From be983f44274f575e42025130e3c62b8718b0a29a Mon Sep 17 00:00:00 2001 From: Andrii Nakryiko <andrii@kernel.org> Date: Thu, 6 Apr 2023 16:42:04 -0700 Subject: [PATCH] selftests/bpf: Add testing of log_buf==NULL condition for BPF_PROG_LOAD Add few extra test conditions to validate that it's ok to pass log_buf==NULL and log_size==0 to BPF_PROG_LOAD command with the intent to get log_true_size without providing a buffer. Test that log_buf==NULL condition *does not* return -ENOSPC. Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Lorenz Bauer <lmb@isovalent.com> Link: https://lore.kernel.org/bpf/20230406234205.323208-19-andrii@kernel.org --- .../selftests/bpf/prog_tests/verifier_log.c | 23 +++++++++++++++++++ 1 file changed, 23 insertions(+) diff --git a/tools/testing/selftests/bpf/prog_tests/verifier_log.c b/tools/testing/selftests/bpf/prog_tests/verifier_log.c index 2ec82fc60c03..9ae0ac6e3b25 100644 --- a/tools/testing/selftests/bpf/prog_tests/verifier_log.c +++ b/tools/testing/selftests/bpf/prog_tests/verifier_log.c @@ -178,26 +178,47 @@ static void verif_log_subtest(const char *name, bool expect_load_error, int log_ opts.log_buf = logs.buf; opts.log_level = log_level | 8; /* BPF_LOG_FIXED */ opts.log_size = sizeof(logs.buf); + opts.log_true_size = 0; res = load_prog(&opts, expect_load_error); ASSERT_NEQ(res, -ENOSPC, "prog_load_res_fixed"); log_true_sz_fixed = opts.log_true_size; ASSERT_GT(log_true_sz_fixed, 0, "log_true_sz_fixed"); + /* (FIXED, NULL) get actual log size */ + opts.log_buf = NULL; + opts.log_level = log_level | 8; /* BPF_LOG_FIXED */ + opts.log_size = 0; + opts.log_true_size = 0; + res = load_prog(&opts, expect_load_error); + ASSERT_NEQ(res, -ENOSPC, "prog_load_res_fixed_null"); + ASSERT_EQ(opts.log_true_size, log_true_sz_fixed, "log_sz_fixed_null_eq"); + /* (ROLLING) get actual log size */ opts.log_buf = logs.buf; opts.log_level = log_level; opts.log_size = sizeof(logs.buf); + opts.log_true_size = 0; res = load_prog(&opts, expect_load_error); ASSERT_NEQ(res, -ENOSPC, "prog_load_res_rolling"); log_true_sz_rolling = opts.log_true_size; ASSERT_EQ(log_true_sz_rolling, log_true_sz_fixed, "log_true_sz_eq"); + /* (ROLLING, NULL) get actual log size */ + opts.log_buf = NULL; + opts.log_level = log_level; + opts.log_size = 0; + opts.log_true_size = 0; + res = load_prog(&opts, expect_load_error); + ASSERT_NEQ(res, -ENOSPC, "prog_load_res_rolling_null"); + ASSERT_EQ(opts.log_true_size, log_true_sz_rolling, "log_true_sz_null_eq"); + /* (FIXED) expect -ENOSPC for one byte short log */ opts.log_buf = logs.buf; opts.log_level = log_level | 8; /* BPF_LOG_FIXED */ opts.log_size = log_true_sz_fixed - 1; + opts.log_true_size = 0; res = load_prog(&opts, true /* should fail */); ASSERT_EQ(res, -ENOSPC, "prog_load_res_too_short_fixed"); @@ -205,6 +226,7 @@ static void verif_log_subtest(const char *name, bool expect_load_error, int log_ opts.log_buf = logs.buf; opts.log_level = log_level | 8; /* BPF_LOG_FIXED */ opts.log_size = log_true_sz_fixed; + opts.log_true_size = 0; res = load_prog(&opts, expect_load_error); ASSERT_NEQ(res, -ENOSPC, "prog_load_res_just_right_fixed"); @@ -219,6 +241,7 @@ static void verif_log_subtest(const char *name, bool expect_load_error, int log_ opts.log_buf = logs.buf; opts.log_level = log_level; opts.log_size = log_true_sz_rolling; + opts.log_true_size = 0; res = load_prog(&opts, expect_load_error); ASSERT_NEQ(res, -ENOSPC, "prog_load_res_just_right_rolling");