Re: [Qemu-devel] [PATCH v3] seccomp: add cacheflush to whitelist

[Andrew Jones]

On Mon, Nov 02, 2015 at 11:53:26PM +0100, Andrew Jones wrote:
> cacheflush is an arm-specific syscall that qemu built for arm
> uses. Add it to the whitelist, but only if we're linking with
> a recent enough libseccomp.
> 
> Signed-off-by: Andrew Jones <address@hidden>
> ---
> v3: deal with major and minor version number bumps
> v2: only add cacheflush if libseccomp supports it
> 
>  qemu-seccomp.c | 13 ++++++++++++-
>  1 file changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/qemu-seccomp.c b/qemu-seccomp.c
> index 80d034a8d5190..c831fe83ad500 100644
> --- a/qemu-seccomp.c
> +++ b/qemu-seccomp.c
> @@ -16,6 +16,14 @@
>  #include <seccomp.h>
>  #include "sysemu/seccomp.h"
>  
> +#if SCMP_VER_MAJOR >= 3
> +  #define HAVE_CACHEFLUSH
> +#elif SCMP_VER_MAJOR == 2 && SCMP_VER_MINOR >= 3
> +  #define HAVE_CACHEFLUSH
> +#elif SCMP_VER_MAJOR == 2 && SCMP_VER_MINOR == 2 && SCMP_VER_MICRO >= 3
> +  #define HAVE_CACHEFLUSH
> +#endif
> +
>  struct QemuSeccompSyscall {
>      int32_t num;
>      uint8_t priority;
> @@ -238,7 +246,10 @@ static const struct QemuSeccompSyscall 
> seccomp_whitelist[] = {
>      { SCMP_SYS(inotify_init1), 240 },
>      { SCMP_SYS(inotify_add_watch), 240 },
>      { SCMP_SYS(mbind), 240 },
> -    { SCMP_SYS(memfd_create), 240 }
> +    { SCMP_SYS(memfd_create), 240 },
> +#ifdef HAVE_CACHEFLUSH
> +    { SCMP_SYS(cacheflush), 240 },
> +#endif
>  };
>  
>  int seccomp_start(void)
> -- 
> 1.8.3.1
>

Eduardo, ping?

drew