From: Jeff Xu <jeffxu@chromium.org>

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@chromium.org>
---
 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

On Mon, Mar 03, 2025 at 05:09:19AM +0000, jeffxu@chromium.org wrote:
> From: Jeff Xu <jeffxu@chromium.org>
> 
> 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@chromium.org>

Reviewed-by: Kees Cook <kees@kernel.org>

-- 
Kees Cook

* jeffxu@chromium.org <jeffxu@chromium.org> [250303 00:09]:
> From: Jeff Xu <jeffxu@chromium.org>
> 
> 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@chromium.org>

Reviewed-by: Liam R. Howlett <Liam.Howlett@oracle.com>

> ---
>  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
>

On Mon, Mar 03, 2025 at 05:09:19AM +0000, jeffxu@chromium.org wrote:
> From: Jeff Xu <jeffxu@chromium.org>
>
> 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@chromium.org>

LGTM so:

Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>

> ---
>  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
>

On 03/03, jeffxu@chromium.org wrote:
>
> @@ -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);

Reviewed-by: Oleg Nesterov <oleg@redhat.com>