dma/idxd: verify strdup return

[ upstream commit 83cfa2cbf3f3fb78e2f2dd228109adcb38e18a5c ]

Add verify strdup return value logic.

Fixes: e888bb1 ("dma/idxd: add bus device probing")

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>

drivers/dma/idxd/idxd_bus.c

@@ -248,9 +248,15 @@ static int
 is_for_this_process_use(const char *name)
 {
 	char *runtime_dir = strdup(rte_eal_get_runtime_dir());
-	char *prefix = basename(runtime_dir);
-	int prefixlen = strlen(prefix);
 	int retval = 0;
+	int prefixlen;
+	char *prefix;
+
+	if (runtime_dir == NULL)
+		return retval;
+
+	prefix = basename(runtime_dir);
+	prefixlen = strlen(prefix);
 
 	if (strncmp(name, "dpdk_", 5) == 0)
 		retval = 1;