CRED: Separate task security context from task_struct

Separate the task security context from task_struct.  At this point, the
security data is temporarily embedded in the task_struct with two pointers
pointing to it.

Note that the Alpha arch is altered as it refers to (E)UID and (E)GID in
entry.S via asm-offsets.

With comment fixes Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Signed-off-by: James Morris <jmorris@namei.org>

3 files changed, 45 insertions, 42 deletions

diff --git a/security/smack/smack_access.c b/security/smack/smack_access.c
index 79ff21ed4c3b..b6dd4fc0fb0b 100644
--- a/security/smack/smack_access.c
+++ b/security/smack/smack_access.c
@@ -164,7 +164,7 @@ int smk_curacc(char *obj_label, u32 mode)
 {
         int rc;
 
-        rc = smk_access(current->security, obj_label, mode);
+        rc = smk_access(current->cred->security, obj_label, mode);
         if (rc == 0)
                 return 0;
 
@@ -173,7 +173,7 @@ int smk_curacc(char *obj_label, u32 mode)
          * only one that gets privilege and current does not
          * have that label.
          */
-        if (smack_onlycap != NULL && smack_onlycap != current->security)
+        if (smack_onlycap != NULL && smack_onlycap != current->cred->security)
                 return rc;
 
         if (capable(CAP_MAC_OVERRIDE))
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 6e2dc0bab70d..791da238d049 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -102,7 +102,8 @@ static int smack_ptrace_may_access(struct task_struct *ctp, unsigned int mode)
         if (rc != 0)
                 return rc;
 
-        rc = smk_access(current->security, ctp->security, MAY_READWRITE);
+        rc = smk_access(current->cred->security, ctp->cred->security,
+                        MAY_READWRITE);
         if (rc != 0 && capable(CAP_MAC_OVERRIDE))
                 return 0;
         return rc;
@@ -124,7 +125,8 @@ static int smack_ptrace_traceme(struct task_struct *ptp)
         if (rc != 0)
                 return rc;
 
-        rc = smk_access(ptp->security, current->security, MAY_READWRITE);
+        rc = smk_access(ptp->cred->security, current->cred->security,
+                        MAY_READWRITE);
         if (rc != 0 && has_capability(ptp, CAP_MAC_OVERRIDE))
                 return 0;
         return rc;
@@ -141,7 +143,7 @@ static int smack_ptrace_traceme(struct task_struct *ptp)
 static int smack_syslog(int type)
 {
         int rc;
-        char *sp = current->security;
+        char *sp = current->cred->security;
 
         rc = cap_syslog(type);
         if (rc != 0)
@@ -373,7 +375,7 @@ static int smack_sb_umount(struct vfsmount *mnt, int flags)
  */
 static int smack_inode_alloc_security(struct inode *inode)
 {
-        inode->i_security = new_inode_smack(current->security);
+        inode->i_security = new_inode_smack(current->cred->security);
         if (inode->i_security == NULL)
                 return -ENOMEM;
         return 0;
@@ -818,7 +820,7 @@ static int smack_file_permission(struct file *file, int mask)
  */
 static int smack_file_alloc_security(struct file *file)
 {
-        file->f_security = current->security;
+        file->f_security = current->cred->security;
         return 0;
 }
 
@@ -916,7 +918,7 @@ static int smack_file_fcntl(struct file *file, unsigned int cmd,
  */
 static int smack_file_set_fowner(struct file *file)
 {
-        file->f_security = current->security;
+        file->f_security = current->cred->security;
         return 0;
 }
 
@@ -941,7 +943,7 @@ static int smack_file_send_sigiotask(struct task_struct *tsk,
          * struct fown_struct is never outside the context of a struct file
          */
         file = container_of(fown, struct file, f_owner);
-        rc = smk_access(file->f_security, tsk->security, MAY_WRITE);
+        rc = smk_access(file->f_security, tsk->cred->security, MAY_WRITE);
         if (rc != 0 && has_capability(tsk, CAP_MAC_OVERRIDE))
                 return 0;
         return rc;
@@ -984,7 +986,7 @@ static int smack_file_receive(struct file *file)
  */
 static int smack_task_alloc_security(struct task_struct *tsk)
 {
-        tsk->security = current->security;
+        tsk->cred->security = current->cred->security;
 
         return 0;
 }
@@ -999,7 +1001,7 @@ static int smack_task_alloc_security(struct task_struct *tsk)
  */
 static void smack_task_free_security(struct task_struct *task)
 {
-        task->security = NULL;
+        task->cred->security = NULL;
 }
 
 /**
@@ -1011,7 +1013,7 @@ static void smack_task_free_security(struct task_struct *task)
  */
 static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
 {
-        return smk_curacc(p->security, MAY_WRITE);
+        return smk_curacc(p->cred->security, MAY_WRITE);
 }
 
