diff --git a/tools/testing/selftests/bpf/test_verifier.c b/tools/testing/selftests/bpf/test_verifier.c
index 59bfa6201d1d..58b5a349d3ba 100644
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@ -88,6 +88,10 @@ struct bpf_test {
 	int fixup_map_event_output[MAX_FIXUPS];
 	int fixup_map_reuseport_array[MAX_FIXUPS];
 	int fixup_map_ringbuf[MAX_FIXUPS];
+	/* Expected verifier log output for result REJECT or VERBOSE_ACCEPT.
+	 * Can be a tab-separated sequence of expected strings. An empty string
+	 * means no log verification.
+	 */
 	const char *errstr;
 	const char *errstr_unpriv;
 	uint32_t insn_processed;
@@ -995,13 +999,19 @@ static int do_prog_test_run(int fd_prog, bool unpriv, uint32_t expected_val,
 	return 0;
 }
 
+/* Returns true if every part of exp (tab-separated) appears in log, in order.
+ *
+ * If exp is an empty string, returns true.
+ */
 static bool cmp_str_seq(const char *log, const char *exp)
 {
-	char needle[80];
+	char needle[200];
 	const char *p, *q;
 	int len;
 
 	do {
+		if (!strlen(exp))
+			break;
 		p = strchr(exp, '\t');
 		if (!p)
 			p = exp + strlen(exp);
@@ -1015,7 +1025,7 @@ static bool cmp_str_seq(const char *log, const char *exp)
 		needle[len] = 0;
 		q = strstr(log, needle);
 		if (!q) {
-			printf("FAIL\nUnexpected verifier log in successful load!\n"
+			printf("FAIL\nUnexpected verifier log!\n"
 			       "EXP: %s\nRES:\n", needle);
 			return false;
 		}
@@ -1130,7 +1140,7 @@ static void do_test_single(struct bpf_test *test, bool unpriv,
 			printf("FAIL\nUnexpected success to load!\n");
 			goto fail_log;
 		}
-		if (!expected_err || !strstr(bpf_vlog, expected_err)) {
+		if (!expected_err || !cmp_str_seq(bpf_vlog, expected_err)) {
 			printf("FAIL\nUnexpected error message!\n\tEXP: %s\n\tRES: %s\n",
 			      expected_err, bpf_vlog);
 			goto fail_log;