[bpf-next PATCH] bpf, selftests: fix warning in snprintf_btf where system() call unchecked
From: John Fastabend <john.fastabend@gmail.com>
Date: 2020-09-29 20:08:15
Also in:
bpf
Subsystem:
bpf [general] (safe dynamic programs and tools), bpf [selftests] (test runners & infrastructure), kernel selftest framework, the rest · Maintainers:
Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko, Eduard Zingerman, Kumar Kartikeya Dwivedi, Shuah Khan, Linus Torvalds
On my systems system() calls are marked with warn_unused_result
apparently. So without error checking we get this warning,
./prog_tests/snprintf_btf.c:30:9: warning: ignoring return value
of ‘system’, declared with attribute warn_unused_result[-Wunused-result]
Also it seems like a good idea to check the return value anyways
to ensure ping exists even if its seems unlikely.
Fixes: 076a95f5aff2c ("selftests/bpf: Add bpf_snprintf_btf helper tests")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
---
.../selftests/bpf/prog_tests/snprintf_btf.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c b/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c
index 3c63a7003db4..686b40f11a45 100644
--- a/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c
+++ b/tools/testing/selftests/bpf/prog_tests/snprintf_btf.c@@ -27,7 +27,9 @@ void test_snprintf_btf(void) goto cleanup; /* generate receive event */ - (void) system("ping -c 1 127.0.0.1 > /dev/null"); + err = system("ping -c 1 127.0.0.1 > /dev/null"); + if (CHECK(err, "system", "ping failed: %d\n", err)) + goto cleanup; if (bss->skip) { printf("%s:SKIP:no __builtin_btf_type_id\n", __func__);