CRED: Wrap task credential accesses in the filesystem subsystem

Wrap access to task credentials so that they can be separated more easily from
the task_struct during the introduction of COW creds.

Change most current->(|e|s|fs)[ug]id to current_(|e|s|fs)[ug]id().

Change some task->e?[ug]id to task_e?[ug]id().  In some places it makes more
sense to use RCU directly rather than a convenient wrapper; these will be
addressed by later patches.

Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <jmorris@namei.org>
Acked-by: Serge Hallyn <serue@us.ibm.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 2 insertions, 2 deletions

diff --git a/fs/attr.c b/fs/attr.c
index 7a83819f6ba2..f4360192a938 100644
--- a/fs/attr.c
+++ b/fs/attr.c
@@ -29,13 +29,13 @@ int inode_change_ok(struct inode *inode, struct iattr *attr)
 
         /* Make sure a caller can chown. */
         if ((ia_valid & ATTR_UID) &&
-            (current->fsuid != inode->i_uid ||
+            (current_fsuid() != inode->i_uid ||
              attr->ia_uid != inode->i_uid) && !capable(CAP_CHOWN))
                 goto error;
 
         /* Make sure caller can chgrp. */
         if ((ia_valid & ATTR_GID) &&
-            (current->fsuid != inode->i_uid ||
+            (current_fsuid() != inode->i_uid ||
             (!in_group_p(attr->ia_gid) && attr->ia_gid != inode->i_gid)) &&
             !capable(CAP_CHOWN))
                 goto error;