three selftests fixes, from Stanislav.

2) one samples fix, from Jesper.

3) one verifier fix, from Yonghong.
====================

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

kernel/bpf/verifier.c

@@ -9636,7 +9636,10 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
 				ret = -EINVAL;
 				goto out;
 			}
-			addr = (long) tgt_prog->aux->func[subprog]->bpf_func;
+			if (subprog == 0)
+				addr = (long) tgt_prog->bpf_func;
+			else
+				addr = (long) tgt_prog->aux->func[subprog]->bpf_func;
 		} else {
 			addr = kallsyms_lookup_name(tname);
 			if (!addr) {

samples/bpf/xdp_rxq_info_user.c

@@ -489,9 +489,9 @@ int main(int argc, char **argv)
 	if (bpf_prog_load_xattr(&prog_load_attr, &obj, &prog_fd))
 		return EXIT_FAIL;
 
-	map = bpf_map__next(NULL, obj);
-	stats_global_map = bpf_map__next(map, obj);
-	rx_queue_index_map = bpf_map__next(stats_global_map, obj);
+	map =  bpf_object__find_map_by_name(obj, "config_map");
+	stats_global_map = bpf_object__find_map_by_name(obj, "stats_global_map");
+	rx_queue_index_map = bpf_object__find_map_by_name(obj, "rx_queue_index_map");
 	if (!map || !stats_global_map || !rx_queue_index_map) {
 		printf("finding a map in obj file failed\n");
 		return EXIT_FAIL;

tools/lib/bpf/.gitignore

@@ -1,7 +1,6 @@
 libbpf_version.h
 libbpf.pc
 FEATURE-DUMP.libbpf
-test_libbpf
 libbpf.so.*
 TAGS
 tags

tools/lib/bpf/Makefile

@@ -152,7 +152,7 @@ GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN_SHARED) | \
 VERSIONED_SYM_COUNT = $(shell readelf -s --wide $(OUTPUT)libbpf.so | \
 			      grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)
 
-CMD_TARGETS = $(LIB_TARGET) $(PC_FILE) $(OUTPUT)test_libbpf
+CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)
 
 all: fixdep
 	$(Q)$(MAKE) all_cmd
@@ -196,9 +196,6 @@ $(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED)
 $(OUTPUT)libbpf.a: $(BPF_IN_STATIC)
 	$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
 
-$(OUTPUT)test_libbpf: test_libbpf.c $(OUTPUT)libbpf.a
-	$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $(INCLUDES) $^ -lelf -o $@
-
 $(OUTPUT)libbpf.pc:
 	$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
 		-e "s|@LIBDIR@|$(libdir_SQ)|" \

tools/testing/selftests/bpf/.gitignore

@@ -37,5 +37,6 @@ libbpf.so.*
 test_hashmap
 test_btf_dump
 xdping
+test_cpp
 /no_alu32
 /bpf_gcc

tools/testing/selftests/bpf/Makefile

@@ -71,7 +71,7 @@ TEST_PROGS_EXTENDED := with_addr.sh \
 # Compile but not part of 'make run_tests'
 TEST_GEN_PROGS_EXTENDED = test_sock_addr test_skb_cgroup_id_user \
 	flow_dissector_load test_flow_dissector test_tcp_check_syncookie_user \
-	test_lirc_mode2_user xdping
+	test_lirc_mode2_user xdping test_cpp
 
 TEST_CUSTOM_PROGS = urandom_read
 
@@ -317,6 +317,10 @@ verifier/tests.h: verifier/*.c
 $(OUTPUT)/test_verifier: test_verifier.c verifier/tests.h $(BPFOBJ) | $(OUTPUT)
 	$(CC) $(CFLAGS) $(filter %.a %.o %.c,$^) $(LDLIBS) -o $@
 
+# Make sure we are able to include and link libbpf against c++.
+$(OUTPUT)/test_cpp: test_cpp.cpp $(BPFOBJ)
+	$(CXX) $(CFLAGS) $^ $(LDLIBS) -o $@
+
 EXTRA_CLEAN := $(TEST_CUSTOM_PROGS)					\
 	prog_tests/tests.h map_tests/tests.h verifier/tests.h		\
 	feature $(OUTPUT)/*.o $(OUTPUT)/no_alu32 $(OUTPUT)/bpf_gcc

tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c

@@ -2,25 +2,21 @@
 /* Copyright (c) 2019 Facebook */
 #include <test_progs.h>
 
-#define PROG_CNT 3
-
-void test_fexit_bpf2bpf(void)
+static void test_fexit_bpf2bpf_common(const char *obj_file,
+				      const char *target_obj_file,
+				      int prog_cnt,
+				      const char **prog_name)
 {
-	const char *prog_name[PROG_CNT] = {
-		"fexit/test_pkt_access",
-		"fexit/test_pkt_access_subprog1",
-		"fexit/test_pkt_access_subprog2",
-	};
 	struct bpf_object *obj = NULL, *pkt_obj;
 	int err, pkt_fd, i;
-	struct bpf_link *link[PROG_CNT] = {};
-	struct bpf_program *prog[PROG_CNT];
+	struct bpf_link **link = NULL;
+	struct bpf_program **prog = NULL;
 	__u32 duration, retval;
 	struct bpf_map *data_map;
 	const int zero = 0;
-	u64 result[PROG_CNT];
+	u64 *result = NULL;
 
