net/ncsi: check for error return from call to nla_put_u32

As we can see from the comment of the nla_put() that it could return
-EMSGSIZE if the tailroom of the skb is insufficient.
Therefore, it should be better to check the return value of the
nla_put_u32 and return the error code if error accurs.
Also, there are many other functions have the same problem, and if this
patch is correct, I will commit a new version to fix all.

Fixes: 955dc68cb9b2 ("net/ncsi: Add generic netlink family")
Signed-off-by: Jiasheng Jiang <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Jakub Kicinski <[e-mail]>

net/ncsi/ncsi-netlink.c

···
 		pnest = nla_nest_start_noflag(skb, NCSI_PKG_ATTR);
 		if (!pnest)
 			return -ENOMEM;
-		nla_put_u32(skb, NCSI_PKG_ATTR_ID, np->id);
+		rc = nla_put_u32(skb, NCSI_PKG_ATTR_ID, np->id);
+		if (rc) {
+			nla_nest_cancel(skb, pnest);
+			return rc;
+		}
 		if ((0x1 << np->id) == ndp->package_whitelist)
 			nla_put_flag(skb, NCSI_PKG_ATTR_FORCED);
 		cnest = nla_nest_start_noflag(skb, NCSI_PKG_ATTR_CHANNEL_LIST);