[PATCH bpf-next] libbpf: Fix uretprobe.multi.s programs auto attachment

[Jiri Olsa <jolsa@kernel.org>]

As reported by Andrii we don't currently recognize uretprobe.multi.s
programs as return probes due to using (wrong) strcmp function.

Using strncmp instead to match uretprobe.multi as prefix.

Tests are passing, because the return program was executed
as entry program and all counts were incremented properly.

Reported-by: Andrii Nakryiko <andrii@kernel.org>
Closes: https://lore.kernel.org/bpf/CAEf4BzYpH_2f0eHwQG205Q_4hewbtC9OrVSA-_jn6ysz53QbBg@mail.gmail.com/
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
 tools/lib/bpf/libbpf.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 4f29e06c2641..08e110392516 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -11688,7 +11688,7 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru
 		ret = 0;
 		break;
 	case 3:
-		opts.retprobe = strcmp(probe_type, "uretprobe.multi") == 0;
+		opts.retprobe = strncmp(probe_type, "uretprobe.multi", sizeof("uretprobe.multi") - 1) == 0;
 		*link = bpf_program__attach_uprobe_multi(prog, -1, binary_path, func_name, &opts);
 		ret = libbpf_get_error(*link);
 		break;
-- 
2.46.0