RE: [PATCH 2/3] udmabuf: also check for F_SEAL_FUTURE_WRITE

[Kasireddy, Vivek]

> Subject: [PATCH 2/3] udmabuf: also check for F_SEAL_FUTURE_WRITE
> 
> When F_SEAL_FUTURE_WRITE was introduced, it was overlooked that
> udmabuf
> must reject memfds with this flag, just like ones with F_SEAL_WRITE.
> Fix it by adding F_SEAL_FUTURE_WRITE to SEALS_DENIED.
> 
> Fixes: ab3948f58ff8 ("mm/memfd: add an F_SEAL_FUTURE_WRITE seal to
> memfd")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Jann Horn <jannh@xxxxxxxxxx>
> ---
>  drivers/dma-buf/udmabuf.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c
> index
> 662b9a26e06668bf59ab36d07c0648c7b02ee5ae..8ce77f5837d71a73be677ca
> d014e05f29706057d 100644
> --- a/drivers/dma-buf/udmabuf.c
> +++ b/drivers/dma-buf/udmabuf.c
> @@ -297,7 +297,7 @@ static const struct dma_buf_ops udmabuf_ops = {
>  };
> 
>  #define SEALS_WANTED (F_SEAL_SHRINK)
> -#define SEALS_DENIED (F_SEAL_WRITE)
> +#define SEALS_DENIED (F_SEAL_WRITE|F_SEAL_FUTURE_WRITE)
Acked-by: Vivek Kasireddy <vivek.kasireddy@xxxxxxxxx>

> 
>  static int check_memfd_seals(struct file *memfd)
>  {
> 
> --
> 2.47.0.338.g60cca15819-goog