Smack: Fix the issue of permission denied error in ipv6 hook

Permission denied error comes when 2 IPv6 servers are running and client
tries to connect one of them. Scenario is that both servers are using same
IP and port but different protocols(Udp and tcp). They are using different
SMACK64IPIN labels.Tcp server is using "test" and udp server is using
"test-in". When we try to run tcp client with SMACK64IPOUT label as "test",
then connection denied error comes. It should not happen since both tcp
server and client labels are same.This happens because there is no check
for protocol in smk_ipv6_port_label() function while searching for the
earlier port entry. It checks whether there is an existing port entry on
the basis of port only. So it updates the earlier port entry in the list.
Due to which smack label gets changed for earlier entry in the
"smk_ipv6_port_list" list and permission denied error comes.

Now a check is added for socket type also.Now if 2 processes use same
port  but different protocols (tcp or udp), then 2 different port entries
will be  added in the list. Similarly while checking smack access in
smk_ipv6_port_check() function,  port entry is searched on the basis of
both port and protocol.

Signed-off-by: Vishal Goel <vishal.goel@samsung.com>
Signed-off-by: Himanshu Shukla <Himanshu.sh@samsung.com>
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>

diff --git a/security/smack/smack.h b/security/smack/smack.h
index 77abe2efacae47f121c348c74801a0c0831fc793..73480ee0747864d39e171f0e33b163ae3c084f55 100644 (file)
--- a/security/smack/smack.h
+++ b/security/smack/smack.h
@@ -173,6 +173,7 @@ struct smk_port_label {
        unsigned short          smk_port;       /* the port number */
        struct smack_known      *smk_in;        /* inbound label */
        struct smack_known      *smk_out;       /* outgoing label */
+       short                   smk_sock_type;  /* Socket type */
 };
 #endif /* SMACK_IPV6_PORT_LABELING */
 

diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index b76696b84e5ced2f810d1ed381e4fd473aca370e..5e4d2bdb38cbbb1a81dbef8fad8572a656149894 100644 (file)
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -2635,7 +2635,7 @@ static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
         */
        rcu_read_lock();
        list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
-               if (spp->smk_port != port)
+               if (spp->smk_port != port || spp->smk_sock_type != sock->type)
                        continue;
                spp->smk_port = port;
                spp->smk_sock = sk;
@@ -2656,6 +2656,7 @@ static void smk_ipv6_port_label(struct socket *sock, struct sockaddr *address)
        spp->smk_sock = sk;
        spp->smk_in = ssp->smk_in;
        spp->smk_out = ssp->smk_out;
+       spp->smk_sock_type = sock->type;
 
        mutex_lock(&smack_ipv6_lock);
        list_add_rcu(&spp->list, &smk_ipv6_port_list);
@@ -2712,7 +2713,7 @@ static int smk_ipv6_port_check(struct sock *sk, struct sockaddr_in6 *address,
        port = ntohs(address->sin6_port);
        rcu_read_lock();
        list_for_each_entry_rcu(spp, &smk_ipv6_port_list, list) {
-               if (spp->smk_port != port)
+               if (spp->smk_port != port || spp->smk_sock_type != sk->sk_type)
                        continue;
                object = spp->smk_in;
                if (act == SMK_CONNECTING)