Re: [PATCH bpf v2 2/2] bpf/selftests: test that kernel rejects a TCP CC with an invalid license
From: Martin KaFai Lau <hidden>
Date: 2021-03-25 23:00:17
Also in:
bpf
On Thu, Mar 25, 2021 at 10:11:22PM +0100, Toke Høiland-Jørgensen wrote:
quoted hunk ↗ jump to hunk
This adds a selftest to check that the verifier rejects a TCP CC struct_ops with a non-GPL license. v2: - Use a minimal struct_ops BPF program instead of rewriting bpf_dctcp's license in memory. - Check for the verifier reject message instead of just the return code. Signed-off-by: Toke Høiland-Jørgensen <redacted> --- .../selftests/bpf/prog_tests/bpf_tcp_ca.c | 44 +++++++++++++++++++ .../selftests/bpf/progs/bpf_nogpltcp.c | 19 ++++++++ 2 files changed, 63 insertions(+) create mode 100644 tools/testing/selftests/bpf/progs/bpf_nogpltcp.cdiff --git a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c index 37c5494a0381..a09c716528e1 100644 --- a/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c +++ b/tools/testing/selftests/bpf/prog_tests/bpf_tcp_ca.c@@ -6,6 +6,7 @@ #include <test_progs.h> #include "bpf_dctcp.skel.h" #include "bpf_cubic.skel.h" +#include "bpf_nogpltcp.skel.h" #define min(a, b) ((a) < (b) ? (a) : (b))@@ -227,10 +228,53 @@ static void test_dctcp(void) bpf_dctcp__destroy(dctcp_skel); } +static char *err_str = NULL; +static bool found = false;
Nit. These two inits are not needed.
+
+static int libbpf_debug_print(enum libbpf_print_level level,
+ const char *format, va_list args)
+{
+ char *log_buf;
+
+ if (level != LIBBPF_WARN ||
+ strcmp(format, "libbpf: \n%s\n")) {
+ vprintf(format, args);
+ return 0;
+ }
+
+ log_buf = va_arg(args, char *);
+ if (!log_buf)
+ goto out;
+ if (err_str && strstr(log_buf, err_str) != NULL)
+ found = true;
+out:
+ printf(format, log_buf);
+ return 0;
+}
+
+static void test_invalid_license(void)
+{
+ libbpf_print_fn_t old_print_fn = NULL;Nit. Same here. Not need to init NULL. Others lgtm. Acked-by: Martin KaFai Lau <redacted>
+ struct bpf_nogpltcp *skel; + + err_str = "struct ops programs must have a GPL compatible license"; + old_print_fn = libbpf_set_print(libbpf_debug_print); + + skel = bpf_nogpltcp__open_and_load(); + if (CHECK(skel, "bpf_nogplgtcp__open_and_load()", "didn't fail\n")) + bpf_nogpltcp__destroy(skel); + + CHECK(!found, "errmsg check", "expected string '%s'", err_str); + + libbpf_set_print(old_print_fn); +}