Re: [PATCH v7 1/7] mseal, system mappings: kernel config and header change

From: Liam R. Howlett
Date: Tue Feb 25 2025 - 10:25:17 EST


* jeffxu@xxxxxxxxxxxx <jeffxu@xxxxxxxxxxxx> [250224 17:52]:
> From: Jeff Xu <jeffxu@xxxxxxxxxxxx>
>
> Provide infrastructure to mseal system mappings. Establish
> two kernel configs (CONFIG_MSEAL_SYSTEM_MAPPINGS,
> ARCH_HAS_MSEAL_SYSTEM_MAPPINGS) and VM_SEALED_SYSMAP
> macro for future patches.
>
> Signed-off-by: Jeff Xu <jeffxu@xxxxxxxxxxxx>
> ---
> include/linux/mm.h | 10 ++++++++++
> init/Kconfig | 18 ++++++++++++++++++
> security/Kconfig | 18 ++++++++++++++++++
> 3 files changed, 46 insertions(+)
>
> diff --git a/include/linux/mm.h b/include/linux/mm.h
> index 7b1068ddcbb7..8b800941678d 100644
> --- a/include/linux/mm.h
> +++ b/include/linux/mm.h
> @@ -4155,4 +4155,14 @@ int arch_get_shadow_stack_status(struct task_struct *t, unsigned long __user *st
> int arch_set_shadow_stack_status(struct task_struct *t, unsigned long status);
> int arch_lock_shadow_stack_status(struct task_struct *t, unsigned long status);
>
> +
> +/*
> + * mseal of userspace process's system mappings.
> + */
> +#ifdef CONFIG_MSEAL_SYSTEM_MAPPINGS
> +#define VM_SEALED_SYSMAP VM_SEALED
> +#else
> +#define VM_SEALED_SYSMAP VM_NONE
> +#endif
> +
> #endif /* _LINUX_MM_H */
> diff --git a/init/Kconfig b/init/Kconfig
> index d0d021b3fa3b..07435e33f965 100644
> --- a/init/Kconfig
> +++ b/init/Kconfig
> @@ -1882,6 +1882,24 @@ config ARCH_HAS_MEMBARRIER_CALLBACKS
> config ARCH_HAS_MEMBARRIER_SYNC_CORE
> bool
>
> +config ARCH_HAS_MSEAL_SYSTEM_MAPPINGS

I think we said ARCH_SUPPORTS_ for software features in v5 of the series
[1]. Can we also make this change please?

...

Thanks,
Liam

[1]. https://lore.kernel.org/all/202502131142.F5EE115C3A@keescook/