x86: Do not free zero sized per cpu areas

[safe/jmp/linux-2.6] / kernel / sched.c

diff --git a/kernel/sched.c b/kernel/sched.c
index 9ab3cd7..49d2fa7 100644 (file)
--- a/kernel/sched.c
+++ b/kernel/sched.c
@@ -2650,7 +2650,7 @@ void wake_up_new_task(struct task_struct *p, unsigned long clone_flags)
 {
        unsigned long flags;
        struct rq *rq;
-       int cpu = get_cpu();
+       int cpu __maybe_unused = get_cpu();
 
 #ifdef CONFIG_SMP
        /*
@@ -4902,7 +4902,9 @@ SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len,
        int ret;
        cpumask_var_t mask;
 
-       if (len < cpumask_size())
+       if (len < nr_cpu_ids)
+               return -EINVAL;
+       if (len & (sizeof(unsigned long)-1))
                return -EINVAL;
 
        if (!alloc_cpumask_var(&mask, GFP_KERNEL))
@@ -4910,10 +4912,12 @@ SYSCALL_DEFINE3(sched_getaffinity, pid_t, pid, unsigned int, len,
 
        ret = sched_getaffinity(pid, mask);
        if (ret == 0) {
-               if (copy_to_user(user_mask_ptr, mask, cpumask_size()))
+               size_t retlen = min_t(size_t, len, cpumask_size());
+
+               if (copy_to_user(user_mask_ptr, mask, retlen))
                        ret = -EFAULT;
                else
-                       ret = cpumask_size();
+                       ret = retlen;
        }
        free_cpumask_var(mask);