[PATCH bpf-next v3 7/7] selftests/bpf: add test cases for queue and stack maps

Mauricio Vasquez B
2018-10-18T21:18:05Z

test_maps:
Tests that queue/stack maps are behaving correctly even in corner cases

test_progs:
Tests new ebpf helpers

Signed-off-by: Mauricio Vasquez B <mauricio.vasquez@polito.it>
---
tools/lib/bpf/bpf.c | 12 ++
tools/lib/bpf/bpf.h | 2
tools/testing/selftests/bpf/Makefile | 5 +
tools/testing/selftests/bpf/bpf_helpers.h | 7 +
tools/testing/selftests/bpf/test_maps.c | 122 ++++++++++++++++++++
tools/testing/selftests/bpf/test_progs.c | 99 ++++++++++++++++
tools/testing/selftests/bpf/test_queue_map.c | 4 +
tools/testing/selftests/bpf/test_queue_stack_map.h | 59 ++++++++++
tools/testing/selftests/bpf/test_stack_map.c | 4 +
9 files changed, 313 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/test_queue_map.c
create mode 100644 tools/testing/selftests/bpf/test_queue_stack_map.h
create mode 100644 tools/testing/selftests/bpf/test_stack_map.c

diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index d70a255cb05e..03f9bcc4ef50 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -278,6 +278,18 @@ int bpf_map_lookup_elem(int fd, const void *key, void *value)
return sys_bpf(BPF_MAP_LOOKUP_ELEM, &attr, sizeof(attr));
}

+int bpf_map_lookup_and_delete_elem(int fd, const void *key, void *value)
+{
+ union bpf_attr attr;
+
+ bzero(&attr, sizeof(attr));
+ attr.map_fd = fd;
+ attr.key = ptr_to_u64(key);
+ attr.value = ptr_to_u64(value);
+
+ return sys_bpf(BPF_MAP_LOOKUP_AND_DELETE_ELEM, &attr, sizeof(attr));
+}
+
int bpf_map_delete_elem(int fd, const void *key)
{
union bpf_attr attr;
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 258c3c178333..26a51538213c 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -99,6 +99,8 @@ LIBBPF_API int bpf_map_update_elem(int fd, const void *key, const void *value,
__u64 flags);

LIBBPF_API int bpf_map_lookup_elem(int fd, const void *key, void *value);
+LIBBPF_API int bpf_map_lookup_and_delete_elem(int fd, const void *key,
+ void *value);
LIBBPF_API int bpf_map_delete_elem(int fd, const void *key);
LIBBPF_API int bpf_map_get_next_key(int fd, const void *key, void *next_key);
LIBBPF_API int bpf_obj_pin(int fd, const char *pathname);
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index d99dd6fc3fbe..e39dfb4e7970 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -37,7 +37,7 @@ TEST_GEN_FILES = test_pkt_access.o test_xdp.o test_l4lb.o test_tcp_estats.o test
test_lwt_seg6local.o sendmsg4_prog.o sendmsg6_prog.o test_lirc_mode2_kern.o \
get_cgroup_id_kern.o socket_cookie_prog.o test_select_reuseport_kern.o \
test_skb_cgroup_id_kern.o bpf_flow.o netcnt_prog.o \
- test_sk_lookup_kern.o test_xdp_vlan.o
+ test_sk_lookup_kern.o test_xdp_vlan.o test_queue_map.o test_stack_map.o

# Order correspond to 'make run_tests' order
TEST_PROGS := test_kmod.sh \
@@ -118,6 +118,9 @@ CLANG_FLAGS = -I. -I./include/uapi -I../../../include/uapi \
$(OUTPUT)/test_l4lb_noinline.o: CLANG_FLAGS += -fno-inline
$(OUTPUT)/test_xdp_noinline.o: CLANG_FLAGS += -fno-inline

