From: Joe Stringer <joe@xxxxxxxxxxx>
Add tests for libbpf relocation of static variable references
into the .data, .rodata and .bss sections of the ELF. Tests with
different offsets are all passing:
# ./test_progs
[...]
test_static_data_access:PASS:load program 0 nsec
test_static_data_access:PASS:pass packet 278 nsec
test_static_data_access:PASS:relocate .bss reference 1 278 nsec
test_static_data_access:PASS:relocate .data reference 1 278 nsec
test_static_data_access:PASS:relocate .rodata reference 1 278 nsec
test_static_data_access:PASS:relocate .bss reference 2 278 nsec
test_static_data_access:PASS:relocate .data reference 2 278 nsec
test_static_data_access:PASS:relocate .rodata reference 2 278 nsec
test_static_data_access:PASS:relocate .bss reference 3 278 nsec
test_static_data_access:PASS:relocate .bss reference 4 278 nsec
Summary: 223 PASSED, 0 FAILED
Joint work with Daniel Borkmann.
Signed-off-by: Joe Stringer <joe@xxxxxxxxxxx>
Signed-off-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
---
tools/testing/selftests/bpf/bpf_helpers.h | 2 +-
.../selftests/bpf/progs/test_global_data.c | 61 +++++++++++++++++++
tools/testing/selftests/bpf/test_progs.c | 50 +++++++++++++++
3 files changed, 112 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/test_global_data.c
diff --git a/tools/testing/selftests/bpf/bpf_helpers.h b/tools/testing/selftests/bpf/bpf_helpers.h
index d9999f1ed1d2..0463662935f9 100644
--- a/tools/testing/selftests/bpf/bpf_helpers.h
+++ b/tools/testing/selftests/bpf/bpf_helpers.h
@@ -11,7 +11,7 @@
/* helper functions called from eBPF programs written in C */
static void *(*bpf_map_lookup_elem)(void *map, void *key) =
(void *) BPF_FUNC_map_lookup_elem;
-static int (*bpf_map_update_elem)(void *map, void *key, void *value,
+static int (*bpf_map_update_elem)(void *map, const void *key, const void *value,
unsigned long long flags) =
(void *) BPF_FUNC_map_update_elem;
static int (*bpf_map_delete_elem)(void *map, void *key) =
diff --git a/tools/testing/selftests/bpf/progs/test_global_data.c b/tools/testing/selftests/bpf/progs/test_global_data.c
new file mode 100644
index 000000000000..2a7cf40b8efb
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_global_data.c
@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2019 Isovalent, Inc.
+
+#include <linux/bpf.h>
+#include <linux/pkt_cls.h>
+#include <string.h>
+
+#include "bpf_helpers.h"
+
+struct bpf_map_def SEC("maps") result = {
+ .type = BPF_MAP_TYPE_ARRAY,
+ .key_size = sizeof(__u32),
+ .value_size = sizeof(__u64),
+ .max_entries = 9,
+};
+
+static __u64 static_bss = 0; /* Reloc reference to .bss section */
+static __u64 static_data = 42; /* Reloc reference to .data section */
+static const __u64 static_rodata = 24; /* Reloc reference to .rodata section */
+static __u64 static_bss2 = 0; /* Reloc reference to .bss section */
+static __u64 static_data2 = 0xffeeff; /* Reloc reference to .data section */
+static const __u64 static_rodata2 = 0xabab; /* Reloc reference to .rodata section */
+static const __u64 static_rodata3 = 0xab; /* Reloc reference to .rodata section */
+
+SEC("static_data_load")
+int load_static_data(struct __sk_buff *skb)
+{
+ __u32 key;
+
+ key = 0;
+ bpf_map_update_elem(&result, &key, &static_bss, 0);
+
+ key = 1;
+ bpf_map_update_elem(&result, &key, &static_data, 0);
+
+ key = 2;
+ bpf_map_update_elem(&result, &key, &static_rodata, 0);
+
+ key = 3;
+ bpf_map_update_elem(&result, &key, &static_bss2, 0);
+
+ key = 4;
+ bpf_map_update_elem(&result, &key, &static_data2, 0);
+
+ key = 5;
+ bpf_map_update_elem(&result, &key, &static_rodata2, 0);
+
+ key = 6;
+ static_bss2 = 1234;
+ bpf_map_update_elem(&result, &key, &static_bss2, 0);
+
+ key = 7;
+ bpf_map_update_elem(&result, &key, &static_bss, 0);
+
+ key = 8;
+ bpf_map_update_elem(&result, &key, &static_rodata3, 0);
+
+ return TC_ACT_OK;
+}
+
+char _license[] SEC("license") = "GPL";
diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
index c59d2e015d16..a3e64c054572 100644
--- a/tools/testing/selftests/bpf/test_progs.c
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -738,6 +738,55 @@ static void test_pkt_md_access(void)
bpf_object__close(obj);
}
+static void test_static_data_access(void)
+{
+ const char *file = "./test_global_data.o";
+ struct bpf_object *obj;
+ __u32 duration = 0, retval;
+ int i, err, prog_fd, map_fd;
+ uint64_t value;
+
+ err = bpf_prog_load(file, BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd);
+ if (CHECK(err, "load program", "error %d loading %s\n", err, file))
+ return;
+
+ map_fd = bpf_find_map(__func__, obj, "result");
+ if (map_fd < 0) {
+ error_cnt++;
+ goto close_prog;
+ }
+
+ err = bpf_prog_test_run(prog_fd, 1, &pkt_v4, sizeof(pkt_v4),
+ NULL, NULL, &retval, &duration);
+ CHECK(err || retval, "pass packet",
+ "err %d errno %d retval %d duration %d\n",
+ err, errno, retval, duration);
+
+ struct {
+ char *name;
+ uint32_t key;
+ uint64_t value;
+ } tests[] = {
+ { "relocate .bss reference 1", 0, 0 },
+ { "relocate .data reference 1", 1, 42 },
+ { "relocate .rodata reference 1", 2, 24 },
+ { "relocate .bss reference 2", 3, 0 },
+ { "relocate .data reference 2", 4, 0xffeeff },
+ { "relocate .rodata reference 2", 5, 0xabab },
+ { "relocate .bss reference 3", 6, 1234 },
+ { "relocate .bss reference 4", 7, 0 },
+ };
+ for (i = 0; i < sizeof(tests) / sizeof(tests[0]); i++) {
+ err = bpf_map_lookup_elem(map_fd, &tests[i].key, &value);
+ CHECK (err || value != tests[i].value, tests[i].name,
+ "err %d result %lu expected %lu\n",
+ err, value, tests[i].value);
+ }
+
+close_prog:
+ bpf_object__close(obj);
+}
+
static void test_obj_name(void)
{
struct {
@@ -2182,6 +2231,7 @@ int main(void)
test_map_lock();
test_signal_pending(BPF_PROG_TYPE_SOCKET_FILTER);
test_signal_pending(BPF_PROG_TYPE_FLOW_DISSECTOR);
+ test_static_data_access();
printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
return error_cnt ? EXIT_FAILURE : EXIT_SUCCESS;
--
2.17.1
