[PATCH] SELinux: Add security hook definition for getioprio and insert hooks
Add a new security hook definition for the sys_ioprio_get operation. At
present, the SELinux hook function implementation for this hook is
identical to the getscheduler implementation but a separate hook is
introduced to allow this check to be specialized in the future if
necessary.
This patch also creates a helper function get_task_ioprio which handles the
access check in addition to retrieving the ioprio value for the task.
Signed-off-by: David Quigley <dpquigl@tycho.nsa.gov>
Acked-by: Stephen Smalley <sds@tycho.nsa.gov>
Signed-off-by: James Morris <jmorris@namei.org>
Cc: Jens Axboe <axboe@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/fs/ioprio.c b/fs/ioprio.c
index 7fa76ed..93aa571 100644
--- a/fs/ioprio.c
+++ b/fs/ioprio.c
@@ -125,11 +125,24 @@
return ret;
}
+static int get_task_ioprio(struct task_struct *p)
+{
+ int ret;
+
+ ret = security_task_getioprio(p);
+ if (ret)
+ goto out;
+ ret = p->ioprio;
+out:
+ return ret;
+}
+
asmlinkage long sys_ioprio_get(int which, int who)
{
struct task_struct *g, *p;
struct user_struct *user;
int ret = -ESRCH;
+ int tmpio;
read_lock_irq(&tasklist_lock);
switch (which) {
@@ -139,16 +152,19 @@
else
p = find_task_by_pid(who);
if (p)
- ret = p->ioprio;
+ ret = get_task_ioprio(p);
break;
case IOPRIO_WHO_PGRP:
if (!who)
who = process_group(current);
do_each_task_pid(who, PIDTYPE_PGID, p) {
+ tmpio = get_task_ioprio(p);
+ if (tmpio < 0)
+ continue;
if (ret == -ESRCH)
- ret = p->ioprio;
+ ret = tmpio;
else
- ret = ioprio_best(ret, p->ioprio);
+ ret = ioprio_best(ret, tmpio);
} while_each_task_pid(who, PIDTYPE_PGID, p);
break;
case IOPRIO_WHO_USER:
@@ -163,10 +179,13 @@
do_each_thread(g, p) {
if (p->uid != user->uid)
continue;
+ tmpio = get_task_ioprio(p);
+ if (tmpio < 0)
+ continue;
if (ret == -ESRCH)
- ret = p->ioprio;
+ ret = tmpio;
else
- ret = ioprio_best(ret, p->ioprio);
+ ret = ioprio_best(ret, tmpio);
} while_each_thread(g, p);
if (who)
