Re: [PATCH v8 5/7] mseal sysmap: uprobe mapping
From: Liam R. Howlett
Date: Mon Mar 03 2025 - 10:08:08 EST
* jeffxu@xxxxxxxxxxxx <jeffxu@xxxxxxxxxxxx> [250303 00:09]:
> From: Jeff Xu <jeffxu@xxxxxxxxxxxx>
>
> Provide support to mseal the uprobe mapping.
>
> Unlike other system mappings, the uprobe mapping is not
> established during program startup. However, its lifetime is the same
> as the process's lifetime. It could be sealed from creation.
>
> Test was done with perf tool, and observe the uprobe mapping is sealed.
>
> Signed-off-by: Jeff Xu <jeffxu@xxxxxxxxxxxx>
Reviewed-by: Liam R. Howlett <Liam.Howlett@xxxxxxxxxx>
> ---
> kernel/events/uprobes.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c
> index bf2a87a0a378..98632bc47216 100644
> --- a/kernel/events/uprobes.c
> +++ b/kernel/events/uprobes.c
> @@ -1683,7 +1683,8 @@ static int xol_add_vma(struct mm_struct *mm, struct xol_area *area)
> }
>
> vma = _install_special_mapping(mm, area->vaddr, PAGE_SIZE,
> - VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO,
> + VM_EXEC|VM_MAYEXEC|VM_DONTCOPY|VM_IO|
> + VM_SEALED_SYSMAP,
> &xol_mapping);
> if (IS_ERR(vma)) {
> ret = PTR_ERR(vma);
> --
> 2.48.1.711.g2feabab25a-goog
>