]> www.pilppa.org Git - linux-2.6-omap-h63xx.git/blobdiff - security/selinux/hooks.c
SELinux: properly handle empty tty_files list
[linux-2.6-omap-h63xx.git] / security / selinux / hooks.c
index 4a7374c12d9ca5a2b9c76c1101ecb42ee44b48af..f85597a4d733f06d89e69987cf48f02606bb2d27 100644 (file)
@@ -75,6 +75,7 @@
 #include <linux/string.h>
 #include <linux/selinux.h>
 #include <linux/mutex.h>
+#include <linux/posix-timers.h>
 
 #include "avc.h"
 #include "objsec.h"
@@ -291,6 +292,7 @@ static void sk_free_security(struct sock *sk)
        struct sk_security_struct *ssec = sk->sk_security;
 
        sk->sk_security = NULL;
+       selinux_netlbl_sk_security_free(ssec);
        kfree(ssec);
 }
 
@@ -324,7 +326,7 @@ enum {
        Opt_rootcontext = 4,
 };
 
-static match_table_t tokens = {
+static const match_table_t tokens = {
        {Opt_context, CONTEXT_STR "%s"},
        {Opt_fscontext, FSCONTEXT_STR "%s"},
        {Opt_defcontext, DEFCONTEXT_STR "%s"},
@@ -2121,26 +2123,27 @@ static inline void flush_unauthorized_files(struct files_struct *files)
        long j = -1;
        int drop_tty = 0;
 
-       mutex_lock(&tty_mutex);
        tty = get_current_tty();
        if (tty) {
                file_list_lock();
-               file = list_entry(tty->tty_files.next, typeof(*file), f_u.fu_list);
-               if (file) {
+               if (!list_empty(&tty->tty_files)) {
+                       struct inode *inode;
+
                        /* Revalidate access to controlling tty.
                           Use inode_has_perm on the tty inode directly rather
                           than using file_has_perm, as this particular open
                           file may belong to another process and we are only
                           interested in the inode-based check here. */
-                       struct inode *inode = file->f_path.dentry->d_inode;
+                       file = list_first_entry(&tty->tty_files, struct file, f_u.fu_list);
+                       inode = file->f_path.dentry->d_inode;
                        if (inode_has_perm(current, inode,
                                           FILE__READ | FILE__WRITE, NULL)) {
                                drop_tty = 1;
                        }
                }
                file_list_unlock();
+               tty_kref_put(tty);
        }
-       mutex_unlock(&tty_mutex);
        /* Reset controlling tty. */
        if (drop_tty)
                no_tty();
@@ -2322,13 +2325,7 @@ static void selinux_bprm_post_apply_creds(struct linux_binprm *bprm)
                        initrlim = init_task.signal->rlim+i;
                        rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
                }
-               if (current->signal->rlim[RLIMIT_CPU].rlim_cur != RLIM_INFINITY) {
-                       /*
-                        * This will cause RLIMIT_CPU calculations
-                        * to be refigured.
-                        */
-                       current->it_prof_expires = jiffies_to_cputime(1);
-               }
+               update_rlimit_cpu(rlim->rlim_cur);
        }
 
        /* Wake up the parent if it is waiting so that it can
@@ -3801,6 +3798,7 @@ out:
 
 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
 {
+       struct sock *sk = sock->sk;
        struct inode_security_struct *isec;
        int err;
 
@@ -3814,7 +3812,6 @@ static int selinux_socket_connect(struct socket *sock, struct sockaddr *address,
        isec = SOCK_INODE(sock)->i_security;
        if (isec->sclass == SECCLASS_TCP_SOCKET ||
            isec->sclass == SECCLASS_DCCP_SOCKET) {
-               struct sock *sk = sock->sk;
                struct avc_audit_data ad;
                struct sockaddr_in *addr4 = NULL;
                struct sockaddr_in6 *addr6 = NULL;
@@ -3848,6 +3845,8 @@ static int selinux_socket_connect(struct socket *sock, struct sockaddr *address,
                        goto out;
        }
 
+       err = selinux_netlbl_socket_connect(sk, address);
+
 out:
        return err;
 }
@@ -4077,20 +4076,28 @@ static int selinux_sock_rcv_skb_iptables_compat(struct sock *sk,
 }
 
