This patchset introduces a new operation and a new flag
to split the SECCOMP_SET_MODE_FILTER process into two steps:
load filter and attach filter. Thus we can reuse the filter.
The new SECCOMP_LOAD_FILTER loads the filter and returns a fd
which can be pinned to bpffs. This extends the lifetime of the
filter and thus can be reused by different processes.
With this new operation, we can eliminate a hot path of JITing
BPF program (the filter) where we apply the same seccomp filter
to thousands of micro VMs on a bare metal instance.
The new flag SECCOMP_FILTER_FLAG_BPF_PROG_FD is used to attach
a filter which is loaded via SECCOMP_LOAD_FILTER and represented
by a seccomp bpf prog fd. The fd is either returned from
SECCOMP_LOAD_FILTER or obtained from bpffs using bpf syscall.
Change logs:
v1 -> v2:
- Add a flag to attach filter from fd
- Update selftests
RFC -> v1:
- Addressed comments from Kees
- Reuse filter copy/create code (patch 1)
- Add a selftest (patch 4)
Hengqi Chen (5):
seccomp: Refactor filter copy/create for reuse
seccomp, bpf: Introduce SECCOMP_LOAD_FILTER operation
seccomp: Introduce new flag SECCOMP_FILTER_FLAG_BPF_PROG_FD
selftests/seccomp: Test seccomp filter load and attach
selftests/bpf: Skip BPF_PROG_TYPE_SECCOMP-related tests
include/linux/seccomp.h | 3 +-
include/uapi/linux/bpf.h | 1 +
include/uapi/linux/seccomp.h | 3 +
kernel/seccomp.c | 170 +++++++++++++++---
tools/include/uapi/linux/bpf.h | 1 +
.../selftests/bpf/prog_tests/libbpf_probes.c | 3 +-
.../selftests/bpf/prog_tests/libbpf_str.c | 3 +
tools/testing/selftests/seccomp/seccomp_bpf.c | 44 +++++
8 files changed, 197 insertions(+), 31 deletions(-)
--
2.34.1