-	err = bpf_prog_load("./test_pkt_access.o", BPF_PROG_TYPE_UNSPEC,
+	err = bpf_prog_load(target_obj_file, BPF_PROG_TYPE_UNSPEC,
 			    &pkt_obj, &pkt_fd);
 	if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
 		return;
@@ -28,7 +24,14 @@ void test_fexit_bpf2bpf(void)
 			    .attach_prog_fd = pkt_fd,
 			   );
 
-	obj = bpf_object__open_file("./fexit_bpf2bpf.o", &opts);
+	link = calloc(sizeof(struct bpf_link *), prog_cnt);
+	prog = calloc(sizeof(struct bpf_program *), prog_cnt);
+	result = malloc(prog_cnt * sizeof(u64));
+	if (CHECK(!link || !prog || !result, "alloc_memory",
+		  "failed to alloc memory"))
+		goto close_prog;
+
+	obj = bpf_object__open_file(obj_file, &opts);
 	if (CHECK(IS_ERR_OR_NULL(obj), "obj_open",
 		  "failed to open fexit_bpf2bpf: %ld\n",
 		  PTR_ERR(obj)))
@@ -38,7 +41,7 @@ void test_fexit_bpf2bpf(void)
 	if (CHECK(err, "obj_load", "err %d\n", err))
 		goto close_prog;
 
-	for (i = 0; i < PROG_CNT; i++) {
+	for (i = 0; i < prog_cnt; i++) {
 		prog[i] = bpf_object__find_program_by_title(obj, prog_name[i]);
 		if (CHECK(!prog[i], "find_prog", "prog %s not found\n", prog_name[i]))
 			goto close_prog;
@@ -56,21 +59,54 @@ void test_fexit_bpf2bpf(void)
 	      "err %d errno %d retval %d duration %d\n",
 	      err, errno, retval, duration);
 
-	err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, &result);
+	err = bpf_map_lookup_elem(bpf_map__fd(data_map), &zero, result);
 	if (CHECK(err, "get_result",
 		  "failed to get output data: %d\n", err))
 		goto close_prog;
 
-	for (i = 0; i < PROG_CNT; i++)
+	for (i = 0; i < prog_cnt; i++)
 		if (CHECK(result[i] != 1, "result", "fexit_bpf2bpf failed err %ld\n",
 			  result[i]))
 			goto close_prog;
 
 close_prog:
-	for (i = 0; i < PROG_CNT; i++)
+	for (i = 0; i < prog_cnt; i++)
 		if (!IS_ERR_OR_NULL(link[i]))
 			bpf_link__destroy(link[i]);
 	if (!IS_ERR_OR_NULL(obj))
 		bpf_object__close(obj);
 	bpf_object__close(pkt_obj);
+	free(link);
+	free(prog);
+	free(result);
+}
+
+static void test_target_no_callees(void)
+{
+	const char *prog_name[] = {
+		"fexit/test_pkt_md_access",
+	};
+	test_fexit_bpf2bpf_common("./fexit_bpf2bpf_simple.o",
+				  "./test_pkt_md_access.o",
+				  ARRAY_SIZE(prog_name),
+				  prog_name);
+}
+
+static void test_target_yes_callees(void)
+{
+	const char *prog_name[] = {
+		"fexit/test_pkt_access",
+		"fexit/test_pkt_access_subprog1",
+		"fexit/test_pkt_access_subprog2",
+	};
+	test_fexit_bpf2bpf_common("./fexit_bpf2bpf.o",
+				  "./test_pkt_access.o",
+				  ARRAY_SIZE(prog_name),
+				  prog_name);
+}
+
+void test_fexit_bpf2bpf(void)
+{
+	test_target_no_callees();
+	test_target_yes_callees();
 }

tools/testing/selftests/bpf/progs/fexit_bpf2bpf_simple.c

@@ -0,0 +1,26 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2019 Facebook */
+#include <linux/bpf.h>
+#include "bpf_helpers.h"
+#include "bpf_trace_helpers.h"
+
+struct sk_buff {
+	unsigned int len;
+};
+
+__u64 test_result = 0;
+BPF_TRACE_2("fexit/test_pkt_md_access", test_main2,
+	    struct sk_buff *, skb, int, ret)
+{
+	int len;
+
+	__builtin_preserve_access_index(({
+		len = skb->len;
+	}));
+	if (len != 74 || ret != 0)
+		return 0;
+
+	test_result = 1;
+	return 0;
+}
+char _license[] SEC("license") = "GPL";

