Re: [PATCH 1/4] container_of: add container_of_const() that preserves const-ness of the pointer

From: Jason Gunthorpe
Date: Thu Dec 01 2022 - 19:48:56 EST


On Thu, Dec 01, 2022 at 08:30:54PM +0100, Greg Kroah-Hartman wrote:
> container_of does not preserve the const-ness of a pointer that is
> passed into it, which can cause C code that passes in a const pointer to
> get a pointer back that is not const and then scribble all over the data
> in it. To prevent this, container_of_const() will preserve the const
> status of the pointer passed into it using the newly available _Generic()
> method.
>
> Co-developed-by: Jason Gunthorpe <jgg@xxxxxxxx>
> Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
> Cc: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx>
> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>
> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> ---
> include/linux/container_of.h | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)

For the whole series

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Jason