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>

1 files changed, 5 insertions, 5 deletions

diff --git a/mm/mempolicy.c b/mm/mempolicy.c
index 07a96474077d..b23492ee3e50 100644
--- a/mm/mempolicy.c
+++ b/mm/mempolicy.c
@@ -1110,12 +1110,12 @@ asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
                 const unsigned long __user *old_nodes,
                 const unsigned long __user *new_nodes)
 {
+        struct cred *cred, *tcred;
         struct mm_struct *mm;
         struct task_struct *task;
         nodemask_t old;
         nodemask_t new;
         nodemask_t task_nodes;
-        uid_t uid, euid;
         int err;
 
         err = get_nodes(&old, old_nodes, maxnode);
@@ -1145,10 +1145,10 @@ asmlinkage long sys_migrate_pages(pid_t pid, unsigned long maxnode,
          * capabilities, superuser privileges or the same
          * userid as the target process.
          */
-        uid = current_uid();
-        euid = current_euid();
-        if (euid != task->suid && euid != task->uid &&
-            uid  != task->suid && uid  != task->uid &&
+        cred = current->cred;
+        tcred = task->cred;
+        if (cred->euid != tcred->suid && cred->euid != tcred->uid &&
+            cred->uid  != tcred->suid && cred->uid  != tcred->uid &&
             !capable(CAP_SYS_NICE)) {
                 err = -EPERM;
                 goto out;