Re: [patch 03/18] entry: Provide [syscall_]enter_from_user_mode_randomize_stack()

Philippe Mathieu-Daudé <[email protected]> Thu, 9 Jul 2026 13:15:11 +0200
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Message-ID <[email protected]> 
On 7/7/26 21:06, Thomas Gleixner wrote:
> Randomizing the syscall stack can only happen after state is established
> via enter_from_user_mode() or syscall_enter_from_user_mode(). The earlier
> it happens the better.
> 
> Provide two new macros to consolidate that:
> 
>    - enter_from_user_mode_randomize_stack()
> 	enter_from_user_mode();
> 	add_random_kstack_offset_irqsoff();
> 
>    - syscall_enter_from_user_mode_randomize_stack()
> 	enter_from_user_mode_randomize_stack();
> 	syscall_enter_from_user_mode_work();
>      
> to reduce boiler plate code.
> 
> Those are macros and not inline functions as the latter would limit the
> stack randomization scope to the inline function itself.
> 
> Signed-off-by: Thomas Gleixner <[email protected]>
> ---
>   include/linux/entry-common.h |   56 +++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 56 insertions(+)

Reviewed-by: Philippe Mathieu-Daudé <[email protected]>