+$(OUTPUT)/test_queue_map.o: test_queue_stack_map.h
+$(OUTPUT)/test_stack_map.o: test_queue_stack_map.h
+
BTF_LLC_PROBE := $(shell $(LLC) -march=bpf -mattr=help 2>&1 | grep dwarfris)
BTF_PAHOLE_PROBE := $(shell $(BTF_PAHOLE) --help 2>&1 | grep BTF)
BTF_OBJCOPY_PROBE := $(shell $(LLVM_OBJCOPY) --help 2>&1 | grep -i 'usage.*llvm')
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index fda8c162d0df..6407a3df0f3b 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -16,6 +16,13 @@ static int (*bpf_map_update_elem)(void *map, void *key, void *value,
(void *) BPF_FUNC_map_update_elem;
static int (*bpf_map_delete_elem)(void *map, void *key) =
(void *) BPF_FUNC_map_delete_elem;
+static int (*bpf_map_push_elem)(void *map, void *value,
+ unsigned long long flags) =
+ (void *) BPF_FUNC_map_push_elem;
+static int (*bpf_map_pop_elem)(void *map, void *value) =
+ (void *) BPF_FUNC_map_pop_elem;
+static int (*bpf_map_peek_elem)(void *map, void *value) =
+ (void *) BPF_FUNC_map_peek_elem;
static int (*bpf_probe_read)(void *dst, int size, void *unsafe_ptr) =
(void *) BPF_FUNC_probe_read;
static unsigned long long (*bpf_ktime_get_ns)(void) =
diff --git a/tools/testing/selftests/bpf/test_maps.c b/tools/testing/selftests/bpf/test_maps.c
index 9b552c0fc47d..4db2116e52be 100644
--- a/tools/testing/selftests/bpf/test_maps.c
+++ b/tools/testing/selftests/bpf/test_maps.c
@@ -15,6 +15,7 @@
#include <string.h>
#include <assert.h>
#include <stdlib.h>
+#include <time.h>

#include <sys/wait.h>
#include <sys/socket.h>
@@ -471,6 +472,122 @@ static void test_devmap(int task, void *data)
close(fd);
}

+static void test_queuemap(int task, void *data)
+{
+ const int MAP_SIZE = 32;
+ __u32 vals[MAP_SIZE + MAP_SIZE/2], val;
+ int fd, i;
+
+ /* Fill test values to be used */
+ for (i = 0; i < MAP_SIZE + MAP_SIZE/2; i++)
+ vals[i] = rand();
+
+ /* Invalid key size */
+ fd = bpf_create_map(BPF_MAP_TYPE_QUEUE, 4, sizeof(val), MAP_SIZE,
+ map_flags);
+ assert(fd < 0 && errno == EINVAL);
+
+ fd = bpf_create_map(BPF_MAP_TYPE_QUEUE, 0, sizeof(val), MAP_SIZE,
+ map_flags);
+ /* Queue map does not support BPF_F_NO_PREALLOC */
+ if (map_flags & BPF_F_NO_PREALLOC) {
+ assert(fd < 0 && errno == EINVAL);
+ return;
+ }
+ if (fd < 0) {
+ printf("Failed to create queuemap '%s'!\n", strerror(errno));
+ exit(1);
+ }
+
+ /* Push MAP_SIZE elements */
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_map_update_elem(fd, NULL, &vals[i], 0) == 0);
+
+ /* Check that element cannot be pushed due to max_entries limit */
+ assert(bpf_map_update_elem(fd, NULL, &val, 0) == -1 &&
+ errno == E2BIG);
+
+ /* Peek element */
+ assert(bpf_map_lookup_elem(fd, NULL, &val) == 0 && val == vals[0]);
+
+ /* Replace half elements */
+ for (i = MAP_SIZE; i < MAP_SIZE + MAP_SIZE/2; i++)
+ assert(bpf_map_update_elem(fd, NULL, &vals[i], BPF_EXIST) == 0);
+
+ /* Pop all elements */
+ for (i = MAP_SIZE/2; i < MAP_SIZE + MAP_SIZE/2; i++)
+ assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == 0 &&
+ val == vals[i]);
+
+ /* Check that there are not elements left */
+ assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == -1 &&
+ errno == ENOENT);
+
+ /* Check that non supported functions set errno to EINVAL */
+ assert(bpf_map_delete_elem(fd, NULL) == -1 && errno == EINVAL);
+ assert(bpf_map_get_next_key(fd, NULL, NULL) == -1 && errno == EINVAL);
+
+ close(fd);
+}
+
+static void test_stackmap(int task, void *data)
+{
+ const int MAP_SIZE = 32;
+ __u32 vals[MAP_SIZE + MAP_SIZE/2], val;
+ int fd, i;
+
+ /* Fill test values to be used */
+ for (i = 0; i < MAP_SIZE + MAP_SIZE/2; i++)
+ vals[i] = rand();
+
+ /* Invalid key size */
+ fd = bpf_create_map(BPF_MAP_TYPE_STACK, 4, sizeof(val), MAP_SIZE,
+ map_flags);
+ assert(fd < 0 && errno == EINVAL);
+
+ fd = bpf_create_map(BPF_MAP_TYPE_STACK, 0, sizeof(val), MAP_SIZE,
+ map_flags);
+ /* Stack map does not support BPF_F_NO_PREALLOC */
+ if (map_flags & BPF_F_NO_PREALLOC) {
+ assert(fd < 0 && errno == EINVAL);
+ return;
+ }
+ if (fd < 0) {
+ printf("Failed to create stackmap '%s'!\n", strerror(errno));
+ exit(1);
+ }
+
+ /* Push MAP_SIZE elements */
+ for (i = 0; i < MAP_SIZE; i++)
+ assert(bpf_map_update_elem(fd, NULL, &vals[i], 0) == 0);
+
+ /* Check that element cannot be pushed due to max_entries limit */
+ assert(bpf_map_update_elem(fd, NULL, &val, 0) == -1 &&
+ errno == E2BIG);
+
+ /* Peek element */
+ assert(bpf_map_lookup_elem(fd, NULL, &val) == 0 && val == vals[i - 1]);
+
+ /* Replace half elements */
+ for (i = MAP_SIZE; i < MAP_SIZE + MAP_SIZE/2; i++)
+ assert(bpf_map_update_elem(fd, NULL, &vals[i], BPF_EXIST) == 0);
+
+ /* Pop all elements */
+ for (i = MAP_SIZE + MAP_SIZE/2 - 1; i >= MAP_SIZE/2; i--)
+ assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == 0 &&
+ val == vals[i]);
+
+ /* Check that there are not elements left */
+ assert(bpf_map_lookup_and_delete_elem(fd, NULL, &val) == -1 &&
+ errno == ENOENT);
+
+ /* Check that non supported functions set errno to EINVAL */
+ assert(bpf_map_delete_elem(fd, NULL) == -1 && errno == EINVAL);
+ assert(bpf_map_get_next_key(fd, NULL, NULL) == -1 && errno == EINVAL);
+
+ close(fd);
+}
+
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <arpa/inet.h>
@@ -1434,10 +1551,15 @@ static void run_all_tests(void)
test_map_wronly();

