diff options
Diffstat (limited to 'drivers/char/mem.c')
| -rw-r--r-- | drivers/char/mem.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/drivers/char/mem.c b/drivers/char/mem.c index 970e1242a282..6aefe5370e5b 100644 --- a/drivers/char/mem.c +++ b/drivers/char/mem.c @@ -343,6 +343,10 @@ 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; + /* Does it even fit in phys_addr_t? */ + if (offset >> PAGE_SHIFT != vma->vm_pgoff) + return -EINVAL; + /* It's illegal to wrap around the end of the physical address space. */ if (offset + (phys_addr_t)size - 1 < offset) return -EINVAL; |