From dc881f294eb957bded69b5e7f2f72831e2d00ac4 Mon Sep 17 00:00:00 2001 From: Ian Abbott Date: Tue, 18 Sep 2012 19:46:57 +0100 Subject: [PATCH] staging: comedi: fix sparse warning in do_devconfig_ioctl() For the COMEDI_DEVCONFIG ioctl, the user application may embed a pointer to firmware data within a designated element (or two elements for 64-bit pointers) of the `options[]` array in the `struct comedi_devconfig`. `do_devconfig_ioctl()` calls `comedi_aux_data()` to extract the pointer value. It needs to be treated as a `__user` pointer so the firmware data can be copied into kernel memory, so cast the result of `comedi_aux_data()` to avoid a "sparse" warning. This is not ideal but `comedi_aux_data()` is called elsewhere in a wholly kernel memory context so we can't just change its return type to include the `__user` tag. Signed-off-by: Ian Abbott Signed-off-by: Greg Kroah-Hartman --- drivers/staging/comedi/comedi_fops.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/staging/comedi/comedi_fops.c b/drivers/staging/comedi/comedi_fops.c index 626fa72..9b9d4e8 100644 --- a/drivers/staging/comedi/comedi_fops.c +++ b/drivers/staging/comedi/comedi_fops.c @@ -370,7 +370,8 @@ static int do_devconfig_ioctl(struct comedi_device *dev, return -ENOMEM; if (copy_from_user(aux_data, - comedi_aux_data(it.options, 0), aux_len)) { + (unsigned char __user * + )comedi_aux_data(it.options, 0), aux_len)) { vfree(aux_data); return -EFAULT; } -- 2.7.4