test_reuseport_array();
+
+ test_queuemap(0, NULL);
+ test_stackmap(0, NULL);
}

int main(void)
{
+ srand(time(NULL));
+
map_flags = 0;
run_all_tests();

diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index e8becca9c521..2d3c04f45530 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -1735,8 +1735,105 @@ static void test_reference_tracking()
bpf_object__close(obj);
}

+enum {
+ QUEUE,
+ STACK,
+};
+
+static void test_queue_stack_map(int type)
+{
+ const int MAP_SIZE = 32;
+ __u32 vals[MAP_SIZE], duration, retval, size, val;
+ int i, err, prog_fd, map_in_fd, map_out_fd;
+ char file[32], buf[128];
+ struct bpf_object *obj;
+ struct iphdr *iph = (void *)buf + sizeof(struct ethhdr);
+
+ /* Fill test values to be used */
+ for (i = 0; i < MAP_SIZE; i++)
+ vals[i] = rand();
+
+ if (type == QUEUE)
+ strncpy(file, "./test_queue_map.o", sizeof(file));
+ else if (type == STACK)
+ strncpy(file, "./test_stack_map.o", sizeof(file));
+ else
+ return;
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd);
+ if (err) {
+ error_cnt++;
+ return;
+ }
+
+ map_in_fd = bpf_find_map(__func__, obj, "map_in");
+ if (map_in_fd < 0)
+ goto out;
+
+ map_out_fd = bpf_find_map(__func__, obj, "map_out");
+ if (map_out_fd < 0)
+ goto out;
+
+ /* Push 32 elements to the input map */
+ for (i = 0; i < MAP_SIZE; i++) {
+ err = bpf_map_update_elem(map_in_fd, NULL, &vals[i], 0);
+ if (err) {
+ error_cnt++;
+ goto out;
+ }
+ }
+
+ /* The eBPF program pushes iph.saddr in the output map,
+ * pops the input map and saves this value in iph.daddr
+ */
+ for (i = 0; i < MAP_SIZE; i++) {
+ if (type == QUEUE) {
+ val = vals[i];
+ pkt_v4.iph.saddr = vals[i] * 5;
+ } else if (type == STACK) {
+ val = vals[MAP_SIZE - 1 - i];
+ pkt_v4.iph.saddr = vals[MAP_SIZE - 1 - i] * 5;
+ }
+
+ err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
+ buf, &size, &retval, &duration);
+ if (err || retval || size != sizeof(pkt_v4) ||
+ iph->daddr != val)
+ break;
+ }
+
+ CHECK(err || retval || size != sizeof(pkt_v4) || iph->daddr != val,
+ "bpf_map_pop_elem",
+ "err %d errno %d retval %d size %d iph->daddr %u\n",
+ err, errno, retval, size, iph->daddr);
+
+ /* Queue is empty, program should return TC_ACT_SHOT */
+ err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
+ buf, &size, &retval, &duration);
+ CHECK(err || retval != 2 /* TC_ACT_SHOT */|| size != sizeof(pkt_v4),
+ "check-queue-stack-map-empty",
+ "err %d errno %d retval %d size %d\n",
+ err, errno, retval, size);
+
+ /* Check that the program pushed elements correctly */
+ for (i = 0; i < MAP_SIZE; i++) {
+ err = bpf_map_lookup_and_delete_elem(map_out_fd, NULL, &val);
+ if (err || val != vals[i] * 5)
+ break;
+ }
+
+ CHECK(i != MAP_SIZE && (err || val != vals[i] * 5),
+ "bpf_map_push_elem", "err %d value %u\n", err, val);
+
+out:
+ pkt_v4.iph.saddr = 0;
+ bpf_object__close(obj);
+}
+
int main(void)
{
+ srand(time(NULL));
+
jit_enabled = is_jit_enabled();

