samples/bpf: Fix sockex3: missing BPF prog type

Commit Message

Rong Tao Oct. 27, 2022, 1:33 p.m. UTC

From: Rong Tao <[e-mail]>

since commit 450b167fb9be("libbpf: clean up SEC() handling"),
sec_def_matches() does not recognize "socket/xxx" as "socket", therefore,
the BPF program type is not recognized, we should add a custom program
type handler for "socket/xxx".

 $ cd samples/bpf
 $ sudo ./sockex3
 libbpf: prog 'bpf_func_PARSE_IP': missing BPF prog type, check ELF section name 'socket/3'
 libbpf: prog 'bpf_func_PARSE_IP': failed to load: -22
 libbpf: failed to load object './sockex3_kern.o'
 ERROR: loading BPF object file failed

Signed-off-by: Rong Tao <[e-mail]>
---
 samples/bpf/sockex3_user.c | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

Patch

diff --git a/samples/bpf/sockex3_user.c b/samples/bpf/sockex3_user.c
index cd6fa79df900..d18d7a3600b0 100644
--- a/samples/bpf/sockex3_user.c
+++ b/samples/bpf/sockex3_user.c
@@ -22,6 +22,14 @@  struct pair {
 	__u64 bytes;
 };
 
+static int socket_prog_type_id;
+
+__attribute__((destructor))
+static void unregister_socket_sec_handlers(void)
+{
+	libbpf_unregister_prog_handler(socket_prog_type_id);
+}
+
 int main(int argc, char **argv)
 {
 	int i, sock, key, fd, main_prog_fd, jmp_table_fd, hash_map_fd;
@@ -31,6 +39,13 @@  int main(int argc, char **argv)
 	char filename[256];
 	FILE *f;
 
+	LIBBPF_OPTS(libbpf_prog_handler_opts, socket_opts,
+		.cookie = 1,
+	);
+
+	socket_prog_type_id = libbpf_register_prog_handler("socket/",
+			BPF_PROG_TYPE_SOCKET_FILTER, 0, &socket_opts);
+
 	snprintf(filename, sizeof(filename), "%s_kern.o", argv[0]);
 
 	obj = bpf_object__open_file(filename, NULL);