pagevec_reinit(pvec);
}
+/*
+ * Mask used when checking the page offset value passed in via system
+ * calls. This value will be converted to a loff_t which is signed.
+ * Therefore, we want to check the upper PAGE_SHIFT + 1 bits of the
+ * value. The extra bit (- 1 in the shift value) is to take the sign
+ * bit into account.
+ */
+#define PGOFF_LOFFT_MAX \
+ (((1UL << (PAGE_SHIFT + 1)) - 1) << (BITS_PER_LONG - (PAGE_SHIFT + 1)))
+
static int hugetlbfs_file_mmap(struct file *file, struct vm_area_struct *vma)
{
struct inode *inode = file->f_path.dentry->d_inode;
vma->vm_flags |= VM_HUGETLB | VM_RESERVED;
vma->vm_ops = &hugetlb_vm_ops;
+ /*
+ * page based offset in vm_pgoff could be sufficiently large to
+ * overflow a (l)off_t when converted to byte offset.
+ */
+ if (vma->vm_pgoff & PGOFF_LOFFT_MAX)
+ return -EINVAL;
+
+ /* must be huge page aligned */
if (vma->vm_pgoff & (~huge_page_mask(h) >> PAGE_SHIFT))
return -EINVAL;
vma_len = (loff_t)(vma->vm_end - vma->vm_start);
+ len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
+ /* check for overflow */
+ if (len < vma_len)
+ return -EINVAL;
mutex_lock(&inode->i_mutex);
file_accessed(file);
ret = -ENOMEM;
- len = vma_len + ((loff_t)vma->vm_pgoff << PAGE_SHIFT);
-
if (hugetlb_reserve_pages(inode,
vma->vm_pgoff >> huge_page_order(h),
len >> huge_page_shift(h), vma,
ret = 0;
hugetlb_prefault_arch_hook(vma->vm_mm);
if (vma->vm_flags & VM_WRITE && inode->i_size < len)
- inode->i_size = len;
+ i_size_write(inode, len);
out:
mutex_unlock(&inode->i_mutex);