bpf: allow to specify log level and reduce it for test_verifier

For the test_verifier case, it's quite hard to parse log level 2 to
figure out what's causing an issue when used to log level 1. We do
want to use bpf_verify_program() in order to simulate some of the
tests with strict alignment. So just add an argument to pass the level
and put it to 1 for test_verifier.

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 7e0405e..412a7c8 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -120,7 +120,7 @@
 int bpf_verify_program(enum bpf_prog_type type, const struct bpf_insn *insns,
 		       size_t insns_cnt, int strict_alignment,
 		       const char *license, __u32 kern_version,
-		       char *log_buf, size_t log_buf_sz)
+		       char *log_buf, size_t log_buf_sz, int log_level)
 {
 	union bpf_attr attr;
 
@@ -131,7 +131,7 @@
 	attr.license = ptr_to_u64(license);
 	attr.log_buf = ptr_to_u64(log_buf);
 	attr.log_size = log_buf_sz;
-	attr.log_level = 2;
+	attr.log_level = log_level;
 	log_buf[0] = 0;
 	attr.kern_version = kern_version;
 	attr.prog_flags = strict_alignment ? BPF_F_STRICT_ALIGNMENT : 0;