ovl: use O_LARGEFILE in ovl_copy_up()

Orabug: 26619890

Open the lower file with O_LARGEFILE in ovl_copy_up().

Pass O_LARGEFILE unconditionally in ovl_copy_up_data() as it's purely for
catching 32-bit userspace dealing with a file large enough that it'll be
mishandled if the application isn't aware that there might be an integer
overflow.  Inside the kernel, there shouldn't be any problems.

Reported-by: Ulrich Obergfell <uobergfe@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: <stable@vger.kernel.org> # v3.18+
(cherry picked from commit 0480334fa60488d12ae101a02d7d9e1a3d03d7dd)
Signed-off-by: Somasundaram Krishnasamy <somasundaram.krishnasamy@oracle.com>
Reviewed-by: Kirtikar Kashyap <kirtikar.kashyap@oracle.com>
Reviewed-by:  Ethan Zhao <ethan.zhao@oracle.com>

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index 860cdae0c6e7157a5cd335f92dbe300b55fb5b9e..779be609abce4ca849bab8c95c01f897b384c37d 100644 (file)
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -92,11 +92,11 @@ static int ovl_copy_up_data(struct path *old, struct path *new, loff_t len)
        if (len == 0)
                return 0;
 
-       old_file = ovl_path_open(old, O_RDONLY);
+       old_file = ovl_path_open(old, O_LARGEFILE | O_RDONLY);
        if (IS_ERR(old_file))
                return PTR_ERR(old_file);
 
-       new_file = ovl_path_open(new, O_WRONLY);
+       new_file = ovl_path_open(new, O_LARGEFILE | O_WRONLY);
        if (IS_ERR(new_file)) {
                error = PTR_ERR(new_file);
                goto out_fput;