Re: Problem compiling nftables kernel

[Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx>]

On Thu, Sep 19, 2013 at 11:28:31AM +0200, Bjørnar Ness wrote:
> git: 6b92ef23eb12021c5ffe3ff03f60f6e0359c02c2
> 
> x86_64
> 
> net/netfilter/nft_meta.c: In function ‘nft_meta_eval’:
> net/netfilter/nft_meta.c:82:17: error: incompatible types when
> assigning to type ‘u32’ from type ‘kuid_t’
> net/netfilter/nft_meta.c:88:17: error: incompatible types when
> assigning to type ‘u32’ from type ‘kgid_t’

Please, give a try to the attached patch.

Thanks.

diff --git a/net/netfilter/nft_meta.c b/net/netfilter/nft_meta.c
index 84256bc..4c6998d 100644
--- a/net/netfilter/nft_meta.c
+++ b/net/netfilter/nft_meta.c
@@ -16,6 +16,7 @@
 #include <linux/netfilter/nf_tables.h>
 #include <net/dst.h>
 #include <net/sock.h>
+#include <net/tcp_states.h> /* for TCP_TIME_WAIT */
 #include <net/netfilter/nf_tables.h>
 
 struct nft_meta {
@@ -76,16 +77,35 @@ static void nft_meta_eval(const struct nft_expr *expr,
 		*(u16 *)dest->data = out->type;
 		break;
 	case NFT_META_SKUID:
-		if (skb->sk == NULL || skb->sk->sk_socket == NULL ||
-		    skb->sk->sk_socket->file == NULL)
+		if (skb->sk == NULL || skb->sk->sk_state == TCP_TIME_WAIT)
 			goto err;
-		dest->data[0] = skb->sk->sk_socket->file->f_cred->fsuid;
+
+		read_lock_bh(&skb->sk->sk_callback_lock);
+		if (skb->sk->sk_socket == NULL ||
+		    skb->sk->sk_socket->file == NULL) {
+			read_unlock_bh(&skb->sk->sk_callback_lock);
+			goto err;
+		}
+
+		dest->data[0] =
+			from_kuid_munged(&init_user_ns,
+				skb->sk->sk_socket->file->f_cred->fsuid);
+		read_unlock_bh(&skb->sk->sk_callback_lock);
 		break;
 	case NFT_META_SKGID:
-		if (skb->sk == NULL || skb->sk->sk_socket == NULL ||
-		    skb->sk->sk_socket->file == NULL)
+		if (skb->sk == NULL || skb->sk->sk_state == TCP_TIME_WAIT)
+			goto err;
+
+		read_lock_bh(&skb->sk->sk_callback_lock);
+		if (skb->sk->sk_socket == NULL ||
+		    skb->sk->sk_socket->file == NULL) {
+			read_unlock_bh(&skb->sk->sk_callback_lock);
 			goto err;
-		dest->data[0] = skb->sk->sk_socket->file->f_cred->fsgid;
+		}
+		dest->data[0] =
+			from_kuid_munged(&init_user_ns,
+				 skb->sk->sk_socket->file->f_cred->fsgid);
+		read_unlock_bh(&skb->sk->sk_callback_lock);
 		break;
 #ifdef CONFIG_NET_CLS_ROUTE
 	case NFT_META_RTCLASSID: {