Issue 3: Fix double skb allocation

Also fill msg only after skb allocation succeed
wangrong1069 · Feb 2, 2019 · f3c564e · f3c564e
1 parent 3756ed4
commit f3c564e
Showing 1 changed file with 3 additions and 4 deletions.
diff --git a/kernel/genl_ex.c b/kernel/genl_ex.c
@@ -19,10 +19,6 @@ static void greet_group(unsigned int group)
 	char msg[GENL_TEST_ATTR_MSG_MAX];
 	struct sk_buff* skb = genlmsg_new(NLMSG_DEFAULT_SIZE, flags);
 
-	snprintf(msg, GENL_TEST_ATTR_MSG_MAX, "Hello group %s\n", 
-			genl_test_mcgrp_names[group]);
-	skb = genlmsg_new(NLMSG_DEFAULT_SIZE, flags);
-
 	if (!skb) {
 		printk(KERN_ERR "%d: OOM!!", __LINE__);
 		return;
@@ -34,6 +30,9 @@ static void greet_group(unsigned int group)
 		goto nlmsg_fail;
 	}
 
+	snprintf(msg, GENL_TEST_ATTR_MSG_MAX, "Hello group %s\n",
+			genl_test_mcgrp_names[group]);
+
 	res = nla_put_string(skb, GENL_TEST_ATTR_MSG, msg);
 	if (res) {
 		printk(KERN_ERR "%d: err %d ", __LINE__, res);