tools/testing/selftests/bpf/progs/test_pkt_md_access.c

@@ -27,8 +27,8 @@ int _version SEC("version") = 1;
 	}
 #endif
 
-SEC("test1")
-int process(struct __sk_buff *skb)
+SEC("classifier/test_pkt_md_access")
+int test_pkt_md_access(struct __sk_buff *skb)
 {
 	TEST_FIELD(__u8,  len, 0xFF);
 	TEST_FIELD(__u16, len, 0xFFFF);

tools/testing/selftests/bpf/progs/test_tcpbpf_kern.c

@@ -131,6 +131,7 @@ int bpf_testcb(struct bpf_sock_ops *skops)
 				g.bytes_received = skops->bytes_received;
 				g.bytes_acked = skops->bytes_acked;
 			}
+			g.num_close_events++;
 			bpf_map_update_elem(&global_map, &key, &g,
 					    BPF_ANY);
 		}

tools/testing/selftests/bpf/test_skb_cgroup_id_user.c

@@ -120,7 +120,7 @@ int check_ancestor_cgroup_ids(int prog_id)
 	int err = 0;
 	int map_fd;
 
-	expected_ids[0] = 0x100000001;	/* root cgroup */
+	expected_ids[0] = get_cgroup_id("/..");	/* root cgroup */
 	expected_ids[1] = get_cgroup_id("");
 	expected_ids[2] = get_cgroup_id(CGROUP_PATH);
 	expected_ids[3] = 0; /* non-existent cgroup */

tools/testing/selftests/bpf/test_tcpbpf.h

@@ -13,5 +13,6 @@ struct tcpbpf_globals {
 	__u64 bytes_received;
 	__u64 bytes_acked;
 	__u32 num_listen;
+	__u32 num_close_events;
 };
 #endif

tools/testing/selftests/bpf/test_tcpbpf_user.c

@@ -16,6 +16,9 @@
 
 #include "test_tcpbpf.h"
 
+/* 3 comes from one listening socket + both ends of the connection */
+#define EXPECTED_CLOSE_EVENTS		3
+
 #define EXPECT_EQ(expected, actual, fmt)			\
 	do {							\
 		if ((expected) != (actual)) {			\
@@ -23,13 +26,14 @@
 			       "    Actual: %" fmt "\n"		\
 			       "  Expected: %" fmt "\n",	\
 			       (actual), (expected));		\
-			goto err;				\
+			ret--;					\
 		}						\
 	} while (0)
 
 int verify_result(const struct tcpbpf_globals *result)
 {
 	__u32 expected_events;
+	int ret = 0;
 
 	expected_events = ((1 << BPF_SOCK_OPS_TIMEOUT_INIT) |
 			   (1 << BPF_SOCK_OPS_RWND_INIT) |
@@ -48,15 +52,15 @@ int verify_result(const struct tcpbpf_globals *result)
 	EXPECT_EQ(0x80, result->bad_cb_test_rv, PRIu32);
 	EXPECT_EQ(0, result->good_cb_test_rv, PRIu32);
 	EXPECT_EQ(1, result->num_listen, PRIu32);
+	EXPECT_EQ(EXPECTED_CLOSE_EVENTS, result->num_close_events, PRIu32);
 
-	return 0;
-err:
-	return -1;
+	return ret;
 }
 
 int verify_sockopt_result(int sock_map_fd)
 {
 	__u32 key = 0;
+	int ret = 0;
 	int res;
 	int rv;
 
@@ -69,9 +73,7 @@ int verify_sockopt_result(int sock_map_fd)
 	rv = bpf_map_lookup_elem(sock_map_fd, &key, &res);
 	EXPECT_EQ(0, rv, "d");
 	EXPECT_EQ(1, res, "d");
-	return 0;
-err:
-	return -1;
+	return ret;
 }
 
 static int bpf_find_map(const char *test, struct bpf_object *obj,
@@ -96,6 +98,7 @@ int main(int argc, char **argv)
 	int error = EXIT_FAILURE;
 	struct bpf_object *obj;
 	int cg_fd = -1;
+	int retry = 10;
 	__u32 key = 0;
 	int rv;
 
@@ -134,12 +137,20 @@ int main(int argc, char **argv)
 	if (sock_map_fd < 0)
 		goto err;
 
+retry_lookup:
 	rv = bpf_map_lookup_elem(map_fd, &key, &g);
 	if (rv != 0) {
 		printf("FAILED: bpf_map_lookup_elem returns %d\n", rv);
 		goto err;
 	}
 
+	if (g.num_close_events != EXPECTED_CLOSE_EVENTS && retry--) {
+		printf("Unexpected number of close events (%d), retrying!\n",
+		       g.num_close_events);
+		usleep(100);
+		goto retry_lookup;
+	}
+
 	if (verify_result(&g)) {
 		printf("FAILED: Wrong stats\n");
 		goto err;