1 files changed, 12 insertions, 14 deletions

diff --git a/kernel/compat.c b/kernel/compat.c
index f6c204f07ea6..5adab05a3172 100644
--- a/kernel/compat.c
+++ b/kernel/compat.c
@@ -25,6 +25,7 @@
 #include <linux/posix-timers.h>
 #include <linux/times.h>
 #include <linux/ptrace.h>
+#include <linux/gfp.h>
 
 #include <asm/uaccess.h>
 
@@ -494,29 +495,26 @@ asmlinkage long compat_sys_sched_getaffinity(compat_pid_t pid, unsigned int len,
 {
         int ret;
         cpumask_var_t mask;
-        unsigned long *k;
-        unsigned int min_length = cpumask_size();
-
-        if (nr_cpu_ids <= BITS_PER_COMPAT_LONG)
-                min_length = sizeof(compat_ulong_t);
 
-        if (len < min_length)
+        if ((len * BITS_PER_BYTE) < nr_cpu_ids)
+                return -EINVAL;
+        if (len & (sizeof(compat_ulong_t)-1))
                 return -EINVAL;
 
         if (!alloc_cpumask_var(&mask, GFP_KERNEL))
                 return -ENOMEM;
 
         ret = sched_getaffinity(pid, mask);
-        if (ret < 0)
-                goto out;
+        if (ret == 0) {
+                size_t retlen = min_t(size_t, len, cpumask_size());
 
-        k = cpumask_bits(mask);
-        ret = compat_put_bitmap(user_mask_ptr, k, min_length * 8);
-        if (ret == 0)
-                ret = min_length;
-
-out:
+                if (compat_put_bitmap(user_mask_ptr, cpumask_bits(mask), retlen * 8))
+                        ret = -EFAULT;
+                else
+                        ret = retlen;
+        }
         free_cpumask_var(mask);
+
         return ret;
 }