prevent oops in generic device when port mode not correctly provided

diff --git a/palacios/src/devices/generic.c b/palacios/src/devices/generic.c
index ba2965f..bf4adc4 100644 (file)
--- a/palacios/src/devices/generic.c
+++ b/palacios/src/devices/generic.c
@@ -749,6 +749,10 @@ static int generic_init(struct v3_vm_info * vm, v3_cfg_tree_t * cfg) {
        uint16_t start = atox(v3_cfg_val(port_cfg, "start"));
        uint16_t end = atox(v3_cfg_val(port_cfg, "end"));
        char * mode_str = v3_cfg_val(port_cfg, "mode");
+    if (!mode_str) {
+        PrintError(vm, VCORE_NONE, "generic (%s): error getting port mode\n", state->name);
+        return -1;
+    }
        generic_mode_t mode = GENERIC_IGNORE;
        if (strcasecmp(mode_str, "print_and_ignore") == 0) {
            mode = GENERIC_PRINT_AND_IGNORE;