From 74801e50d5b89329e6c02b8bd924a41234f76316 Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Tue, 16 Jan 2018 15:51:50 -0800 Subject: [PATCH] nfp: bpf: reject program on instructions unknown to the JIT compiler If an eBPF instruction is unknown to the driver JIT compiler, we can reject the program at verification time. Signed-off-by: Quentin Monnet Reviewed-by: Jakub Kicinski Reviewed-by: Jiong Wang Signed-off-by: Daniel Borkmann --- drivers/net/ethernet/netronome/nfp/bpf/jit.c | 5 +++++ drivers/net/ethernet/netronome/nfp/bpf/main.h | 1 + drivers/net/ethernet/netronome/nfp/bpf/verifier.c | 6 ++++++ 3 files changed, 12 insertions(+) diff --git a/drivers/net/ethernet/netronome/nfp/bpf/jit.c b/drivers/net/ethernet/netronome/nfp/bpf/jit.c index cdc949f..56451ed 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/jit.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/jit.c @@ -2907,6 +2907,11 @@ void nfp_bpf_jit_prepare(struct nfp_prog *nfp_prog, unsigned int cnt) } } +bool nfp_bpf_supported_opcode(u8 code) +{ + return !!instr_cb[code]; +} + void *nfp_bpf_relo_for_vnic(struct nfp_prog *nfp_prog, struct nfp_bpf_vnic *bv) { unsigned int i; diff --git a/drivers/net/ethernet/netronome/nfp/bpf/main.h b/drivers/net/ethernet/netronome/nfp/bpf/main.h index b80e75a..c476bca 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/main.h +++ b/drivers/net/ethernet/netronome/nfp/bpf/main.h @@ -324,6 +324,7 @@ struct nfp_bpf_vnic { void nfp_bpf_jit_prepare(struct nfp_prog *nfp_prog, unsigned int cnt); int nfp_bpf_jit(struct nfp_prog *prog); +bool nfp_bpf_supported_opcode(u8 code); extern const struct bpf_prog_offload_ops nfp_bpf_analyzer_ops; diff --git a/drivers/net/ethernet/netronome/nfp/bpf/verifier.c b/drivers/net/ethernet/netronome/nfp/bpf/verifier.c index 81dab46..479f602 100644 --- a/drivers/net/ethernet/netronome/nfp/bpf/verifier.c +++ b/drivers/net/ethernet/netronome/nfp/bpf/verifier.c @@ -290,6 +290,12 @@ nfp_verify_insn(struct bpf_verifier_env *env, int insn_idx, int prev_insn_idx) meta = nfp_bpf_goto_meta(nfp_prog, meta, insn_idx, env->prog->len); nfp_prog->verifier_meta = meta; + if (!nfp_bpf_supported_opcode(meta->insn.code)) { + pr_vlog(env, "instruction %#02x not supported\n", + meta->insn.code); + return -EINVAL; + } + if (meta->insn.src_reg >= MAX_BPF_REG || meta->insn.dst_reg >= MAX_BPF_REG) { pr_vlog(env, "program uses extended registers - jit hardening?\n"); -- 2.7.4