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>

2 files changed, 13 insertions, 8 deletions

diff --git a/arch/alpha/kernel/asm-offsets.c b/arch/alpha/kernel/asm-offsets.c
index 4b18cd94d59d..6ff8886e7e22 100644
--- a/arch/alpha/kernel/asm-offsets.c
+++ b/arch/alpha/kernel/asm-offsets.c
@@ -19,15 +19,18 @@ void foo(void)
         BLANK();
 
         DEFINE(TASK_BLOCKED, offsetof(struct task_struct, blocked));
-        DEFINE(TASK_UID, offsetof(struct task_struct, uid));
-        DEFINE(TASK_EUID, offsetof(struct task_struct, euid));
-        DEFINE(TASK_GID, offsetof(struct task_struct, gid));
-        DEFINE(TASK_EGID, offsetof(struct task_struct, egid));
+        DEFINE(TASK_CRED, offsetof(struct task_struct, cred));
         DEFINE(TASK_REAL_PARENT, offsetof(struct task_struct, real_parent));
         DEFINE(TASK_GROUP_LEADER, offsetof(struct task_struct, group_leader));
         DEFINE(TASK_TGID, offsetof(struct task_struct, tgid));
         BLANK();
 
+        DEFINE(CRED_UID,  offsetof(struct cred, uid));
+        DEFINE(CRED_EUID, offsetof(struct cred, euid));
+        DEFINE(CRED_GID,  offsetof(struct cred, gid));
+        DEFINE(CRED_EGID, offsetof(struct cred, egid));
+        BLANK();
+
         DEFINE(SIZEOF_PT_REGS, sizeof(struct pt_regs));
         DEFINE(PT_PTRACED, PT_PTRACED);
         DEFINE(CLONE_VM, CLONE_VM);
diff --git a/arch/alpha/kernel/entry.S b/arch/alpha/kernel/entry.S
index 5fc61e281ac7..f77345bc66a9 100644
--- a/arch/alpha/kernel/entry.S
+++ b/arch/alpha/kernel/entry.S
@@ -850,8 +850,9 @@ osf_getpriority:
 sys_getxuid:
         .prologue 0
         ldq     $2, TI_TASK($8)
-        ldl     $0, TASK_UID($2)
-        ldl     $1, TASK_EUID($2)
+        ldq     $3, TASK_CRED($2)
+        ldl     $0, CRED_UID($3)
+        ldl     $1, CRED_EUID($3)
         stq     $1, 80($sp)
         ret
 .end sys_getxuid
@@ -862,8 +863,9 @@ sys_getxuid:
 sys_getxgid:
         .prologue 0
         ldq     $2, TI_TASK($8)
-        ldl     $0, TASK_GID($2)
-        ldl     $1, TASK_EGID($2)
+        ldq     $3, TASK_CRED($2)
+        ldl     $0, CRED_GID($3)
+        ldl     $1, CRED_EGID($3)
         stq     $1, 80($sp)
         ret
 .end sys_getxgid