diff options
| author | Andy Lutomirski <luto@amacapital.net> | 2014-07-21 18:49:17 -0700 |
|---|---|---|
| committer | Kees Cook <keescook@chromium.org> | 2014-09-03 14:58:17 -0700 |
| commit | ff27f38e0ef978aee4c9f7e3a4f3403aae832de2 (patch) | |
| tree | 34fa7b7f8c1b74a29eed8f59de8d00c396433e14 | |
| parent | d39bd00deabe57420f2a3669eb71b0e0c4997184 (diff) | |
seccomp: Document two-phase seccomp and arch-provided seccomp_data
The description of how archs should implement seccomp filters was
still strictly correct, but it failed to describe the newly
available optimizations.
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Kees Cook <keescook@chromium.org>
| -rw-r--r-- | arch/Kconfig | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/arch/Kconfig b/arch/Kconfig index 0eae9df35b8..05d7a8a458d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -323,6 +323,17 @@ config HAVE_ARCH_SECCOMP_FILTER results in the system call being skipped immediately. - seccomp syscall wired up + For best performance, an arch should use seccomp_phase1 and + seccomp_phase2 directly. It should call seccomp_phase1 for all + syscalls if TIF_SECCOMP is set, but seccomp_phase1 does not + need to be called from a ptrace-safe context. It must then + call seccomp_phase2 if seccomp_phase1 returns anything other + than SECCOMP_PHASE1_OK or SECCOMP_PHASE1_SKIP. + + As an additional optimization, an arch may provide seccomp_data + directly to seccomp_phase1; this avoids multiple calls + to the syscall_xyz helpers for every syscall. + config SECCOMP_FILTER def_bool y depends on HAVE_ARCH_SECCOMP_FILTER && SECCOMP && NET |