From: Jianlin Lv <Jianlin.Lv@arm.com>
Date: Thu, 6 Aug 2020 18:42:24 +0800
Subject: bpf: Fix compilation warning of selftests
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Content-Transfer-Encoding: 8bit
Patch-mainline: v5.9-rc1
Git-commit: 929e54a989680c6f134b02293732030b897475dc
References: bsc#1177028
Clang compiler version: 12.0.0
The following warning appears during the selftests/bpf compilation:
prog_tests/send_signal.c:51:3: warning: ignoring return value of ‘write’,
declared with attribute warn_unused_result [-Wunused-result]
51 | write(pipe_c2p[1], buf, 1);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
prog_tests/send_signal.c:54:3: warning: ignoring return value of ‘read’,
declared with attribute warn_unused_result [-Wunused-result]
54 | read(pipe_p2c[0], buf, 1);
| ^~~~~~~~~~~~~~~~~~~~~~~~~
......
prog_tests/stacktrace_build_id_nmi.c:13:2: warning: ignoring return value
of ‘fscanf’,declared with attribute warn_unused_result [-Wunused-resul]
13 | fscanf(f, "%llu", &sample_freq);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
test_tcpnotify_user.c:133:2: warning:ignoring return value of ‘system’,
declared with attribute warn_unused_result [-Wunused-result]
133 | system(test_script);
| ^~~~~~~~~~~~~~~~~~~
test_tcpnotify_user.c:138:2: warning:ignoring return value of ‘system’,
declared with attribute warn_unused_result [-Wunused-result]
138 | system(test_script);
| ^~~~~~~~~~~~~~~~~~~
test_tcpnotify_user.c:143:2: warning:ignoring return value of ‘system’,
declared with attribute warn_unused_result [-Wunused-result]
143 | system(test_script);
| ^~~~~~~~~~~~~~~~~~~
Add code that fix compilation warning about ignoring return value and
handles any errors; Check return value of library`s API make the code
more secure.
Signed-off-by: Jianlin Lv <Jianlin.Lv@arm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200806104224.95306-1-Jianlin.Lv@arm.com
Acked-by: Gary Lin <glin@suse.com>
---
tools/testing/selftests/bpf/prog_tests/send_signal.c | 18 ++++------
tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c | 4 +-
tools/testing/selftests/bpf/test_tcpnotify_user.c | 13 +++++--
3 files changed, 21 insertions(+), 14 deletions(-)
--- a/tools/testing/selftests/bpf/prog_tests/send_signal.c
+++ b/tools/testing/selftests/bpf/prog_tests/send_signal.c
@@ -48,21 +48,19 @@ static void test_send_signal_common(stru
close(pipe_p2c[1]); /* close write */
/* notify parent signal handler is installed */
- write(pipe_c2p[1], buf, 1);
+ CHECK(write(pipe_c2p[1], buf, 1) != 1, "pipe_write", "err %d\n", -errno);
/* make sure parent enabled bpf program to send_signal */
- read(pipe_p2c[0], buf, 1);
+ CHECK(read(pipe_p2c[0], buf, 1) != 1, "pipe_read", "err %d\n", -errno);
/* wait a little for signal handler */
sleep(1);
- if (sigusr1_received)
- write(pipe_c2p[1], "2", 1);
- else
- write(pipe_c2p[1], "0", 1);
+ buf[0] = sigusr1_received ? '2' : '0';
+ CHECK(write(pipe_c2p[1], buf, 1) != 1, "pipe_write", "err %d\n", -errno);
/* wait for parent notification and exit */
- read(pipe_p2c[0], buf, 1);
+ CHECK(read(pipe_p2c[0], buf, 1) != 1, "pipe_read", "err %d\n", -errno);
close(pipe_c2p[1]);
close(pipe_p2c[0]);
@@ -99,7 +97,7 @@ static void test_send_signal_common(stru
}
/* wait until child signal handler installed */
- read(pipe_c2p[0], buf, 1);
+ CHECK(read(pipe_c2p[0], buf, 1) != 1, "pipe_read", "err %d\n", -errno);
/* trigger the bpf send_signal */
skel->bss->pid = pid;
@@ -107,7 +105,7 @@ static void test_send_signal_common(stru
skel->bss->signal_thread = signal_thread;
/* notify child that bpf program can send_signal now */
- write(pipe_p2c[1], buf, 1);
+ CHECK(write(pipe_p2c[1], buf, 1) != 1, "pipe_write", "err %d\n", -errno);
/* wait for result */
err = read(pipe_c2p[0], buf, 1);
@@ -121,7 +119,7 @@ static void test_send_signal_common(stru
CHECK(buf[0] != '2', test_name, "incorrect result\n");
/* notify child safe to exit */
- write(pipe_p2c[1], buf, 1);
+ CHECK(write(pipe_p2c[1], buf, 1) != 1, "pipe_write", "err %d\n", -errno);
disable_pmu:
close(pmu_fd);
--- a/tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c
+++ b/tools/testing/selftests/bpf/prog_tests/stacktrace_build_id_nmi.c
@@ -6,11 +6,13 @@ static __u64 read_perf_max_sample_freq(v
{
__u64 sample_freq = 5000; /* fallback to 5000 on error */
FILE *f;
+ __u32 duration = 0;
f = fopen("/proc/sys/kernel/perf_event_max_sample_rate", "r");
if (f == NULL)
return sample_freq;
- fscanf(f, "%llu", &sample_freq);
+ CHECK(fscanf(f, "%llu", &sample_freq) != 1, "Get max sample rate",
+ "return default value: 5000,err %d\n", -errno);
fclose(f);
return sample_freq;
}
--- a/tools/testing/selftests/bpf/test_tcpnotify_user.c
+++ b/tools/testing/selftests/bpf/test_tcpnotify_user.c
@@ -124,17 +124,24 @@ int main(int argc, char **argv)
sprintf(test_script,
"iptables -A INPUT -p tcp --dport %d -j DROP",
TESTPORT);
- system(test_script);
+ if (system(test_script)) {
+ printf("FAILED: execute command: %s, err %d\n", test_script, -errno);
+ goto err;
+ }
sprintf(test_script,
"nc 127.0.0.1 %d < /etc/passwd > /dev/null 2>&1 ",
TESTPORT);
- system(test_script);
+ if (system(test_script))
+ printf("execute command: %s, err %d\n", test_script, -errno);
sprintf(test_script,
"iptables -D INPUT -p tcp --dport %d -j DROP",
TESTPORT);
- system(test_script);
+ if (system(test_script)) {
+ printf("FAILED: execute command: %s, err %d\n", test_script, -errno);
+ goto err;
+ }
rv = bpf_map_lookup_elem(bpf_map__fd(global_map), &key, &g);
if (rv != 0) {