[PATCH] cxl/mem: return -EFAULT if copy_to_user() fails

[Dan Carpenter]

The copy_to_user() function returns the number of bytes remaining to be
copied, but we want to return -EFAULT if the copy doesn't complete.

Fixes: b754ffbbc0ee ("cxl/mem: Add basic IOCTL interface")
Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
---
 drivers/cxl/mem.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c
index 8331a2fc7667..d73ab363ad71 100644
--- a/drivers/cxl/mem.c
+++ b/drivers/cxl/mem.c
@@ -745,7 +745,10 @@ static int cxl_send_cmd(struct cxl_memdev *cxlmd,
        if (rc)
                return rc;
 
-       return copy_to_user(s, &send, sizeof(send));
+       if (copy_to_user(s, &send, sizeof(send)))
+               return -EFAULT;
+
+       return 0;
 }
 
 static long __cxl_memdev_ioctl(struct cxl_memdev *cxlmd, unsigned int cmd,
-- 
2.30.0