bpf: Always test unprivileged programs
If selftests are run as root, then execute the unprivileged checks as
well. This switch from 243 to 368 tests.
The test numbers are suffixed with "/u" when executed as unprivileged or
with "/p" when executed as privileged.
The geteuid() check is replaced with a capability check.
Handling capabilities requires the libcap dependency.
Signed-off-by: Mickaël Salaün <mic@digikod.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index c470c73..f3d65ad 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -1,4 +1,4 @@
-CFLAGS += -Wall -O2 -I../../../include/uapi
+CFLAGS += -Wall -O2 -lcap -I../../../include/uapi
test_objs = test_verifier test_tag test_maps test_lru_map test_lpm_map
diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 71f6407..878bd60 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -16,6 +16,7 @@
#include <stdbool.h>
#include <sched.h>
+#include <sys/capability.h>
#include <sys/resource.h>
#include <linux/unistd.h>
@@ -4574,6 +4575,55 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
goto close_fds;
}
+static bool is_admin(void)
+{
+ cap_t caps;
+ cap_flag_value_t sysadmin = CAP_CLEAR;
+ const cap_value_t cap_val = CAP_SYS_ADMIN;
+
+ if (!CAP_IS_SUPPORTED(CAP_SETFCAP)) {
+ perror("cap_get_flag");
+ return false;
+ }
+ caps = cap_get_proc();
+ if (!caps) {
+ perror("cap_get_proc");
+ return false;
+ }
+ if (cap_get_flag(caps, cap_val, CAP_EFFECTIVE, &sysadmin))
+ perror("cap_get_flag");
+ if (cap_free(caps))
+ perror("cap_free");
+ return (sysadmin == CAP_SET);
+}
+
+static int set_admin(bool admin)
+{
+ cap_t caps;
+ const cap_value_t cap_val = CAP_SYS_ADMIN;
+ int ret = -1;
+
+ caps = cap_get_proc();
+ if (!caps) {
+ perror("cap_get_proc");
+ return -1;
+ }
+ if (cap_set_flag(caps, CAP_EFFECTIVE, 1, &cap_val,
+ admin ? CAP_SET : CAP_CLEAR)) {
+ perror("cap_set_flag");
+ goto out;
+ }
+ if (cap_set_proc(caps)) {
+ perror("cap_set_proc");
+ goto out;
+ }
+ ret = 0;
+out:
+ if (cap_free(caps))
+ perror("cap_free");
+ return ret;
+}
+
static int do_test(bool unpriv, unsigned int from, unsigned int to)
{
int i, passes = 0, errors = 0;
@@ -4584,11 +4634,19 @@ static int do_test(bool unpriv, unsigned int from, unsigned int to)
/* Program types that are not supported by non-root we
* skip right away.
*/
- if (unpriv && test->prog_type)
- continue;
+ if (!test->prog_type) {
+ if (!unpriv)
+ set_admin(false);
+ printf("#%d/u %s ", i, test->descr);
+ do_test_single(test, true, &passes, &errors);
+ if (!unpriv)
+ set_admin(true);
+ }
- printf("#%d %s ", i, test->descr);
- do_test_single(test, unpriv, &passes, &errors);
+ if (!unpriv) {
+ printf("#%d/p %s ", i, test->descr);
+ do_test_single(test, false, &passes, &errors);
+ }
}
printf("Summary: %d PASSED, %d FAILED\n", passes, errors);
@@ -4600,7 +4658,7 @@ int main(int argc, char **argv)
struct rlimit rinf = { RLIM_INFINITY, RLIM_INFINITY };
struct rlimit rlim = { 1 << 20, 1 << 20 };
unsigned int from = 0, to = ARRAY_SIZE(tests);
- bool unpriv = geteuid() != 0;
+ bool unpriv = !is_admin();
if (argc == 3) {
unsigned int l = atoi(argv[argc - 2]);