selftests/bpf: add a test for overlapping packet range checks

add simple C test case for llvm and verifier range check fix from
commit b1977682a385 ("bpf: improve verifier packet range checks")

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 138 insertions, 0 deletions

diff --git a/tools/testing/selftests/bpf/test_progs.c b/tools/testing/selftests/bpf/test_progs.c
new file mode 100644
index 000000000000..1d9a310e71e5
--- /dev/null
+++ b/tools/testing/selftests/bpf/test_progs.c
@@ -0,0 +1,138 @@
+/* Copyright (c) 2017 Facebook
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ */
+#include <stdio.h>
+#include <unistd.h>
+#include <errno.h>
+#include <string.h>
+#include <assert.h>
+#include <stdlib.h>
+
+#include <linux/types.h>
+typedef __u16 __sum16;
+#include <arpa/inet.h>
+#include <linux/if_ether.h>
+#include <linux/if_packet.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/tcp.h>
+
+#include <sys/wait.h>
+#include <sys/resource.h>
+
+#include <linux/bpf.h>
+#include <linux/err.h>
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#define _htons __builtin_bswap16
+
+static int error_cnt, pass_cnt;
+
+/* ipv4 test vector */
+static struct {
+	struct ethhdr eth;
+	struct iphdr iph;
+	struct tcphdr tcp;
+} __packed pkt_v4 = {
+	.eth.h_proto = _htons(ETH_P_IP),
+	.iph.ihl = 5,
+	.iph.protocol = 6,
+	.tcp.urg_ptr = 123,
+};
+
+/* ipv6 test vector */
+static struct {
+	struct ethhdr eth;
+	struct ipv6hdr iph;
+	struct tcphdr tcp;
+} __packed pkt_v6 = {
+	.eth.h_proto = _htons(ETH_P_IPV6),
+	.iph.nexthdr = 6,
+	.tcp.urg_ptr = 123,
+};
+
+#define CHECK(condition, tag, format...) ({				\
+	int __ret = !!(condition);					\
+	if (__ret) {							\
+		error_cnt++;						\
+		printf("%s:FAIL:%s ", __func__, tag);			\
+		printf(format);						\
+	} else {							\
+		pass_cnt++;						\
+		printf("%s:PASS:%s %d nsec\n", __func__, tag, duration);\
+	}								\
+})
+
+static int bpf_prog_load(const char *file, enum bpf_prog_type type,
+			 struct bpf_object **pobj, int *prog_fd)
+{
+	struct bpf_program *prog;
+	struct bpf_object *obj;
+	int err;
+
+	obj = bpf_object__open(file);
+	if (IS_ERR(obj)) {
+		error_cnt++;
+		return -ENOENT;
+	}
+
+	prog = bpf_program__next(NULL, obj);
+	if (!prog) {
+		bpf_object__close(obj);
+		error_cnt++;
+		return -ENOENT;
+	}
+
+	bpf_program__set_type(prog, type);
+	err = bpf_object__load(obj);
+	if (err) {
+		bpf_object__close(obj);
+		error_cnt++;
+		return -EINVAL;
+	}
+
+	*pobj = obj;
+	*prog_fd = bpf_program__fd(prog);
+	return 0;
+}
+
+static void test_pkt_access(void)
+{
+	const char *file = "./test_pkt_access.o";
+	struct bpf_object *obj;
+	__u32 duration, retval;
+	int err, prog_fd;
+
+	err = bpf_prog_load(file, BPF_PROG_TYPE_SCHED_CLS, &obj, &prog_fd);
+	if (err)
+		return;
+
+	err = bpf_prog_test_run(prog_fd, 100000, &pkt_v4, sizeof(pkt_v4),
+				NULL, NULL, &retval, &duration);
+	CHECK(err || errno || retval, "ipv4",
+	      "err %d errno %d retval %d duration %d\n",
+	      err, errno, retval, duration);
+
+	err = bpf_prog_test_run(prog_fd, 100000, &pkt_v6, sizeof(pkt_v6),
+				NULL, NULL, &retval, &duration);
+	CHECK(err || errno || retval, "ipv6",
+	      "err %d errno %d retval %d duration %d\n",
+	      err, errno, retval, duration);
+	bpf_object__close(obj);
+}
+
+int main(void)
+{
+	struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
+
+	setrlimit(RLIMIT_MEMLOCK, &rinf);
+
+	test_pkt_access();
+
+	printf("Summary: %d PASSED, %d FAILED\n", pass_cnt, error_cnt);
+	return 0;
+}