Subject: [PATCH BUGFIX 25-rc1] Smack: Don't fail against Nulled sk sockets

From: "Ahmed S. Darwish" <[email-masked]>
Date: Wed, 13 Feb 2008 03:25:23 +0200

Hi!,

Appropriately handle sockets with sk = NULL. This is usually the socket
case when starting kernel nfsd.

Signed-off-by: Ahmed S. Darwish <[email-masked]>
Acked-by: Casey Schaufler <[email-masked]>
Tested-by: Joerg Platte <[email-masked]>
--

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 1c11e42..eb04278 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -701,7 +701,7 @@ static int smack_inode_getsecurity(const struct inode *inode,
 		return -EOPNOTSUPP;
 
 	sock = SOCKET_I(ip);
-	if (sock == NULL)
+	if (sock == NULL || sock->sk == NULL)
 		return -EOPNOTSUPP;
 
 	ssp = sock->sk->sk_security;
@@ -1280,10 +1280,12 @@ static void smack_to_secattr(char *smack, struct netlbl_lsm_secattr *nlsp)
  */
 static int smack_netlabel(struct sock *sk)
 {
-	struct socket_smack *ssp = sk->sk_security;
+	struct socket_smack *ssp;
 	struct netlbl_lsm_secattr secattr;
 	int rc = 0;
 
+	BUG_ON(sk == NULL);
+	ssp = sk->sk_security;
 	netlbl_secattr_init(&secattr);
 	smack_to_secattr(ssp->smk_out, &secattr);
 	if (secattr.flags != NETLBL_SECATTR_NONE)
@@ -1331,7 +1333,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name,
 		return -EOPNOTSUPP;
 
 	sock = SOCKET_I(inode);
-	if (sock == NULL)
+	if (sock == NULL || sock->sk == NULL)
 		return -EOPNOTSUPP;
 
 	ssp = sock->sk->sk_security;
@@ -1362,7 +1364,7 @@ static int smack_inode_setsecurity(struct inode *inode, const char *name,
 static int smack_socket_post_create(struct socket *sock, int family,
 				    int type, int protocol, int kern)
 {
-	if (family != PF_INET)
+	if (family != PF_INET || sock->sk == NULL)
 		return 0;
 	/*
 	 * Set the outbound netlbl.

Warm regards

-- 
Ahmed S. Darwish
Homepage: http://darwish.07.googlepages.com
Blog: http://darwish-07.blogspot.com