From: Chenbo Feng <fengc@google.com>
Date: Wed, 18 Oct 2017 13:00:23 -0700
Subject: bpf: Add tests for eBPF file mode
Patch-mainline: v4.15-rc1
Git-commit: e043325b308745d6968673e7b53080bd7cc39f08
References: bsc#1109837

Two related tests are added into bpf selftest to test read only map and
write only map. The tests verified the read only and write only flags
are working on hash maps.

Signed-off-by: Chenbo Feng <fengc@google.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Acked-by: Thomas Bogendoerfer <tbogendoerfer@suse.de>
---
 tools/testing/selftests/bpf/test_maps.c |   48 ++++++++++++++++++++++++++++++++
 1 file changed, 48 insertions(+)

--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -1043,6 +1043,51 @@ static void test_map_parallel(void)
 	assert(bpf_map_get_next_key(fd, &key, &key) == -1 && errno == ENOENT);
 }
 
+static void test_map_rdonly(void)
+{
+	int i, fd, key = 0, value = 0;
+
+	fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+			    MAP_SIZE, map_flags | BPF_F_RDONLY);
+	if (fd < 0) {
+		printf("Failed to create map for read only test '%s'!\n",
+		       strerror(errno));
+		exit(1);
+	}
+
+	key = 1;
+	value = 1234;
+	/* Insert key=1 element. */
+	assert(bpf_map_update_elem(fd, &key, &value, BPF_ANY) == -1 &&
+	       errno == EPERM);
+
+	/* Check that key=2 is not found. */
+	assert(bpf_map_lookup_elem(fd, &key, &value) == -1 && errno == ENOENT);
+	assert(bpf_map_get_next_key(fd, &key, &value) == -1 && errno == ENOENT);
+}
+
+static void test_map_wronly(void)
+{
+	int i, fd, key = 0, value = 0;
+
+	fd = bpf_create_map(BPF_MAP_TYPE_HASH, sizeof(key), sizeof(value),
+			    MAP_SIZE, map_flags | BPF_F_WRONLY);
+	if (fd < 0) {
+		printf("Failed to create map for read only test '%s'!\n",
+		       strerror(errno));
+		exit(1);
+	}
+
+	key = 1;
+	value = 1234;
+	/* Insert key=1 element. */
+	assert(bpf_map_update_elem(fd, &key, &value, BPF_ANY) == 0)
+
+	/* Check that key=2 is not found. */
+	assert(bpf_map_lookup_elem(fd, &key, &value) == -1 && errno == EPERM);
+	assert(bpf_map_get_next_key(fd, &key, &value) == -1 && errno == EPERM);
+}
+
 static void run_all_tests(void)
 {
 	test_hashmap(0, NULL);
@@ -1060,6 +1105,9 @@ static void run_all_tests(void)
 	test_map_large();
 	test_map_parallel();
 	test_map_stress();
+
+	test_map_rdonly();
+	test_map_wronly();
 }
 
 int main(void)