selftests/bpf: Introduce veristat test

Introducing test for veristat, part of test_progs.
Test cases cover functionality of setting global variables in BPF
program.

Signed-off-by: Mykyta Yatsenko <yatsenko@meta.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20250225163101.121043-3-mykyta.yatsenko5@gmail.com

4 files changed, 195 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 5dc9c84ed30f..abfb450c26bb 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -688,6 +688,7 @@ $(OUTPUT)/$(TRUNNER_BINARY): $(TRUNNER_TEST_OBJS)			\
 			     $(TRUNNER_EXTRA_OBJS) $$(BPFOBJ)		\
 			     $(RESOLVE_BTFIDS)				\
 			     $(TRUNNER_BPFTOOL)				\
+			     $(OUTPUT)/veristat				\
 			     | $(TRUNNER_BINARY)-extras
 	$$(call msg,BINARY,,$$@)
 	$(Q)$$(CC) $$(CFLAGS) $$(filter %.a %.o,$$^) $$(LDLIBS) $$(LDFLAGS) -o $$@
diff --git a/tools/testing/selftests/bpf/prog_tests/test_veristat.c b/tools/testing/selftests/bpf/prog_tests/test_veristat.c
new file mode 100644
index 000000000000..a95b42bf744a
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/test_veristat.c
@@ -0,0 +1,139 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
+#include <test_progs.h>
+#include <string.h>
+#include <stdio.h>
+
+#define __CHECK_STR(str, name)					    \
+	do {							    \
+		if (!ASSERT_HAS_SUBSTR(fix->output, (str), (name))) \
+			goto out;				    \
+	} while (0)
+
+struct fixture {
+	char tmpfile[80];
+	int fd;
+	char *output;
+	size_t sz;
+	char veristat[80];
+};
+
+static struct fixture *init_fixture(void)
+{
+	struct fixture *fix = malloc(sizeof(struct fixture));
+
+	/* for no_alu32 and cpuv4 veristat is in parent folder */
+	if (access("./veristat", F_OK) == 0)
+		strcpy(fix->veristat, "./veristat");
+	else if (access("../veristat", F_OK) == 0)
+		strcpy(fix->veristat, "../veristat");
+	else
+		PRINT_FAIL("Can't find veristat binary");
+
+	snprintf(fix->tmpfile, sizeof(fix->tmpfile), "/tmp/test_veristat.XXXXXX");
+	fix->fd = mkstemp(fix->tmpfile);
+	fix->sz = 1000000;
+	fix->output = malloc(fix->sz);
+	return fix;
+}
+
+static void teardown_fixture(struct fixture *fix)
+{
+	free(fix->output);
+	close(fix->fd);
+	remove(fix->tmpfile);
+	free(fix);
+}
+
+static void test_set_global_vars_succeeds(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS(out,
+	    "%s set_global_vars.bpf.o"\
+	    " -G \"var_s64 = 0xf000000000000001\" "\
+	    " -G \"var_u64 = 0xfedcba9876543210\" "\
+	    " -G \"var_s32 = -0x80000000\" "\
+	    " -G \"var_u32 = 0x76543210\" "\
+	    " -G \"var_s16 = -32768\" "\
+	    " -G \"var_u16 = 60652\" "\
+	    " -G \"var_s8 = -128\" "\
+	    " -G \"var_u8 = 255\" "\
+	    " -G \"var_ea = EA2\" "\
+	    " -G \"var_eb = EB2\" "\
+	    " -G \"var_ec = EC2\" "\
+	    " -G \"var_b = 1\" "\
+	    "-vl2 > %s", fix->veristat, fix->tmpfile);
+
+	read(fix->fd, fix->output, fix->sz);
+	__CHECK_STR("_w=0xf000000000000001 ", "var_s64 = 0xf000000000000001");
+	__CHECK_STR("_w=0xfedcba9876543210 ", "var_u64 = 0xfedcba9876543210");
+	__CHECK_STR("_w=0x80000000 ", "var_s32 = -0x80000000");
+	__CHECK_STR("_w=0x76543210 ", "var_u32 = 0x76543210");
+	__CHECK_STR("_w=0x8000 ", "var_s16 = -32768");
+	__CHECK_STR("_w=0xecec ", "var_u16 = 60652");
+	__CHECK_STR("_w=128 ", "var_s8 = -128");
+	__CHECK_STR("_w=255 ", "var_u8 = 255");
+	__CHECK_STR("_w=11 ", "var_ea = EA2");
+	__CHECK_STR("_w=12 ", "var_eb = EB2");
+	__CHECK_STR("_w=13 ", "var_ec = EC2");
+	__CHECK_STR("_w=1 ", "var_b = 1");
+
+out:
