Messages in this thread | | | From | Geert Uytterhoeven <> | Date | Tue, 27 Oct 2020 10:52:39 +0100 | Subject | Re: [PATCH v2 seccomp 1/6] seccomp: Move config option SECCOMP to arch/Kconfig |
| |
Hi Yifei,
On Thu, Sep 24, 2020 at 2:48 PM YiFei Zhu <zhuyifei1999@gmail.com> wrote: > From: YiFei Zhu <yifeifz2@illinois.edu> > > In order to make adding configurable features into seccomp > easier, it's better to have the options at one single location, > considering easpecially that the bulk of seccomp code is > arch-independent. An quick look also show that many SECCOMP > descriptions are outdated; they talk about /proc rather than > prctl. > > As a result of moving the config option and keeping it default > on, architectures arm, arm64, csky, riscv, sh, and xtensa > did not have SECCOMP on by default prior to this and SECCOMP will > be default in this change. > > Architectures microblaze, mips, powerpc, s390, sh, and sparc > have an outdated depend on PROC_FS and this dependency is removed > in this change. > > Suggested-by: Jann Horn <jannh@google.com> > Link: https://lore.kernel.org/lkml/CAG48ez1YWz9cnp08UZgeieYRhHdqh-ch7aNwc4JRBnGyrmgfMg@mail.gmail.com/ > Signed-off-by: YiFei Zhu <yifeifz2@illinois.edu>
Thanks for your patch. which is now commit 282a181b1a0d66de ("seccomp: Move config option SECCOMP to arch/Kconfig") in v5.10-rc1.
> --- a/arch/Kconfig > +++ b/arch/Kconfig > @@ -458,6 +462,23 @@ config HAVE_ARCH_SECCOMP_FILTER > results in the system call being skipped immediately. > - seccomp syscall wired up > > +config SECCOMP > + def_bool y > + depends on HAVE_ARCH_SECCOMP > + prompt "Enable seccomp to safely compute untrusted bytecode" > + help > + This kernel feature is useful for number crunching applications > + that may need to compute untrusted bytecode during their > + execution. By using pipes or other transports made available to > + the process as file descriptors supporting the read/write > + syscalls, it's possible to isolate those applications in > + their own address space using seccomp. Once seccomp is > + enabled via prctl(PR_SET_SECCOMP), it cannot be disabled > + and the task is only allowed to execute a few safe syscalls > + defined by each seccomp mode. > + > + If unsure, say Y. Only embedded should say N here. > +
Please tell me why SECCOMP is special, and deserves to default to be enabled. Is it really that critical, given only 13.5 (half of sparc ;-) out of 24 architectures implement support for it?
Thanks!
Gr{oetje,eeting}s,
Geert
-- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org
In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds
| |