[PATCH bpf] tools: bpftool: return from do_event_pipe() on bad arguments

[Quentin Monnet <quentin.monnet@netronome.com>]

When command line parsing fails in the while loop in do_event_pipe()
because the number of arguments is incorrect or because the keyword is
unknown, an error message is displayed, but bpfool remains stucked in
the loop. Make sure we exit the loop upon failure.

Fixes: f412eed9dfde ("tools: bpftool: add simple perf event output reader")
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
---
 tools/bpf/bpftool/map_perf_ring.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/tools/bpf/bpftool/map_perf_ring.c b/tools/bpf/bpftool/map_perf_ring.c
index 1832100d1b27..6d41323be291 100644
--- a/tools/bpf/bpftool/map_perf_ring.c
+++ b/tools/bpf/bpftool/map_perf_ring.c
@@ -194,8 +194,10 @@ int do_event_pipe(int argc, char **argv)
 	}
 
 	while (argc) {
-		if (argc < 2)
+		if (argc < 2) {
 			BAD_ARG();
+			goto err_close_map;
+		}
 
 		if (is_prefix(*argv, "cpu")) {
 			char *endptr;
@@ -221,6 +223,7 @@ int do_event_pipe(int argc, char **argv)
 			NEXT_ARG();
 		} else {
 			BAD_ARG();
+			goto err_close_map;
 		}
 
 		do_all = false;
-- 
2.14.1