Merge to Fedora Core 2 kernel-2.6.8-1.521

[linux-2.6.git] / mm / fremap.c

diff --git a/mm/fremap.c b/mm/fremap.c
index 0babe11..2f211f5 100644 (file)
--- a/mm/fremap.c
+++ b/mm/fremap.c
@@ -57,6 +57,8 @@ static inline void zap_pte(struct mm_struct *mm, struct vm_area_struct *vma,
 int install_page(struct mm_struct *mm, struct vm_area_struct *vma,
                unsigned long addr, struct page *page, pgprot_t prot)
 {
+       struct inode *inode;
+       pgoff_t size;
        int err = -ENOMEM;
        pte_t *pte;
        pgd_t *pgd;
@@ -77,6 +79,16 @@ int install_page(struct mm_struct *mm, struct vm_area_struct *vma,
        if (!pte)
                goto err_unlock;
 
+       /*
+        * This page may have been truncated. Tell the
+        * caller about it.
+        */
+       err = -EINVAL;
+       inode = vma->vm_file->f_mapping->host;
+       size = (i_size_read(inode) + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
+       if (!page->mapping || page->index >= size)
+               goto err_unlock;
+
        zap_pte(mm, vma, addr, pte);
 
        // mm->rss++;