diff options
Diffstat (limited to 'arch/arm64/net/bpf_jit_comp.c')
| -rw-r--r-- | arch/arm64/net/bpf_jit_comp.c | 55 |
1 files changed, 28 insertions, 27 deletions
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c index b26da8efa616..145b540ec34f 100644 --- a/arch/arm64/net/bpf_jit_comp.c +++ b/arch/arm64/net/bpf_jit_comp.c @@ -1731,21 +1731,21 @@ static void invoke_bpf_mod_ret(struct jit_ctx *ctx, struct bpf_tramp_links *tl, } } -static void save_args(struct jit_ctx *ctx, int args_off, int nargs) +static void save_args(struct jit_ctx *ctx, int args_off, int nregs) { int i; - for (i = 0; i < nargs; i++) { + for (i = 0; i < nregs; i++) { emit(A64_STR64I(i, A64_SP, args_off), ctx); args_off += 8; } } -static void restore_args(struct jit_ctx *ctx, int args_off, int nargs) +static void restore_args(struct jit_ctx *ctx, int args_off, int nregs) { int i; - for (i = 0; i < nargs; i++) { + for (i = 0; i < nregs; i++) { emit(A64_LDR64I(i, A64_SP, args_off), ctx); args_off += 8; } @@ -1764,7 +1764,7 @@ static void restore_args(struct jit_ctx *ctx, int args_off, int nargs) */ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, struct bpf_tramp_links *tlinks, void *orig_call, - int nargs, u32 flags) + int nregs, u32 flags) { int i; int stack_size; @@ -1772,7 +1772,7 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, int regs_off; int retval_off; int args_off; - int nargs_off; + int nregs_off; int ip_off; int run_ctx_off; struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY]; @@ -1795,11 +1795,11 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, * SP + retval_off [ return value ] BPF_TRAMP_F_CALL_ORIG or * BPF_TRAMP_F_RET_FENTRY_RET * - * [ argN ] + * [ arg reg N ] * [ ... ] - * SP + args_off [ arg1 ] + * SP + args_off [ arg reg 1 ] * - * SP + nargs_off [ args count ] + * SP + nregs_off [ arg regs count ] * * SP + ip_off [ traced function ] BPF_TRAMP_F_IP_ARG flag * @@ -1816,13 +1816,13 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, if (flags & BPF_TRAMP_F_IP_ARG) stack_size += 8; - nargs_off = stack_size; + nregs_off = stack_size; /* room for args count */ stack_size += 8; args_off = stack_size; /* room for args */ - stack_size += nargs * 8; + stack_size += nregs * 8; /* room for return value */ retval_off = stack_size; @@ -1865,12 +1865,12 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, emit(A64_STR64I(A64_R(10), A64_SP, ip_off), ctx); } - /* save args count*/ - emit(A64_MOVZ(1, A64_R(10), nargs, 0), ctx); - emit(A64_STR64I(A64_R(10), A64_SP, nargs_off), ctx); + /* save arg regs count*/ + emit(A64_MOVZ(1, A64_R(10), nregs, 0), ctx); + emit(A64_STR64I(A64_R(10), A64_SP, nregs_off), ctx); - /* save args */ - save_args(ctx, args_off, nargs); + /* save arg regs */ + save_args(ctx, args_off, nregs); /* save callee saved registers */ emit(A64_STR64I(A64_R(19), A64_SP, regs_off), ctx); @@ -1897,7 +1897,7 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, } if (flags & BPF_TRAMP_F_CALL_ORIG) { - restore_args(ctx, args_off, nargs); + restore_args(ctx, args_off, nregs); /* call original func */ emit(A64_LDR64I(A64_R(10), A64_SP, retaddr_off), ctx); emit(A64_ADR(A64_LR, AARCH64_INSN_SIZE * 2), ctx); @@ -1926,7 +1926,7 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im, } if (flags & BPF_TRAMP_F_RESTORE_REGS) - restore_args(ctx, args_off, nargs); + restore_args(ctx, args_off, nregs); /* restore callee saved register x19 and x20 */ emit(A64_LDR64I(A64_R(19), A64_SP, regs_off), ctx); @@ -1967,24 +1967,25 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *orig_call) { int i, ret; - int nargs = m->nr_args; + int nregs = m->nr_args; int max_insns = ((long)image_end - (long)image) / AARCH64_INSN_SIZE; struct jit_ctx ctx = { .image = NULL, .idx = 0, }; - /* the first 8 arguments are passed by registers */ - if (nargs > 8) - return -ENOTSUPP; - - /* don't support struct argument */ + /* extra registers needed for struct argument */ for (i = 0; i < MAX_BPF_FUNC_ARGS; i++) { + /* The arg_size is at most 16 bytes, enforced by the verifier. */ if (m->arg_flags[i] & BTF_FMODEL_STRUCT_ARG) - return -ENOTSUPP; + nregs += (m->arg_size[i] + 7) / 8 - 1; } - ret = prepare_trampoline(&ctx, im, tlinks, orig_call, nargs, flags); + /* the first 8 registers are used for arguments */ + if (nregs > 8) + return -ENOTSUPP; + + ret = prepare_trampoline(&ctx, im, tlinks, orig_call, nregs, flags); if (ret < 0) return ret; @@ -1995,7 +1996,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, ctx.idx = 0; jit_fill_hole(image, (unsigned int)(image_end - image)); - ret = prepare_trampoline(&ctx, im, tlinks, orig_call, nargs, flags); + ret = prepare_trampoline(&ctx, im, tlinks, orig_call, nregs, flags); if (ret > 0 && validate_code(&ctx) < 0) ret = -EINVAL; |