test_pkt_access();
@@ -1757,6 +1854,8 @@ int main(void)
test_task_fd_query_rawtp();
test_task_fd_query_tp();
test_reference_tracking();
+ test_queue_stack_map(QUEUE);
+ test_queue_stack_map(STACK);

printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
diff --git a/tools/testing/selftests/bpf/test_queue_map.c b/tools/testing/selftests/bpf/test_queue_map.c
new file mode 100644
index 000000000000..87db1f9da33d
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_queue_map.c
@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Politecnico di Torino
+#define MAP_TYPE BPF_MAP_TYPE_QUEUE
+#include "test_queue_stack_map.h"
diff --git a/tools/testing/selftests/bpf/test_queue_stack_map.h b/tools/testing/selftests/bpf/test_queue_stack_map.h
new file mode 100644
index 000000000000..295b9b3bc5c7
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_queue_stack_map.h
@@ -0,0 +1,59 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+// Copyright (c) 2018 Politecnico di Torino
+#include <stddef.h>
+#include <string.h>
+#include <linux/bpf.h>
+#include <linux/if_ether.h>
+#include <linux/ip.h>
+#include <linux/pkt_cls.h>
+#include "bpf_helpers.h"
+
+int _version SEC("version") = 1;
+
+struct bpf_map_def __attribute__ ((section("maps"), used)) map_in = {
+ .type = MAP_TYPE,
+ .key_size = 0,
+ .value_size = sizeof(__u32),
+ .max_entries = 32,
+ .map_flags = 0,
+};
+
+struct bpf_map_def __attribute__ ((section("maps"), used)) map_out = {
+ .type = MAP_TYPE,
+ .key_size = 0,
+ .value_size = sizeof(__u32),
+ .max_entries = 32,
+ .map_flags = 0,
+};
+
+SEC("test")
+int _test(struct __sk_buff *skb)
+{
+ void *data_end = (void *)(long)skb->data_end;
+ void *data = (void *)(long)skb->data;
+ struct ethhdr *eth = (struct ethhdr *)(data);
+ __u32 value;
+ int err;
+
+ if (eth + 1 > data_end)
+ return TC_ACT_SHOT;
+
+ struct iphdr *iph = (struct iphdr *)(eth + 1);
+
+ if (iph + 1 > data_end)
+ return TC_ACT_SHOT;
+
+ err = bpf_map_pop_elem(&map_in, &value);
+ if (err)
+ return TC_ACT_SHOT;
+
+ iph->daddr = value;
+
+ err = bpf_map_push_elem(&map_out, &iph->saddr, 0);
+ if (err)
+ return TC_ACT_SHOT;
+
+ return TC_ACT_OK;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_stack_map.c b/tools/testing/selftests/bpf/test_stack_map.c
new file mode 100644
index 000000000000..31c3880e6da0
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_stack_map.c
@@ -0,0 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2018 Politecnico di Torino
+#define MAP_TYPE BPF_MAP_TYPE_STACK
+#include "test_queue_stack_map.h"