selftests/bpf: Add test for freplace program with expected_attach_type

This adds a new selftest that tests the ability to attach an freplace
program to a program type that relies on the expected_attach_type of the
target program to pass verification.

Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158773526831.293902.16011743438619684815.stgit@toke.dk

diff --git a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c
index cde463a..c264251 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c
+++ b/tools/testing/selftests/bpf/prog_tests/fexit_bpf2bpf.c
@@ -5,7 +5,8 @@
 static void test_fexit_bpf2bpf_common(const char *obj_file,
                                      const char *target_obj_file,
                                      int prog_cnt,
-                                     const char **prog_name)
+                                     const char **prog_name,
+                                     bool run_prog)
 {
        struct bpf_object *obj = NULL, *pkt_obj;
        int err, pkt_fd, i;
@@ -18,7 +19,8 @@ static void test_fexit_bpf2bpf_common(const char *obj_file,
 
        err = bpf_prog_load(target_obj_file, BPF_PROG_TYPE_UNSPEC,
                            &pkt_obj, &pkt_fd);
-       if (CHECK(err, "prog_load sched cls", "err %d errno %d\n", err, errno))
+       if (CHECK(err, "tgt_prog_load", "file %s err %d errno %d\n",
+                 target_obj_file, err, errno))
                return;
        DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts,
                            .attach_prog_fd = pkt_fd,
@@ -33,7 +35,7 @@ static void test_fexit_bpf2bpf_common(const char *obj_file,
 
        obj = bpf_object__open_file(obj_file, &opts);
        if (CHECK(IS_ERR_OR_NULL(obj), "obj_open",
-                 "failed to open fexit_bpf2bpf: %ld\n",
+                 "failed to open %s: %ld\n", obj_file,
                  PTR_ERR(obj)))
                goto close_prog;
 
@@ -49,6 +51,10 @@ static void test_fexit_bpf2bpf_common(const char *obj_file,
                if (CHECK(IS_ERR(link[i]), "attach_trace", "failed to link\n"))
                        goto close_prog;
        }
+
+       if (!run_prog)
+               goto close_prog;
+
        data_map = bpf_object__find_map_by_name(obj, "fexit_bp.bss");
        if (CHECK(!data_map, "find_data_map", "data map not found\n"))
                goto close_prog;
@@ -89,7 +95,7 @@ static void test_target_no_callees(void)
        test_fexit_bpf2bpf_common("./fexit_bpf2bpf_simple.o",
                                  "./test_pkt_md_access.o",
                                  ARRAY_SIZE(prog_name),
-                                 prog_name);
+                                 prog_name, true);
 }
 
 static void test_target_yes_callees(void)
@@ -103,7 +109,7 @@ static void test_target_yes_callees(void)
        test_fexit_bpf2bpf_common("./fexit_bpf2bpf.o",
                                  "./test_pkt_access.o",
                                  ARRAY_SIZE(prog_name),
-                                 prog_name);
+                                 prog_name, true);
 }
 
 static void test_func_replace(void)
@@ -120,7 +126,18 @@ static void test_func_replace(void)
        test_fexit_bpf2bpf_common("./fexit_bpf2bpf.o",
                                  "./test_pkt_access.o",
                                  ARRAY_SIZE(prog_name),
-                                 prog_name);
+                                 prog_name, true);
+}
+
+static void test_func_replace_verify(void)
+{
+       const char *prog_name[] = {
+               "freplace/do_bind",
+       };
+       test_fexit_bpf2bpf_common("./freplace_connect4.o",
+                                 "./connect4_prog.o",
+                                 ARRAY_SIZE(prog_name),
+                                 prog_name, false);
 }
 
 void test_fexit_bpf2bpf(void)
@@ -128,4 +145,5 @@ void test_fexit_bpf2bpf(void)
        test_target_no_callees();
        test_target_yes_callees();
        test_func_replace();
+       test_func_replace_verify();
 }

diff --git a/tools/testing/selftests/bpf/progs/connect4_prog.c b/tools/testing/selftests/bpf/progs/connect4_prog.c
index 7508511..ad3c498 100644 (file)
--- a/tools/testing/selftests/bpf/progs/connect4_prog.c
+++ b/tools/testing/selftests/bpf/progs/connect4_prog.c
@@ -18,11 +18,25 @@
 
 int _version SEC("version") = 1;
 
+__attribute__ ((noinline))
+int do_bind(struct bpf_sock_addr *ctx)
+{
+       struct sockaddr_in sa = {};
+
+       sa.sin_family = AF_INET;
+       sa.sin_port = bpf_htons(0);
+       sa.sin_addr.s_addr = bpf_htonl(SRC_REWRITE_IP4);
+
+       if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0)
+               return 0;
+
+       return 1;
+}
+
 SEC("cgroup/connect4")
 int connect_v4_prog(struct bpf_sock_addr *ctx)
 {
        struct bpf_sock_tuple tuple = {};
-       struct sockaddr_in sa;
        struct bpf_sock *sk;
 
        /* Verify that new destination is available. */
@@ -56,17 +70,7 @@ int connect_v4_prog(struct bpf_sock_addr *ctx)
        ctx->user_ip4 = bpf_htonl(DST_REWRITE_IP4);
        ctx->user_port = bpf_htons(DST_REWRITE_PORT4);
 
-       /* Rewrite source. */
-       memset(&sa, 0, sizeof(sa));
-
-       sa.sin_family = AF_INET;
-       sa.sin_port = bpf_htons(0);
-       sa.sin_addr.s_addr = bpf_htonl(SRC_REWRITE_IP4);
-
-       if (bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa)) != 0)
-               return 0;
-
-       return 1;
+       return do_bind(ctx) ? 1 : 0;
 }
 
 char _license[] SEC("license") = "GPL";

diff --git a/tools/testing/selftests/bpf/progs/freplace_connect4.c b/tools/testing/selftests/bpf/progs/freplace_connect4.c
new file mode 100644 (file)
index 0000000..a0ae842
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/freplace_connect4.c
@@ -0,0 +1,18 @@
+#include <linux/stddef.h>
+#include <linux/ipv6.h>
+#include <linux/bpf.h>
+#include <linux/in.h>
+#include <sys/socket.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_endian.h>
+
+SEC("freplace/do_bind")
+int new_do_bind(struct bpf_sock_addr *ctx)
+{
+  struct sockaddr_in sa = {};
+
+  bpf_bind(ctx, (struct sockaddr *)&sa, sizeof(sa));
+  return 0;
+}
+
+char _license[] SEC("license") = "GPL";