+	teardown_fixture(fix);
+}
+
+static void test_set_global_vars_from_file_succeeds(void)
+{
+	struct fixture *fix = init_fixture();
+	char input_file[80];
+	const char *vars = "var_s16 = -32768\nvar_u16 = 60652";
+	int fd;
+
+	snprintf(input_file, sizeof(input_file), "/tmp/veristat_input.XXXXXX");
+	fd = mkstemp(input_file);
+	if (!ASSERT_GE(fd, 0, "valid fd"))
+		goto out;
+
+	write(fd, vars, strlen(vars));
+	syncfs(fd);
+	SYS(out, "%s set_global_vars.bpf.o -G \"@%s\" -vl2 > %s",
+	    fix->veristat, input_file, fix->tmpfile);
+	read(fix->fd, fix->output, fix->sz);
+	__CHECK_STR("_w=0x8000 ", "var_s16 = -32768");
+	__CHECK_STR("_w=0xecec ", "var_u16 = 60652");
+
+out:
+	close(fd);
+	remove(input_file);
+	teardown_fixture(fix);
+}
+
+static void test_set_global_vars_out_of_range(void)
+{
+	struct fixture *fix = init_fixture();
+
+	SYS_FAIL(out,
+		 "%s set_global_vars.bpf.o -G \"var_s32 = 2147483648\" -vl2 2> %s",
+		 fix->veristat, fix->tmpfile);
+
+	read(fix->fd, fix->output, fix->sz);
+	__CHECK_STR("is out of range [-2147483648; 2147483647]", "out of range");
+
+out:
+	teardown_fixture(fix);
+}
+
+void test_veristat(void)
+{
+	if (test__start_subtest("set_global_vars_succeeds"))
+		test_set_global_vars_succeeds();
+
+	if (test__start_subtest("set_global_vars_out_of_range"))
+		test_set_global_vars_out_of_range();
+
+	if (test__start_subtest("set_global_vars_from_file_succeeds"))
+		test_set_global_vars_from_file_succeeds();
+}
+
+#undef __CHECK_STR
diff --git a/tools/testing/selftests/bpf/progs/set_global_vars.c b/tools/testing/selftests/bpf/progs/set_global_vars.c
new file mode 100644
index 000000000000..9adb5ba4cd4d
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/set_global_vars.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2025 Meta Platforms, Inc. and affiliates. */
+#include "bpf_experimental.h"
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+#include <stdbool.h>
+
+char _license[] SEC("license") = "GPL";
+
+enum Enum { EA1 = 0, EA2 = 11 };
+enum Enumu64 {EB1 = 0llu, EB2 = 12llu };
+enum Enums64 { EC1 = 0ll, EC2 = 13ll };
+
+const volatile __s64 var_s64 = -1;
+const volatile __u64 var_u64 = 0;
+const volatile __s32 var_s32 = -1;
+const volatile __u32 var_u32 = 0;
+const volatile __s16 var_s16 = -1;
+const volatile __u16 var_u16 = 0;
+const volatile __s8 var_s8 = -1;
+const volatile __u8 var_u8 = 0;
+const volatile enum Enum var_ea = EA1;
+const volatile enum Enumu64 var_eb = EB1;
+const volatile enum Enums64 var_ec = EC1;
+const volatile bool var_b = false;
+
+char arr[4] = {0};
+
+SEC("socket")
+int test_set_globals(void *ctx)
+{
+	volatile __s8 a;
+
+	a = var_s64;
+	a = var_u64;
+	a = var_s32;
+	a = var_u32;
+	a = var_s16;
+	a = var_u16;
+	a = var_s8;
+	a = var_u8;
+	a = var_ea;
+	a = var_eb;
+	a = var_ec;
+	a = var_b;
+	return a;
+}
diff --git a/tools/testing/selftests/bpf/test_progs.h b/tools/testing/selftests/bpf/test_progs.h
index 404d0d4915d5..870694f2a359 100644
--- a/tools/testing/selftests/bpf/test_progs.h
+++ b/tools/testing/selftests/bpf/test_progs.h
@@ -427,6 +427,14 @@ void hexdump(const char *prefix, const void *buf, size_t len);
 			goto goto_label;				\
 	})
 
+#define SYS_FAIL(goto_label, fmt, ...)					\
+	({								\
+		char cmd[1024];						\
+		snprintf(cmd, sizeof(cmd), fmt, ##__VA_ARGS__);		\
+		if (!ASSERT_NEQ(0, system(cmd), cmd))			\
+			goto goto_label;				\
+	})
+
 #define ALL_TO_DEV_NULL " >/dev/null 2>&1"
 
 #define SYS_NOFAIL(fmt, ...)						\