diff options
Diffstat (limited to 'drivers/char/mem.c')
| -rw-r--r-- | drivers/char/mem.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 7e4a9d1296bb..6e0cbe092220 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -340,6 +340,11 @@ static const struct vm_operations_struct mmap_mem_ops = { static int mmap_mem(struct file *file, struct vm_area_struct *vma) { size_t size = vma->vm_end - vma->vm_start; + phys_addr_t offset = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT; + + /* It's illegal to wrap around the end of the physical address space. */ + if (offset + (phys_addr_t)size < offset) + return -EINVAL; if (!valid_mmap_phys_addr_range(vma->vm_pgoff, size)) return -EINVAL; |