UPSTREAM: ANDROID: binder: re-order some conditions
authorDan Carpenter <dan.carpenter@oracle.com>
Thu, 29 Mar 2018 09:14:40 +0000 (12:14 +0300)
committerMartijn Coenen <maco@android.com>
Tue, 17 Jul 2018 09:14:21 +0000 (11:14 +0200)
It doesn't make any difference to runtime but I've switched these two
checks to make my static checker happy.

The problem is that "buffer->data_size" is user controlled and if it's
less than "sizeo(*hdr)" then that means "offset" can be more than
"buffer->data_size".  It's just cleaner to check it in the other order.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Martijn Coenen <maco@android.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
(cherry picked from commit 361f2ddbb0c9f9b4f336025a7bd0212cea4a34f0)

Change-Id: I098d525ba63d125caa9840e6e1d5004bf70edc3c

drivers/android/binder.c

index 5ddbe9c..754a320 100644 (file)
@@ -2214,8 +2214,8 @@ static size_t binder_validate_object(struct binder_buffer *buffer, u64 offset)
        struct binder_object_header *hdr;
        size_t object_size = 0;
 
-       if (offset > buffer->data_size - sizeof(*hdr) ||
-           buffer->data_size < sizeof(*hdr) ||
+       if (buffer->data_size < sizeof(*hdr) ||
+           offset > buffer->data_size - sizeof(*hdr) ||
            !IS_ALIGNED(offset, sizeof(u32)))
                return 0;