Merge git://git.kernel.org/pub/scm/linux/kernel/git/steve/gfs2-2.6-nmw

[pandora-kernel.git] / mm / fremap.c

diff --git a/mm/fremap.c b/mm/fremap.c
index 46f5dac..ec520c7 100644 (file)
--- a/mm/fremap.c
+++ b/mm/fremap.c
@@ -125,7 +125,6 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
 {
        struct mm_struct *mm = current->mm;
        struct address_space *mapping;
-       unsigned long end = start + size;
        struct vm_area_struct *vma;
        int err = -EINVAL;
        int has_write_lock = 0;
@@ -142,6 +141,10 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
        if (start + size <= start)
                return err;
 
+       /* Does pgoff wrap? */
+       if (pgoff + (size >> PAGE_SHIFT) < pgoff)
+               return err;
+
        /* Can we represent this offset inside this architecture's pte's? */
 #if PTE_FILE_MAX_BITS < BITS_PER_LONG
        if (pgoff + (size >> PAGE_SHIFT) >= (1UL << PTE_FILE_MAX_BITS))
@@ -168,7 +171,7 @@ SYSCALL_DEFINE5(remap_file_pages, unsigned long, start, unsigned long, size,
        if (!(vma->vm_flags & VM_CAN_NONLINEAR))
                goto out;
 
-       if (end <= start || start < vma->vm_start || end > vma->vm_end)
+       if (start < vma->vm_start || start + size > vma->vm_end)
                goto out;
 
        /* Must set VM_NONLINEAR before any pages are populated. */