CRED: Wrap task credential accesses in the core kernel
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>
Cc: linux-audit@redhat.com
Cc: containers@lists.linux-foundation.org
Cc: linux-mm@kvack.org
Signed-off-by: James Morris <jmorris@namei.org>
diff --git a/kernel/sys.c b/kernel/sys.c
index 31deba8..ed5c29c 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -114,10 +114,10 @@
static int set_one_prio(struct task_struct *p, int niceval, int error)
{
+ uid_t euid = current_euid();
int no_nice;
- if (p->uid != current->euid &&
- p->euid != current->euid && !capable(CAP_SYS_NICE)) {
+ if (p->uid != euid && p->euid != euid && !capable(CAP_SYS_NICE)) {
error = -EPERM;
goto out;
}
@@ -176,16 +176,16 @@
case PRIO_USER:
user = current->user;
if (!who)
- who = current->uid;
+ who = current_uid();
else
- if ((who != current->uid) && !(user = find_user(who)))
+ if (who != current_uid() && !(user = find_user(who)))
goto out_unlock; /* No processes for this user */
do_each_thread(g, p)
if (p->uid == who)
error = set_one_prio(p, niceval, error);
while_each_thread(g, p);
- if (who != current->uid)
+ if (who != current_uid())
free_uid(user); /* For find_user() */
break;
}
@@ -238,9 +238,9 @@
case PRIO_USER:
user = current->user;
if (!who)
- who = current->uid;
+ who = current_uid();
else
- if ((who != current->uid) && !(user = find_user(who)))
+ if (who != current_uid() && !(user = find_user(who)))
goto out_unlock; /* No processes for this user */
do_each_thread(g, p)
@@ -250,7 +250,7 @@
retval = niceval;
}
while_each_thread(g, p);
- if (who != current->uid)
+ if (who != current_uid())
free_uid(user); /* for find_user() */
break;
}