 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
-                                      struct avc_audit_data *ad,
-                                      u16 family, char *addrp)
+                                      u16 family)
 {
        int err;
        struct sk_security_struct *sksec = sk->sk_security;
        u32 peer_sid;
        u32 sk_sid = sksec->sid;
+       struct avc_audit_data ad;
+       char *addrp;
+
+       AVC_AUDIT_DATA_INIT(&ad, NET);
+       ad.u.net.netif = skb->iif;
+       ad.u.net.family = family;
+       err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
+       if (err)
+               return err;
 
        if (selinux_compat_net)
-               err = selinux_sock_rcv_skb_iptables_compat(sk, skb, ad,
+               err = selinux_sock_rcv_skb_iptables_compat(sk, skb, &ad,
                                                           family, addrp);
        else
                err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
-                                  PACKET__RECV, ad);
+                                  PACKET__RECV, &ad);
        if (err)
                return err;
 
@@ -4099,12 +4106,14 @@ static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
                if (err)
                        return err;
                err = avc_has_perm(sk_sid, peer_sid,
-                                  SECCLASS_PEER, PEER__RECV, ad);
+                                  SECCLASS_PEER, PEER__RECV, &ad);
+               if (err)
+                       selinux_netlbl_err(skb, err, 0);
        } else {
-               err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, ad);
+               err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
                if (err)
                        return err;
-               err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, ad);
+               err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
        }
 
        return err;
@@ -4118,6 +4127,8 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
        u32 sk_sid = sksec->sid;
        struct avc_audit_data ad;
        char *addrp;
+       u8 secmark_active;
+       u8 peerlbl_active;
 
        if (family != PF_INET && family != PF_INET6)
                return 0;
@@ -4126,6 +4137,18 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
        if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
                family = PF_INET;
 
+       /* If any sort of compatibility mode is enabled then handoff processing
+        * to the selinux_sock_rcv_skb_compat() function to deal with the
+        * special handling.  We do this in an attempt to keep this function
+        * as fast and as clean as possible. */
+       if (selinux_compat_net || !selinux_policycap_netpeer)
+               return selinux_sock_rcv_skb_compat(sk, skb, family);
+
+       secmark_active = selinux_secmark_enabled();
+       peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
+       if (!secmark_active && !peerlbl_active)
+               return 0;
+
        AVC_AUDIT_DATA_INIT(&ad, NET);
        ad.u.net.netif = skb->iif;
        ad.u.net.family = family;
@@ -4133,15 +4156,7 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
        if (err)
                return err;
 
-       /* If any sort of compatibility mode is enabled then handoff processing
-        * to the selinux_sock_rcv_skb_compat() function to deal with the
-        * special handling.  We do this in an attempt to keep this function
-        * as fast and as clean as possible. */
-       if (selinux_compat_net || !selinux_policycap_netpeer)
-               return selinux_sock_rcv_skb_compat(sk, skb, &ad,
-                                                  family, addrp);
-
-       if (netlbl_enabled() || selinux_xfrm_enabled()) {
+       if (peerlbl_active) {
                u32 peer_sid;
 
                err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
@@ -4149,13 +4164,17 @@ static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
                        return err;
                err = selinux_inet_sys_rcv_skb(skb->iif, addrp, family,
                                               peer_sid, &ad);
-               if (err)
+               if (err) {
+                       selinux_netlbl_err(skb, err, 0);
                        return err;
+               }
                err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
                                   PEER__RECV, &ad);
+               if (err)
+                       selinux_netlbl_err(skb, err, 0);
        }
 
-       if (selinux_secmark_enabled()) {
+       if (secmark_active) {
                err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
                                   PACKET__RECV, &ad);
                if (err)
@@ -4214,10 +4233,12 @@ static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *
        u32 peer_secid = SECSID_NULL;
        u16 family;
 
-       if (sock)
+       if (skb && skb->protocol == htons(ETH_P_IP))
+               family = PF_INET;
+       else if (skb && skb->protocol == htons(ETH_P_IPV6))
+               family = PF_INET6;
+       else if (sock)
                family = sock->sk->sk_family;
-       else if (skb && skb->sk)
-               family = skb->sk->sk_family;
        else
                goto out;
 
@@ -4275,8 +4296,6 @@ static void selinux_sock_graft(struct sock *sk, struct socket *parent)
            sk->sk_family == PF_UNIX)
                isec->sid = sksec->sid;
        sksec->sclass = isec->sclass;
-
-       selinux_netlbl_sock_graft(sk, parent);
 }
 
 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
@@ -4284,10 +4303,15 @@ static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 {
        struct sk_security_struct *sksec = sk->sk_security;
        int err;
+       u16 family = sk->sk_family;
        u32 newsid;
        u32 peersid;
 
