Re: [PATCH 1/2] memfd: export memfd_{add,get}_seals()

Mike Rapoport
2026-01-25T11:52:13Z

On Fri, Jan 23, 2026 at 10:58:50AM +0100, Pratyush Yadav wrote:
> From: "Pratyush Yadav (Google)" <pratyush@kernel.org>
>
> Support for preserving file seals will be added to memfd preservation
> using the Live Update Orchestrator (LUO). Export
> memfd_{add,get}_seals)() so memfd_luo can use them to manipulate the
> seals.
>
> Signed-off-by: Pratyush Yadav (Google) <pratyush@kernel.org>

Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>

> ---
> include/linux/memfd.h | 12 ++++++++++++
> mm/memfd.c | 4 ++--
> 2 files changed, 14 insertions(+), 2 deletions(-)
>
> diff --git a/include/linux/memfd.h b/include/linux/memfd.h
> index c328a7b356d0..b4fda09dab9f 100644
> --- a/include/linux/memfd.h
> +++ b/include/linux/memfd.h
> @@ -18,6 +18,8 @@ struct folio *memfd_alloc_folio(struct file *memfd, pgoff_t idx);
> */
> int memfd_check_seals_mmap(struct file *file, vm_flags_t *vm_flags_ptr);
> struct file *memfd_alloc_file(const char *name, unsigned int flags);
> +int memfd_get_seals(struct file *file);
> +int memfd_add_seals(struct file *file, unsigned int seals);
> #else
> static inline long memfd_fcntl(struct file *f, unsigned int c, unsigned int a)
> {
> @@ -37,6 +39,16 @@ static inline struct file *memfd_alloc_file(const char *name, unsigned int flags
> {
> return ERR_PTR(-EINVAL);
> }
> +
> +static inline int memfd_get_seals(struct file *file)
> +{
> + return -EINVAL;
> +}
> +
> +static inline int memfd_add_seals(struct file *file, unsigned int seals)
> +{
> + return -EINVAL;
> +}
> #endif
>
> #endif /* __LINUX_MEMFD_H */
> diff --git a/mm/memfd.c b/mm/memfd.c
> index f032c6052926..46c5508beea4 100644
> --- a/mm/memfd.c
> +++ b/mm/memfd.c
> @@ -228,7 +228,7 @@ static unsigned int *memfd_file_seals_ptr(struct file *file)
> F_SEAL_WRITE | \
> F_SEAL_FUTURE_WRITE)
>
> -static int memfd_add_seals(struct file *file, unsigned int seals)
> +int memfd_add_seals(struct file *file, unsigned int seals)
> {
> struct inode *inode = file_inode(file);
> unsigned int *file_seals;
> @@ -310,7 +310,7 @@ static int memfd_add_seals(struct file *file, unsigned int seals)
> return error;
> }
>
> -static int memfd_get_seals(struct file *file)
> +int memfd_get_seals(struct file *file)
> {
> unsigned int *seals = memfd_file_seals_ptr(file);
>
> --
> 2.52.0.457.g6b5491de43-goog
>

--
Sincerely yours,
Mike.