1 files changed, 23 insertions, 3 deletions

diff --git a/mm/madvise.c b/mm/madvise.c
index b9ce574827c8..76eb4193acdd 100644
--- a/mm/madvise.c
+++ b/mm/madvise.c
@@ -123,8 +123,7 @@ static long madvise_willneed(struct vm_area_struct * vma,
                 end = vma->vm_end;
         end = ((end - vma->vm_start) >> PAGE_SHIFT) + vma->vm_pgoff;
 
-        force_page_cache_readahead(file->f_mapping,
-                        file, start, max_sane_readahead(end - start));
+        force_page_cache_readahead(file->f_mapping, file, start, end - start);
         return 0;
 }
 
@@ -239,12 +238,30 @@ madvise_vma(struct vm_area_struct *vma, struct vm_area_struct **prev,
                 break;
 
         default:
-                error = -EINVAL;
+                BUG();
                 break;
         }
         return error;
 }
 
+static int
+madvise_behavior_valid(int behavior)
+{
+        switch (behavior) {
+        case MADV_DOFORK:
+        case MADV_DONTFORK:
+        case MADV_NORMAL:
+        case MADV_SEQUENTIAL:
+        case MADV_RANDOM:
+        case MADV_REMOVE:
+        case MADV_WILLNEED:
+        case MADV_DONTNEED:
+                return 1;
+
+        default:
+                return 0;
+        }
+}
 /*
  * The madvise(2) system call.
  *
@@ -290,6 +307,9 @@ SYSCALL_DEFINE3(madvise, unsigned long, start, size_t, len_in, int, behavior)
         int write;
         size_t len;
 
+        if (!madvise_behavior_valid(behavior))
+                return error;
+
         write = madvise_need_mmap_write(behavior);
         if (write)
                 down_write(&current->mm->mmap_sem);