1 files changed, 5 insertions, 7 deletions

diff --git a/kernel/sys.c b/kernel/sys.c
index 20ccfb5da6af..9814e43fb23b 100644
--- a/kernel/sys.c
+++ b/kernel/sys.c
@@ -162,6 +162,7 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
         if (niceval > 19)
                 niceval = 19;
 
+        rcu_read_lock();
         read_lock(&tasklist_lock);
         switch (which) {
                 case PRIO_PROCESS:
@@ -199,6 +200,7 @@ SYSCALL_DEFINE3(setpriority, int, which, int, who, int, niceval)
         }
 out_unlock:
         read_unlock(&tasklist_lock);
+        rcu_read_unlock();
 out:
         return error;
 }
@@ -220,6 +222,7 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
         if (which > PRIO_USER || which < PRIO_PROCESS)
                 return -EINVAL;
 
+        rcu_read_lock();
         read_lock(&tasklist_lock);
         switch (which) {
                 case PRIO_PROCESS:
@@ -265,6 +268,7 @@ SYSCALL_DEFINE2(getpriority, int, which, int, who)
         }
 out_unlock:
         read_unlock(&tasklist_lock);
+        rcu_read_unlock();
 
         return retval;
 }
@@ -567,13 +571,7 @@ static int set_user(struct cred *new)
         if (!new_user)
                 return -EAGAIN;
 
-        if (!task_can_switch_user(new_user, current)) {
-                free_uid(new_user);
-                return -EINVAL;
-        }
-
-        if (atomic_read(&new_user->processes) >=
-                                current->signal->rlim[RLIMIT_NPROC].rlim_cur &&
+        if (atomic_read(&new_user->processes) >= rlimit(RLIMIT_NPROC) &&
                         new_user != INIT_USER) {
                 free_uid(new_user);
                 return -EAGAIN;