-       err = selinux_skb_peerlbl_sid(skb, sk->sk_family, &peersid);
+       /* handle mapped IPv4 packets arriving via IPv6 sockets */
+       if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
+               family = PF_INET;
+
+       err = selinux_skb_peerlbl_sid(skb, family, &peersid);
        if (err)
                return err;
        if (peersid == SECSID_NULL) {
@@ -4322,12 +4346,18 @@ static void selinux_inet_csk_clone(struct sock *newsk,
        selinux_netlbl_sk_security_reset(newsksec, req->rsk_ops->family);
 }
 
-static void selinux_inet_conn_established(struct sock *sk,
-                               struct sk_buff *skb)
+static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
 {
+       u16 family = sk->sk_family;
        struct sk_security_struct *sksec = sk->sk_security;
 
-       selinux_skb_peerlbl_sid(skb, sk->sk_family, &sksec->peer_sid);
+       /* handle mapped IPv4 packets arriving via IPv6 sockets */
+       if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
+               family = PF_INET;
+
+       selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
+
+       selinux_netlbl_inet_conn_established(sk, family);
 }
 
 static void selinux_req_classify_flow(const struct request_sock *req,
@@ -4377,39 +4407,54 @@ out:
 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
                                       u16 family)
 {
+       int err;
        char *addrp;
        u32 peer_sid;
        struct avc_audit_data ad;
        u8 secmark_active;
+       u8 netlbl_active;
        u8 peerlbl_active;
 
        if (!selinux_policycap_netpeer)
                return NF_ACCEPT;
 
        secmark_active = selinux_secmark_enabled();
-       peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
+       netlbl_active = netlbl_enabled();
+       peerlbl_active = netlbl_active || selinux_xfrm_enabled();
        if (!secmark_active && !peerlbl_active)
                return NF_ACCEPT;
 
+       if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
+               return NF_DROP;
+
        AVC_AUDIT_DATA_INIT(&ad, NET);
        ad.u.net.netif = ifindex;
        ad.u.net.family = family;
        if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
                return NF_DROP;
 
-       if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
-               return NF_DROP;
-
-       if (peerlbl_active)
-               if (selinux_inet_sys_rcv_skb(ifindex, addrp, family,
-                                            peer_sid, &ad) != 0)
+       if (peerlbl_active) {
+               err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
+                                              peer_sid, &ad);
+               if (err) {
+                       selinux_netlbl_err(skb, err, 1);
                        return NF_DROP;
+               }
+       }
 
        if (secmark_active)
                if (avc_has_perm(peer_sid, skb->secmark,
                                 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
                        return NF_DROP;
 
+       if (netlbl_active)
+               /* we do this in the FORWARD path and not the POST_ROUTING
+                * path because we want to make sure we apply the necessary
+                * labeling before IPsec is applied so we can leverage AH
+                * protection */
+               if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
+                       return NF_DROP;
+
        return NF_ACCEPT;
 }
 
@@ -4433,6 +4478,37 @@ static unsigned int selinux_ipv6_forward(unsigned int hooknum,
 }
 #endif /* IPV6 */
 
+static unsigned int selinux_ip_output(struct sk_buff *skb,
+                                     u16 family)
+{
+       u32 sid;
+
+       if (!netlbl_enabled())
+               return NF_ACCEPT;
+
+       /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
+        * because we want to make sure we apply the necessary labeling
+        * before IPsec is applied so we can leverage AH protection */
+       if (skb->sk) {
+               struct sk_security_struct *sksec = skb->sk->sk_security;
+               sid = sksec->sid;
+       } else
+               sid = SECINITSID_KERNEL;
+       if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
+               return NF_DROP;
+
+       return NF_ACCEPT;
+}
+
+static unsigned int selinux_ipv4_output(unsigned int hooknum,
+                                       struct sk_buff *skb,
+                                       const struct net_device *in,
+                                       const struct net_device *out,
+                                       int (*okfn)(struct sk_buff *))
+{
+       return selinux_ip_output(skb, PF_INET);
+}
+
 static int selinux_ip_postroute_iptables_compat(struct sock *sk,
                                                int ifindex,
                                                struct avc_audit_data *ad,
@@ -4500,30 +4576,36 @@ static int selinux_ip_postroute_iptables_compat(struct sock *sk,
 
 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
                                                int ifindex,
-                                               struct avc_audit_data *ad,
-                                               u16 family,
-                                               char *addrp,
-                                               u8 proto)
+                                               u16 family)
 {
        struct sock *sk = skb->sk;
        struct sk_security_struct *sksec;
+       struct avc_audit_data ad;
+       char *addrp;
+       u8 proto;
 
        if (sk == NULL)
                return NF_ACCEPT;
        sksec = sk->sk_security;
 
