hugepage: fix broken check for offset alignment in hugepage mappings

[safe/jmp/linux-2.6] / fs / hugetlbfs / inode.c

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index c848a19..950c2fb 100644 (file)
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -82,14 +82,19 @@ static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
        int ret;
 
        /*
-        * vma alignment has already been checked by prepare_hugepage_range.
-        * If you add any error returns here, do so after setting VM_HUGETLB,
-        * so is_vm_hugetlb_page tests below unmap_region go the right way
-        * when do_mmap_pgoff unwinds (may be important on powerpc and ia64).
+        * vma address alignment (but not the pgoff alignment) has
+        * already been checked by prepare_hugepage_range.  If you add
+        * any error returns here, do so after setting VM_HUGETLB, so
+        * is_vm_hugetlb_page tests below unmap_region go the right
+        * way when do_mmap_pgoff unwinds (may be important on powerpc
+        * and ia64).
         */
        vma->vm_flags |= VM_HUGETLB | VM_RESERVED;
        vma->vm_ops = &hugetlb_vm_ops;
 
+       if (vma->vm_pgoff & ~(HPAGE_MASK >> PAGE_SHIFT))
+               return -EINVAL;
+
        vma_len = (loff_t)(vma->vm_end - vma->vm_start);
 
        mutex_lock(&inode->i_mutex);
@@ -132,7 +137,7 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
                return -ENOMEM;
 
        if (flags & MAP_FIXED) {
-               if (prepare_hugepage_range(addr, len, pgoff))
+               if (prepare_hugepage_range(addr, len))
                        return -EINVAL;
                return addr;
        }