 /**
@@ -1022,7 +1024,7 @@ static int smack_task_setpgid(struct task_struct *p, pid_t pgid)
  */
 static int smack_task_getpgid(struct task_struct *p)
 {
-        return smk_curacc(p->security, MAY_READ);
+        return smk_curacc(p->cred->security, MAY_READ);
 }
 
 /**
@@ -1033,7 +1035,7 @@ static int smack_task_getpgid(struct task_struct *p)
  */
 static int smack_task_getsid(struct task_struct *p)
 {
-        return smk_curacc(p->security, MAY_READ);
+        return smk_curacc(p->cred->security, MAY_READ);
 }
 
 /**
@@ -1045,7 +1047,7 @@ static int smack_task_getsid(struct task_struct *p)
  */
 static void smack_task_getsecid(struct task_struct *p, u32 *secid)
 {
-        *secid = smack_to_secid(p->security);
+        *secid = smack_to_secid(p->cred->security);
 }
 
 /**
@@ -1061,7 +1063,7 @@ static int smack_task_setnice(struct task_struct *p, int nice)
 
         rc = cap_task_setnice(p, nice);
         if (rc == 0)
-                rc = smk_curacc(p->security, MAY_WRITE);
+                rc = smk_curacc(p->cred->security, MAY_WRITE);
         return rc;
 }
 
@@ -1078,7 +1080,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio)
 
         rc = cap_task_setioprio(p, ioprio);
         if (rc == 0)
-                rc = smk_curacc(p->security, MAY_WRITE);
+                rc = smk_curacc(p->cred->security, MAY_WRITE);
         return rc;
 }
 
@@ -1090,7 +1092,7 @@ static int smack_task_setioprio(struct task_struct *p, int ioprio)
  */
 static int smack_task_getioprio(struct task_struct *p)
 {
-        return smk_curacc(p->security, MAY_READ);
+        return smk_curacc(p->cred->security, MAY_READ);
 }
 
 /**
@@ -1108,7 +1110,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy,
 
         rc = cap_task_setscheduler(p, policy, lp);
         if (rc == 0)
-                rc = smk_curacc(p->security, MAY_WRITE);
+                rc = smk_curacc(p->cred->security, MAY_WRITE);
         return rc;
 }
 
@@ -1120,7 +1122,7 @@ static int smack_task_setscheduler(struct task_struct *p, int policy,
  */
 static int smack_task_getscheduler(struct task_struct *p)
 {
-        return smk_curacc(p->security, MAY_READ);
+        return smk_curacc(p->cred->security, MAY_READ);
 }
 
 /**
@@ -1131,7 +1133,7 @@ static int smack_task_getscheduler(struct task_struct *p)
  */
 static int smack_task_movememory(struct task_struct *p)
 {
-        return smk_curacc(p->security, MAY_WRITE);
+        return smk_curacc(p->cred->security, MAY_WRITE);
 }
 
 /**
@@ -1154,13 +1156,13 @@ static int smack_task_kill(struct task_struct *p, struct siginfo *info,
          * can write the receiver.
          */
         if (secid == 0)
-                return smk_curacc(p->security, MAY_WRITE);
+                return smk_curacc(p->cred->security, MAY_WRITE);
         /*
          * If the secid isn't 0 we're dealing with some USB IO
          * specific behavior. This is not clean. For one thing
          * we can't take privilege into account.
          */
-        return smk_access(smack_from_secid(secid), p->security, MAY_WRITE);
+        return smk_access(smack_from_secid(secid), p->cred->security, MAY_WRITE);
 }
 
 /**
@@ -1173,7 +1175,7 @@ static int smack_task_wait(struct task_struct *p)
 {
         int rc;
 
-        rc = smk_access(current->security, p->security, MAY_WRITE);
+        rc = smk_access(current->cred->security, p->cred->security, MAY_WRITE);
         if (rc == 0)
                 return 0;
 
@@ -1204,7 +1206,7 @@ static int smack_task_wait(struct task_struct *p)
 static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
 {
         struct inode_smack *isp = inode->i_security;
-        isp->smk_inode = p->security;
+        isp->smk_inode = p->cred->security;
 }
 
 /*
@@ -1223,7 +1225,7 @@ static void smack_task_to_inode(struct task_struct *p, struct inode *inode)
  */
 static int smack_sk_alloc_security(struct sock *sk, int family, gfp_t gfp_flags)
 {
-        char *csp = current->security;
+        char *csp = current->cred->security;
         struct socket_smack *ssp;
 
         ssp = kzalloc(sizeof(struct socket_smack), gfp_flags);
@@ -1448,7 +1450,7 @@ static int smack_flags_to_may(int flags)
  */
 static int smack_msg_msg_alloc_security(struct msg_msg *msg)
 {
-        msg->security = current->security;
+        msg->security = current->cred->security;
         return 0;
 }
 
