diff --git a/test/nvme/aer/aer.c b/test/nvme/aer/aer.c
index 10b5b1c2a..afee2909a 100644
--- a/test/nvme/aer/aer.c
+++ b/test/nvme/aer/aer.c
@@ -36,6 +36,7 @@
 #include "spdk/log.h"
 #include "spdk/nvme.h"
 #include "spdk/env.h"
+#include "spdk/string.h"
 
 #define MAX_DEVS 64
 
@@ -303,6 +304,7 @@ static int
 parse_args(int argc, char **argv)
 {
 	int op, rc;
+	long int val;
 
 	g_trid.trtype = SPDK_NVME_TRANSPORT_PCIE;
 	snprintf(g_trid.subnqn, sizeof(g_trid.subnqn), "%s", SPDK_NVMF_DISCOVERY_NQN);
@@ -310,7 +312,12 @@ parse_args(int argc, char **argv)
 	while ((op = getopt(argc, argv, "n:r:HL:T")) != -1) {
 		switch (op) {
 		case 'n':
-			expected_ns_test = atoi(optarg);
+			val = spdk_strtol(optarg, 10);
+			if (val < 0) {
+				fprintf(stderr, "Invalid NS attribute notice ID\n");
+				return val;
+			}
+			expected_ns_test = (uint32_t)val;
 			break;
 		case 'r':
 			if (spdk_nvme_transport_id_parse(&g_trid, optarg) != 0) {
diff --git a/test/nvme/overhead/overhead.c b/test/nvme/overhead/overhead.c
index f35247a21..83c046805 100644
--- a/test/nvme/overhead/overhead.c
+++ b/test/nvme/overhead/overhead.c
@@ -545,6 +545,7 @@ static int
 parse_args(int argc, char **argv)
 {
 	int op;
+	long int val;
 
 	/* default value */
 	g_io_size_bytes = 0;
@@ -557,10 +558,19 @@ parse_args(int argc, char **argv)
 			exit(0);
 			break;
 		case 's':
-			g_io_size_bytes = atoi(optarg);
+			val = spdk_strtol(optarg, 10);
+			if (val < 0) {
+				fprintf(stderr, "Invalid io size\n");
+				return val;
+			}
+			g_io_size_bytes = (uint32_t)val;
 			break;
 		case 't':
-			g_time_in_sec = atoi(optarg);
+			g_time_in_sec = spdk_strtol(optarg, 10);
+			if (g_time_in_sec < 0) {
+				fprintf(stderr, "Invalid run time\n");
+				return g_time_in_sec;
+			}
 			break;
 		case 'H':
 			g_enable_histogram = true;
diff --git a/test/nvme/reset/reset.c b/test/nvme/reset/reset.c
index fe2004e8e..62f114034 100644
--- a/test/nvme/reset/reset.c
+++ b/test/nvme/reset/reset.c
@@ -382,6 +382,7 @@ parse_args(int argc, char **argv)
 	const char *workload_type;
 	int op;
 	bool mix_specified = false;
+	long int val;
 
 	/* default value */
 	g_queue_depth = 0;
@@ -391,26 +392,35 @@ parse_args(int argc, char **argv)
 	g_rw_percentage = -1;
 
 	while ((op = getopt(argc, argv, "m:q:s:t:w:M:")) != -1) {
-		switch (op) {
-		case 'q':
-			g_queue_depth = atoi(optarg);
-			break;
-		case 's':
-			g_io_size_bytes = atoi(optarg);
-			break;
-		case 't':
-			g_time_in_sec = atoi(optarg);
-			break;
-		case 'w':
+		if (op == 'w') {
 			workload_type = optarg;
-			break;
-		case 'M':
-			g_rw_percentage = atoi(optarg);
-			mix_specified = true;
-			break;
-		default:
+		} else if (op == '?') {
 			usage(argv[0]);
-			return 1;
+			return -EINVAL;
+		} else {
+			val = spdk_strtol(optarg, 10);
+			if (val < 0) {
+				fprintf(stderr, "Converting a string to integer failed\n");
+				return val;
+			}
+			switch (op) {
+			case 'q':
+				g_queue_depth = val;
+				break;
+			case 's':
+				g_io_size_bytes = val;
+				break;
+			case 't':
+				g_time_in_sec = val;
+				break;
+			case 'M':
+				g_rw_percentage = val;
+				mix_specified = true;
+				break;
+			default:
+				usage(argv[0]);
+				return -EINVAL;
+			}
 		}
 	}