diff --git a/sys/dev/bnxt/bnxt_en/bnxt_sysctl.c b/sys/dev/bnxt/bnxt_en/bnxt_sysctl.c
--- a/sys/dev/bnxt/bnxt_en/bnxt_sysctl.c
+++ b/sys/dev/bnxt/bnxt_en/bnxt_sysctl.c
@@ -1886,24 +1886,24 @@
 }
 
 static void
-bnxt_app_tlv_get_string(struct bnxt_softc *softc, char *buf,
+bnxt_app_tlv_get_string(struct bnxt_softc *softc, struct sbuf *sb,
 			struct bnxt_dcb_app *app, int num)
 {
-	uint32_t i;
+	int i;
 
-	if (!num) {
-		buf += sprintf(buf, " None");
+	if (num == 0) {
+		sbuf_printf(sb, " None");
 		return;
 	}
 
-	buf += sprintf(buf, "\n");
+	sbuf_putc(sb, '\n');
 	for (i = 0; i < num; i++) {
-		buf += sprintf(buf, "\tAPP#%0d:\tpri: %d,\tSel: %d,\t%s: %d\n",
-				i,
-				app[i].priority,
-				app[i].selector,
-				bnxt_get_tlv_selector_str(app[i].selector),
-				app[i].protocol);
+		sbuf_printf(sb, "\tAPP#%0d:\tpri: %d,\tSel: %d,\t%s: %d\n",
+		    i,
+		    app[i].priority,
+		    app[i].selector,
+		    bnxt_get_tlv_selector_str(app[i].selector),
+		    app[i].protocol);
 	}
 }
 
@@ -1936,25 +1936,20 @@
 static int
 bnxt_dcb_list_app(SYSCTL_HANDLER_ARGS)
 {
+	struct sbuf sb;
 	struct bnxt_dcb_app app[128] = {0};
 	struct bnxt_softc *softc = arg1;
 	int rc, num_inputs = 0;
-	char *buf;
 
-#define BNXT_APP_TLV_STR_LEN	4096
-	buf = malloc(BNXT_APP_TLV_STR_LEN, M_DEVBUF, M_NOWAIT | M_ZERO);
-	if (!buf)
+	if (sbuf_new(&sb, NULL, 4096, SBUF_NOWAIT | SBUF_FIXEDLEN) == NULL)
 		return ENOMEM;
 
 	bnxt_dcb_ieee_listapp(softc, app, &num_inputs);
-	bnxt_app_tlv_get_string(softc, buf, app, num_inputs);
-
-	rc = sysctl_handle_string(oidp, buf, BNXT_APP_TLV_STR_LEN, req);
-	if (rc || req->newptr == NULL)
-		goto end;
+	bnxt_app_tlv_get_string(softc, &sb, app, num_inputs);
 
-end:
-	free(buf, M_DEVBUF);
+	sbuf_finish(&sb);
+	rc = sysctl_handle_string(oidp, sbuf_data(&sb), sbuf_len(&sb), req);
+	sbuf_delete(&sb);
 	return rc;
 }