+       AVC_AUDIT_DATA_INIT(&ad, NET);
+       ad.u.net.netif = ifindex;
+       ad.u.net.family = family;
+       if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
+               return NF_DROP;
+
        if (selinux_compat_net) {
                if (selinux_ip_postroute_iptables_compat(skb->sk, ifindex,
-                                                        ad, family, addrp))
+                                                        &ad, family, addrp))
                        return NF_DROP;
        } else {
                if (avc_has_perm(sksec->sid, skb->secmark,
-                                SECCLASS_PACKET, PACKET__SEND, ad))
+                                SECCLASS_PACKET, PACKET__SEND, &ad))
                        return NF_DROP;
        }
 
        if (selinux_policycap_netpeer)
-               if (selinux_xfrm_postroute_last(sksec->sid, skb, ad, proto))
+               if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
                        return NF_DROP;
 
        return NF_ACCEPT;
@@ -4537,23 +4619,15 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
        struct sock *sk;
        struct avc_audit_data ad;
        char *addrp;
-       u8 proto;
        u8 secmark_active;
        u8 peerlbl_active;
 
-       AVC_AUDIT_DATA_INIT(&ad, NET);
-       ad.u.net.netif = ifindex;
-       ad.u.net.family = family;
-       if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
-               return NF_DROP;
-
        /* If any sort of compatibility mode is enabled then handoff processing
         * to the selinux_ip_postroute_compat() function to deal with the
         * special handling.  We do this in an attempt to keep this function
         * as fast and as clean as possible. */
        if (selinux_compat_net || !selinux_policycap_netpeer)
-               return selinux_ip_postroute_compat(skb, ifindex, &ad,
-                                                  family, addrp, proto);
+               return selinux_ip_postroute_compat(skb, ifindex, family);
 
        /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
         * packet transformation so allow the packet to pass without any checks
@@ -4569,21 +4643,45 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
        if (!secmark_active && !peerlbl_active)
                return NF_ACCEPT;
 
-       /* if the packet is locally generated (skb->sk != NULL) then use the
-        * socket's label as the peer label, otherwise the packet is being
-        * forwarded through this system and we need to fetch the peer label
-        * directly from the packet */
+       /* if the packet is being forwarded then get the peer label from the
+        * packet itself; otherwise check to see if it is from a local
+        * application or the kernel, if from an application get the peer label
+        * from the sending socket, otherwise use the kernel's sid */
        sk = skb->sk;
-       if (sk) {
+       if (sk == NULL) {
+               switch (family) {
+               case PF_INET:
+                       if (IPCB(skb)->flags & IPSKB_FORWARDED)
+                               secmark_perm = PACKET__FORWARD_OUT;
+                       else
+                               secmark_perm = PACKET__SEND;
+                       break;
+               case PF_INET6:
+                       if (IP6CB(skb)->flags & IP6SKB_FORWARDED)
+                               secmark_perm = PACKET__FORWARD_OUT;
+                       else
+                               secmark_perm = PACKET__SEND;
+                       break;
+               default:
+                       return NF_DROP;
+               }
+               if (secmark_perm == PACKET__FORWARD_OUT) {
+                       if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
+                               return NF_DROP;
+               } else
+                       peer_sid = SECINITSID_KERNEL;
+       } else {
                struct sk_security_struct *sksec = sk->sk_security;
                peer_sid = sksec->sid;
                secmark_perm = PACKET__SEND;
-       } else {
-               if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
-                               return NF_DROP;
-               secmark_perm = PACKET__FORWARD_OUT;
        }
 
+       AVC_AUDIT_DATA_INIT(&ad, NET);
+       ad.u.net.netif = ifindex;
+       ad.u.net.family = family;
+       if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
+               return NF_DROP;
+
        if (secmark_active)
                if (avc_has_perm(peer_sid, skb->secmark,
                                 SECCLASS_PACKET, secmark_perm, &ad))
@@ -5657,6 +5755,13 @@ static struct nf_hook_ops selinux_ipv4_ops[] = {
                .pf =           PF_INET,
                .hooknum =      NF_INET_FORWARD,
                .priority =     NF_IP_PRI_SELINUX_FIRST,
+       },
+       {
+               .hook =         selinux_ipv4_output,
+               .owner =        THIS_MODULE,
+               .pf =           PF_INET,
+               .hooknum =      NF_INET_LOCAL_OUT,
+               .priority =     NF_IP_PRI_SELINUX_FIRST,
        }
 };