1 files changed, 158 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/test_varlen.c b/tools/testing/selftests/bpf/progs/test_varlen.c
new file mode 100644
index 000000000000..3987ff174f1f
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/test_varlen.c
@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright (c) 2020 Facebook */
+
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include <bpf/bpf_core_read.h>
+
+#define MAX_LEN 256
+
+char buf_in1[MAX_LEN] = {};
+char buf_in2[MAX_LEN] = {};
+
+int test_pid = 0;
+bool capture = false;
+
+/* .bss */
+__u64 payload1_len1 = 0;
+__u64 payload1_len2 = 0;
+__u64 total1 = 0;
+char payload1[MAX_LEN + MAX_LEN] = {};
+
+/* .data */
+int payload2_len1 = -1;
+int payload2_len2 = -1;
+int total2 = -1;
+char payload2[MAX_LEN + MAX_LEN] = { 1 };
+
+int payload3_len1 = -1;
+int payload3_len2 = -1;
+int total3= -1;
+char payload3[MAX_LEN + MAX_LEN] = { 1 };
+
+int payload4_len1 = -1;
+int payload4_len2 = -1;
+int total4= -1;
+char payload4[MAX_LEN + MAX_LEN] = { 1 };
+
+SEC("raw_tp/sys_enter")
+int handler64_unsigned(void *regs)
+{
+	int pid = bpf_get_current_pid_tgid() >> 32;
+	void *payload = payload1;
+	long len;
+
+	/* ignore irrelevant invocations */
+	if (test_pid != pid || !capture)
+		return 0;
+
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in1[0]);
+	if (len >= 0) {
+		payload += len;
+		payload1_len1 = len;
+	}
+
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in2[0]);
+	if (len >= 0) {
+		payload += len;
+		payload1_len2 = len;
+	}
+
+	total1 = payload - (void *)payload1;
+
+	return 0;
+}
+
+SEC("raw_tp/sys_exit")
+int handler64_signed(void *regs)
+{
+	int pid = bpf_get_current_pid_tgid() >> 32;
+	void *payload = payload3;
+	long len;
+
+	/* ignore irrelevant invocations */
+	if (test_pid != pid || !capture)
+		return 0;
+
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in1[0]);
+	if (len >= 0) {
+		payload += len;
+		payload3_len1 = len;
+	}
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in2[0]);
+	if (len >= 0) {
+		payload += len;
+		payload3_len2 = len;
+	}
+	total3 = payload - (void *)payload3;
+
+	return 0;
+}
+
+SEC("tp/raw_syscalls/sys_enter")
+int handler32_unsigned(void *regs)
+{
+	int pid = bpf_get_current_pid_tgid() >> 32;
+	void *payload = payload2;
+	u32 len;
+
+	/* ignore irrelevant invocations */
+	if (test_pid != pid || !capture)
+		return 0;
+
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in1[0]);
+	if (len <= MAX_LEN) {
+		payload += len;
+		payload2_len1 = len;
+	}
+
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in2[0]);
+	if (len <= MAX_LEN) {
+		payload += len;
+		payload2_len2 = len;
+	}
+
+	total2 = payload - (void *)payload2;
+
+	return 0;
+}
+
+SEC("tp/raw_syscalls/sys_exit")
+int handler32_signed(void *regs)
+{
+	int pid = bpf_get_current_pid_tgid() >> 32;
+	void *payload = payload4;
+	long len;
+
+	/* ignore irrelevant invocations */
+	if (test_pid != pid || !capture)
+		return 0;
+
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in1[0]);
+	if (len >= 0) {
+		payload += len;
+		payload4_len1 = len;
+	}
+	len = bpf_probe_read_kernel_str(payload, MAX_LEN, &buf_in2[0]);
+	if (len >= 0) {
+		payload += len;
+		payload4_len2 = len;
+	}
+	total4 = payload - (void *)payload4;
+
+	return 0;
+}
+
+SEC("tp/syscalls/sys_exit_getpid")
+int handler_exit(void *regs)
+{
+	long bla;
+
+	if (bpf_probe_read_kernel(&bla, sizeof(bla), 0))
+		return 1;
+	else
+		return 0;
+}
+
+char LICENSE[] SEC("license") = "GPL";