@@ -1484,7 +1486,7 @@ static int smack_shm_alloc_security(struct shmid_kernel *shp)
 {
         struct kern_ipc_perm *isp = &shp->shm_perm;
 
-        isp->security = current->security;
+        isp->security = current->cred->security;
         return 0;
 }
 
@@ -1593,7 +1595,7 @@ static int smack_sem_alloc_security(struct sem_array *sma)
 {
         struct kern_ipc_perm *isp = &sma->sem_perm;
 
-        isp->security = current->security;
+        isp->security = current->cred->security;
         return 0;
 }
 
@@ -1697,7 +1699,7 @@ static int smack_msg_queue_alloc_security(struct msg_queue *msq)
 {
         struct kern_ipc_perm *kisp = &msq->q_perm;
 
-        kisp->security = current->security;
+        kisp->security = current->cred->security;
         return 0;
 }
 
@@ -1852,7 +1854,7 @@ static void smack_d_instantiate(struct dentry *opt_dentry, struct inode *inode)
         struct super_block *sbp;
         struct superblock_smack *sbsp;
         struct inode_smack *isp;
-        char *csp = current->security;
+        char *csp = current->cred->security;
         char *fetched;
         char *final;
         struct dentry *dp;
@@ -2009,7 +2011,7 @@ static int smack_getprocattr(struct task_struct *p, char *name, char **value)
         if (strcmp(name, "current") != 0)
                 return -EINVAL;
 
-        cp = kstrdup(p->security, GFP_KERNEL);
+        cp = kstrdup(p->cred->security, GFP_KERNEL);
         if (cp == NULL)
                 return -ENOMEM;
 
@@ -2055,7 +2057,7 @@ static int smack_setprocattr(struct task_struct *p, char *name,
         if (newsmack == NULL)
                 return -EINVAL;
 
-        p->security = newsmack;
+        p->cred->security = newsmack;
         return size;
 }
 
@@ -2288,8 +2290,8 @@ static void smack_sock_graft(struct sock *sk, struct socket *parent)
                 return;
 
         ssp = sk->sk_security;
-        ssp->smk_in = current->security;
-        ssp->smk_out = current->security;
+        ssp->smk_in = current->cred->security;
+        ssp->smk_out = current->cred->security;
         ssp->smk_packet[0] = '\0';
 
         rc = smack_netlabel(sk);
@@ -2362,7 +2364,7 @@ static int smack_inet_conn_request(struct sock *sk, struct sk_buff *skb,
 static int smack_key_alloc(struct key *key, struct task_struct *tsk,
                            unsigned long flags)
 {
-        key->security = tsk->security;
+        key->security = tsk->cred->security;
         return 0;
 }
 
@@ -2403,10 +2405,11 @@ static int smack_key_permission(key_ref_t key_ref,
         /*
          * This should not occur
          */
-        if (context->security == NULL)
+        if (context->cred->security == NULL)
                 return -EACCES;
 
-        return smk_access(context->security, keyp->security, MAY_READWRITE);
+        return smk_access(context->cred->security, keyp->security,
+                          MAY_READWRITE);
 }
 #endif /* CONFIG_KEYS */
 
@@ -2726,7 +2729,7 @@ static __init int smack_init(void)
         /*
          * Set the security state for the initial task.
          */
-        current->security = &smack_known_floor.smk_known;
+        current->cred->security = &smack_known_floor.smk_known;
 
         /*
          * Initialize locks
diff --git a/security/smack/smackfs.c b/security/smack/smackfs.c
index c21d8c8bf0c7..c5ca279e0506 100644
--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -336,7 +336,7 @@ static void smk_cipso_doi(void)
 
         audit_info.loginuid = audit_get_loginuid(current);
         audit_info.sessionid = audit_get_sessionid(current);
-        audit_info.secid = smack_to_secid(current->security);
+        audit_info.secid = smack_to_secid(current->cred->security);
 
         rc = netlbl_cfg_map_del(NULL, &audit_info);
         if (rc != 0)
@@ -371,7 +371,7 @@ static void smk_unlbl_ambient(char *oldambient)
 
         audit_info.loginuid = audit_get_loginuid(current);
         audit_info.sessionid = audit_get_sessionid(current);
-        audit_info.secid = smack_to_secid(current->security);
+        audit_info.secid = smack_to_secid(current->cred->security);
 
         if (oldambient != NULL) {
                 rc = netlbl_cfg_map_del(oldambient, &audit_info);
@@ -843,7 +843,7 @@ static ssize_t smk_write_onlycap(struct file *file, const char __user *buf,
                                  size_t count, loff_t *ppos)
 {
         char in[SMK_LABELLEN];
-        char *sp = current->security;
+        char *sp = current->cred->security;
 
         if (!capable(CAP_MAC_ADMIN))
                 return -EPERM;