bpf, selftest: test {rd, wr}only flags and direct value access

Extend test_verifier with various test cases around the two kernel
extensions, that is, {rd,wr}only map support as well as direct map
value access. All passing, one skipped due to xskmap not present
on test machine:

  # ./test_verifier
  [...]
  #948/p XDP pkt read, pkt_meta' <= pkt_data, bad access 1 OK
  #949/p XDP pkt read, pkt_meta' <= pkt_data, bad access 2 OK
  #950/p XDP pkt read, pkt_data <= pkt_meta', good access OK
  #951/p XDP pkt read, pkt_data <= pkt_meta', bad access 1 OK
  #952/p XDP pkt read, pkt_data <= pkt_meta', bad access 2 OK
  Summary: 1410 PASSED, 1 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 47 insertions, 4 deletions

diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 75ef63b42f2c..e2ebcaddbe78 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -52,7 +52,7 @@
 #define MAX_INSNS	BPF_MAXINSNS
 #define MAX_TEST_INSNS	1000000
 #define MAX_FIXUPS	8
-#define MAX_NR_MAPS	14
+#define MAX_NR_MAPS	16
 #define MAX_TEST_RUNS	8
 #define POINTER_VALUE	0xcafe4all
 #define TEST_DATA_LEN	64
@@ -82,6 +82,9 @@ struct bpf_test {
 	int fixup_cgroup_storage[MAX_FIXUPS];
 	int fixup_percpu_cgroup_storage[MAX_FIXUPS];
 	int fixup_map_spin_lock[MAX_FIXUPS];
+	int fixup_map_array_ro[MAX_FIXUPS];
+	int fixup_map_array_wo[MAX_FIXUPS];
+	int fixup_map_array_small[MAX_FIXUPS];
 	const char *errstr;
 	const char *errstr_unpriv;
 	uint32_t retval, retval_unpriv, insn_processed;
@@ -285,13 +288,15 @@ static bool skip_unsupported_map(enum bpf_map_type map_type)
 	return false;
 }
 
-static int create_map(uint32_t type, uint32_t size_key,
-		      uint32_t size_value, uint32_t max_elem)
+static int __create_map(uint32_t type, uint32_t size_key,
+			uint32_t size_value, uint32_t max_elem,
+			uint32_t extra_flags)
 {
 	int fd;
 
 	fd = bpf_create_map(type, size_key, size_value, max_elem,
-			    type == BPF_MAP_TYPE_HASH ? BPF_F_NO_PREALLOC : 0);
+			    (type == BPF_MAP_TYPE_HASH ?
+			     BPF_F_NO_PREALLOC : 0) | extra_flags);
 	if (fd < 0) {
 		if (skip_unsupported_map(type))
 			return -1;
@@ -301,6 +306,12 @@ static int create_map(uint32_t type, uint32_t size_key,
 	return fd;
 }
 
+static int create_map(uint32_t type, uint32_t size_key,
+		      uint32_t size_value, uint32_t max_elem)
+{
+	return __create_map(type, size_key, size_value, max_elem, 0);
+}
+
 static void update_map(int fd, int index)
 {
 	struct test_val value = {
@@ -527,6 +538,9 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
 	int *fixup_cgroup_storage = test->fixup_cgroup_storage;
 	int *fixup_percpu_cgroup_storage = test->fixup_percpu_cgroup_storage;
 	int *fixup_map_spin_lock = test->fixup_map_spin_lock;
+	int *fixup_map_array_ro = test->fixup_map_array_ro;
+	int *fixup_map_array_wo = test->fixup_map_array_wo;
+	int *fixup_map_array_small = test->fixup_map_array_small;
 
 	if (test->fill_helper) {
 		test->fill_insns = calloc(MAX_TEST_INSNS, sizeof(struct bpf_insn));
@@ -652,6 +666,35 @@ static void do_test_fixup(struct bpf_test *test, enum bpf_prog_type prog_type,
 			fixup_map_spin_lock++;
 		} while (*fixup_map_spin_lock);
 	}
+	if (*fixup_map_array_ro) {
+		map_fds[14] = __create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
+					   sizeof(struct test_val), 1,
+					   BPF_F_RDONLY_PROG);
+		update_map(map_fds[14], 0);
+		do {
+			prog[*fixup_map_array_ro].imm = map_fds[14];
+			fixup_map_array_ro++;
+		} while (*fixup_map_array_ro);
+	}
+	if (*fixup_map_array_wo) {
+		map_fds[15] = __create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
+					   sizeof(struct test_val), 1,
+					   BPF_F_WRONLY_PROG);
+		update_map(map_fds[15], 0);
+		do {
+			prog[*fixup_map_array_wo].imm = map_fds[15];
+			fixup_map_array_wo++;
+		} while (*fixup_map_array_wo);
+	}
+	if (*fixup_map_array_small) {
+		map_fds[16] = __create_map(BPF_MAP_TYPE_ARRAY, sizeof(int),
+					   1, 1, 0);
+		update_map(map_fds[16], 0);
+		do {
+			prog[*fixup_map_array_small].imm = map_fds[16];
+			fixup_map_array_small++;
+		} while (*fixup_map_array_small);
+	}
 }
 
 static int set_admin(bool admin)