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: bd60efd10145 ("net/ncsi: Add generic netlink family")
Signed-off-by: Jiasheng Jiang <jiasheng@iscas.ac.cn>
Link: https://lore.kernel.org/r/20211229032118.1706294-1-jiasheng@iscas.ac.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ncsi/ncsi-netlink.c b/net/ncsi/ncsi-netlink.c
index bb5f1650f11cb3a5e1c2c714603ab3468a759992..c189b4c8a1823e328367c2c98ff9caf5be69286b 100644 (file)
--- a/net/ncsi/ncsi-netlink.c
+++ b/net/ncsi/ncsi-netlink.c
@@ -112,7 +112,11 @@ static int ncsi_write_package_info(struct sk_buff *skb,
                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);