gpu: host1x: Fix error handling

[karo-tx-linux.git] / drivers / char / mem.c

diff --git a/drivers/char/mem.c b/drivers/char/mem.c
index 7e4a9d1296bb7fb666f6b37ced2757a8585b7d75..6e0cbe09222059f0d8e8ccf821edfee5c575703e 100644 (file)
--- 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;