From 9383191da4e40360a5d880fbe6bb03911c61621b Mon Sep 17 00:00:00 2001 From: Daniel Borkmann Date: Thu, 16 Feb 2017 22:24:49 +0100 Subject: [PATCH] bpf: remove stubs for cBPF from arch code Remove the dummy bpf_jit_compile() stubs for eBPF JITs and make that a single __weak function in the core that can be overridden similarly to the eBPF one. Also remove stale pr_err() mentions of bpf_jit_compile. Signed-off-by: Daniel Borkmann Acked-by: Alexei Starovoitov Signed-off-by: David S. Miller --- arch/arm64/net/bpf_jit_comp.c | 5 ----- arch/powerpc/net/bpf_jit_comp64.c | 2 -- arch/s390/net/bpf_jit_comp.c | 8 -------- arch/x86/net/bpf_jit_comp.c | 8 ++------ include/linux/filter.h | 6 +----- kernel/bpf/core.c | 12 +++++++++++- 6 files changed, 14 insertions(+), 27 deletions(-) diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index b2fc97a2c56c..c444408d5a8c 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -813,11 +813,6 @@ static inline void bpf_flush_icache(void *start, void *end) flush_icache_range((unsigned long)start, (unsigned long)end); } -void bpf_jit_compile(struct bpf_prog *prog) -{ - /* Nothing to do here. We support Internal BPF. */ -} - struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) { struct bpf_prog *tmp, *orig_prog = prog; diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index 73a5cf18fd84..f9ebd02260da 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -961,8 +961,6 @@ common_load: return 0; } -void bpf_jit_compile(struct bpf_prog *fp) { } - struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *fp) { u32 proglen; diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c index 167b31b186c1..6454efd22e63 100644 --- a/arch/s390/net/bpf_jit_comp.c +++ b/arch/s390/net/bpf_jit_comp.c @@ -1262,14 +1262,6 @@ static int bpf_jit_prog(struct bpf_jit *jit, struct bpf_prog *fp) return 0; } -/* - * Classic BPF function stub. BPF programs will be converted into - * eBPF and then bpf_int_jit_compile() will be called. - */ -void bpf_jit_compile(struct bpf_prog *fp) -{ -} - /* * Compile eBPF program "fp" */ diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c index bb660e53cbd6..26123d0ae13a 100644 --- a/arch/x86/net/bpf_jit_comp.c +++ b/arch/x86/net/bpf_jit_comp.c @@ -1067,13 +1067,13 @@ common_load: ilen = prog - temp; if (ilen > BPF_MAX_INSN_SIZE) { - pr_err("bpf_jit_compile fatal insn size error\n"); + pr_err("bpf_jit: fatal insn size error\n"); return -EFAULT; } if (image) { if (unlikely(proglen + ilen > oldproglen)) { - pr_err("bpf_jit_compile fatal error\n"); + pr_err("bpf_jit: fatal error\n"); return -EFAULT; } memcpy(image + proglen, temp, ilen); @@ -1085,10 +1085,6 @@ common_load: return proglen; } -void bpf_jit_compile(struct bpf_prog *prog) -{ -} - struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog) { struct bpf_binary_header *header = NULL; diff --git a/include/linux/filter.h b/include/linux/filter.h index e4eb2546339a..c7a70e0cc3a0 100644 --- a/include/linux/filter.h +++ b/include/linux/filter.h @@ -607,6 +607,7 @@ void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp); u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5); struct bpf_prog *bpf_int_jit_compile(struct bpf_prog *prog); +void bpf_jit_compile(struct bpf_prog *prog); bool bpf_helper_changes_pkt_data(void *func); struct bpf_prog *bpf_patch_insn_single(struct bpf_prog *prog, u32 off, @@ -625,7 +626,6 @@ bpf_jit_binary_alloc(unsigned int proglen, u8 **image_ptr, bpf_jit_fill_hole_t bpf_fill_ill_insns); void bpf_jit_binary_free(struct bpf_binary_header *hdr); -void bpf_jit_compile(struct bpf_prog *fp); void bpf_jit_free(struct bpf_prog *fp); struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *fp); @@ -669,10 +669,6 @@ static inline bool bpf_jit_blinding_enabled(void) return true; } #else -static inline void bpf_jit_compile(struct bpf_prog *fp) -{ -} - static inline void bpf_jit_free(struct bpf_prog *fp) { bpf_prog_unlock_free(fp); diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index fddd76b1b627..2831ba1e71c1 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1154,12 +1154,22 @@ const struct bpf_func_proto bpf_tail_call_proto = { .arg3_type = ARG_ANYTHING, }; -/* For classic BPF JITs that don't implement bpf_int_jit_compile(). */ +/* Stub for JITs that only support cBPF. eBPF programs are interpreted. + * It is encouraged to implement bpf_int_jit_compile() instead, so that + * eBPF and implicitly also cBPF can get JITed! + */ struct bpf_prog * __weak bpf_int_jit_compile(struct bpf_prog *prog) { return prog; } +/* Stub for JITs that support eBPF. All cBPF code gets transformed into + * eBPF by the kernel and is later compiled by bpf_int_jit_compile(). + */ +void __weak bpf_jit_compile(struct bpf_prog *prog) +{ +} + bool __weak bpf_helper_changes_pkt_data(void *func) { return false; -- 2.20.1