diff options
| -rw-r--r-- | arch/powerpc/net/bpf_jit64.h | 8 | ||||
| -rw-r--r-- | arch/powerpc/net/bpf_jit_comp64.c | 55 |
2 files changed, 55 insertions, 8 deletions
diff --git a/arch/powerpc/net/bpf_jit64.h b/arch/powerpc/net/bpf_jit64.h index 7b713edfa7e2..b63b35e45e55 100644 --- a/arch/powerpc/net/bpf_jit64.h +++ b/arch/powerpc/net/bpf_jit64.h @@ -16,18 +16,18 @@ * with our redzone usage. * * [ prev sp ] <------------- - * [ nv gpr save area ] 6*8 | + * [ nv gpr save area ] 5*8 | * [ tail_call_cnt ] 8 | - * [ local_tmp_var ] 8 | + * [ local_tmp_var ] 16 | * fp (r31) --> [ ebpf stack space ] upto 512 | * [ frame header ] 32/112 | * sp (r1) ---> [ stack pointer ] -------------- */ /* for gpr non volatile registers BPG_REG_6 to 10 */ -#define BPF_PPC_STACK_SAVE (6*8) +#define BPF_PPC_STACK_SAVE (5*8) /* for bpf JIT code internal usage */ -#define BPF_PPC_STACK_LOCALS 16 +#define BPF_PPC_STACK_LOCALS 24 /* stack frame excluding BPF stack, ensure this is quadword aligned */ #define BPF_PPC_STACKFRAME (STACK_FRAME_MIN_SIZE + \ BPF_PPC_STACK_LOCALS + BPF_PPC_STACK_SAVE) diff --git a/arch/powerpc/net/bpf_jit_comp64.c b/arch/powerpc/net/bpf_jit_comp64.c index 2ea1c3f6e287..8b5157ccfeba 100644 --- a/arch/powerpc/net/bpf_jit_comp64.c +++ b/arch/powerpc/net/bpf_jit_comp64.c @@ -15,6 +15,7 @@ #include <linux/if_vlan.h> #include <asm/kprobes.h> #include <linux/bpf.h> +#include <asm/security_features.h> #include "bpf_jit64.h" @@ -35,9 +36,9 @@ static inline bool bpf_has_stack_frame(struct codegen_context *ctx) * [ prev sp ] <------------- * [ ... ] | * sp (r1) ---> [ stack pointer ] -------------- - * [ nv gpr save area ] 6*8 + * [ nv gpr save area ] 5*8 * [ tail_call_cnt ] 8 - * [ local_tmp_var ] 8 + * [ local_tmp_var ] 16 * [ unused red zone ] 208 bytes protected */ static int bpf_jit_stack_local(struct codegen_context *ctx) @@ -45,12 +46,12 @@ static int bpf_jit_stack_local(struct codegen_context *ctx) if (bpf_has_stack_frame(ctx)) return STACK_FRAME_MIN_SIZE + ctx->stack_size; else - return -(BPF_PPC_STACK_SAVE + 16); + return -(BPF_PPC_STACK_SAVE + 24); } static int bpf_jit_stack_tailcallcnt(struct codegen_context *ctx) { - return bpf_jit_stack_local(ctx) + 8; + return bpf_jit_stack_local(ctx) + 16; } static int bpf_jit_stack_offsetof(struct codegen_context *ctx, int reg) @@ -272,10 +273,33 @@ static int bpf_jit_emit_tail_call(u32 *image, struct codegen_context *ctx, u32 o return 0; } +/* + * We spill into the redzone always, even if the bpf program has its own stackframe. + * Offsets hardcoded based on BPF_PPC_STACK_SAVE -- see bpf_jit_stack_local() + */ +void bpf_stf_barrier(void); + +asm ( +" .global bpf_stf_barrier ;" +" bpf_stf_barrier: ;" +" std 21,-64(1) ;" +" std 22,-56(1) ;" +" sync ;" +" ld 21,-64(1) ;" +" ld 22,-56(1) ;" +" ori 31,31,0 ;" +" .rept 14 ;" +" b 1f ;" +" 1: ;" +" .endr ;" +" blr ;" +); + /* Assemble the body code between the prologue & epilogue */ int bpf_jit_build_body(struct bpf_prog *fp, u32 *image, struct codegen_context *ctx, u32 *addrs, bool extra_pass) { + enum stf_barrier_type stf_barrier = stf_barrier_type_get(); const struct bpf_insn *insn = fp->insnsi; int flen = fp->len; int i, ret; @@ -646,6 +670,29 @@ emit_clear: * BPF_ST NOSPEC (speculation barrier) */ case BPF_ST | BPF_NOSPEC: + if (!security_ftr_enabled(SEC_FTR_FAVOUR_SECURITY) || + !security_ftr_enabled(SEC_FTR_STF_BARRIER)) + break; + + switch (stf_barrier) { + case STF_BARRIER_EIEIO: + EMIT(PPC_RAW_EIEIO() | 0x02000000); + break; + case STF_BARRIER_SYNC_ORI: + EMIT(PPC_RAW_SYNC()); + EMIT(PPC_RAW_LD(b2p[TMP_REG_1], _R13, 0)); + EMIT(PPC_RAW_ORI(_R31, _R31, 0)); + break; + case STF_BARRIER_FALLBACK: + EMIT(PPC_RAW_MFLR(b2p[TMP_REG_1])); + PPC_LI64(12, dereference_kernel_function_descriptor(bpf_stf_barrier)); + EMIT(PPC_RAW_MTCTR(12)); + EMIT(PPC_RAW_BCTRL()); + EMIT(PPC_RAW_MTLR(b2p[TMP_REG_1])); + break; + case STF_BARRIER_NONE: + break; + } break; /* |