diff options
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/core.c | 13 | ||||
| -rw-r--r-- | kernel/bpf/syscall.c | 3 | ||||
| -rw-r--r-- | kernel/bpf/verifier.c | 126 |
3 files changed, 139 insertions, 3 deletions
diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index bda911644b1c..768e0a02d8c8 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -722,7 +722,7 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) struct bpf_insn *insn; int i, rewritten; - if (!bpf_jit_blinding_enabled(prog)) + if (!bpf_jit_blinding_enabled(prog) || prog->blinded) return prog; clone = bpf_prog_clone_create(prog, GFP_USER); @@ -764,6 +764,7 @@ struct bpf_prog *bpf_jit_blind_constants(struct bpf_prog *prog) i += insn_delta; } + clone->blinded = 1; return clone; } #endif /* CONFIG_BPF_JIT */ @@ -1629,11 +1630,19 @@ int bpf_prog_array_copy_info(struct bpf_prog_array __rcu *array, static void bpf_prog_free_deferred(struct work_struct *work) { struct bpf_prog_aux *aux; + int i; aux = container_of(work, struct bpf_prog_aux, work); if (bpf_prog_is_dev_bound(aux)) bpf_prog_offload_destroy(aux->prog); - bpf_jit_free(aux->prog); + for (i = 0; i < aux->func_cnt; i++) + bpf_jit_free(aux->func[i]); + if (aux->func_cnt) { + kfree(aux->func); + bpf_prog_unlock_free(aux->prog); + } else { + bpf_jit_free(aux->prog); + } } /* Free internal BPF program */ diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index 2c4cfeaa8d5e..e2e1c78ce1dc 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -1194,7 +1194,8 @@ static int bpf_prog_load(union bpf_attr *attr) goto free_used_maps; /* eBPF program is ready to be JITed */ - prog = bpf_prog_select_runtime(prog, &err); + if (!prog->bpf_func) + prog = bpf_prog_select_runtime(prog, &err); if (err < 0) goto free_used_maps; diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 8e0e4cd0d5e4..48b2901cf483 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -5012,12 +5012,138 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env) return 0; } +static int jit_subprogs(struct bpf_verifier_env *env) +{ + struct bpf_prog *prog = env->prog, **func, *tmp; + int i, j, subprog_start, subprog_end = 0, len, subprog; + struct bpf_insn *insn = prog->insnsi; + void *old_bpf_func; + int err = -ENOMEM; + + if (env->subprog_cnt == 0) + return 0; + + for (i = 0; i < prog->len; i++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + subprog = find_subprog(env, i + insn->imm + 1); + if (subprog < 0) { + WARN_ONCE(1, "verifier bug. No program starts at insn %d\n", + i + insn->imm + 1); + return -EFAULT; + } + /* temporarily remember subprog id inside insn instead of + * aux_data, since next loop will split up all insns into funcs + */ + insn->off = subprog + 1; + /* remember original imm in case JIT fails and fallback + * to interpreter will be needed + */ + env->insn_aux_data[i].call_imm = insn->imm; + /* point imm to __bpf_call_base+1 from JITs point of view */ + insn->imm = 1; + } + + func = kzalloc(sizeof(prog) * (env->subprog_cnt + 1), GFP_KERNEL); + if (!func) + return -ENOMEM; + + for (i = 0; i <= env->subprog_cnt; i++) { + subprog_start = subprog_end; + if (env->subprog_cnt == i) + subprog_end = prog->len; + else + subprog_end = env->subprog_starts[i]; + + len = subprog_end - subprog_start; + func[i] = bpf_prog_alloc(bpf_prog_size(len), GFP_USER); + if (!func[i]) + goto out_free; + memcpy(func[i]->insnsi, &prog->insnsi[subprog_start], + len * sizeof(struct bpf_insn)); + func[i]->len = len; + func[i]->is_func = 1; + /* Use bpf_prog_F_tag to indicate functions in stack traces. + * Long term would need debug info to populate names + */ + func[i]->aux->name[0] = 'F'; + func[i]->aux->stack_depth = env->subprog_stack_depth[i]; + func[i]->jit_requested = 1; + func[i] = bpf_int_jit_compile(func[i]); + if (!func[i]->jited) { + err = -ENOTSUPP; + goto out_free; + } + cond_resched(); + } + /* at this point all bpf functions were successfully JITed + * now populate all bpf_calls with correct addresses and + * run last pass of JIT + */ + for (i = 0; i <= env->subprog_cnt; i++) { + insn = func[i]->insnsi; + for (j = 0; j < func[i]->len; j++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + subprog = insn->off; + insn->off = 0; + insn->imm = (u64 (*)(u64, u64, u64, u64, u64)) + func[subprog]->bpf_func - + __bpf_call_base; + } + } + for (i = 0; i <= env->subprog_cnt; i++) { + old_bpf_func = func[i]->bpf_func; + tmp = bpf_int_jit_compile(func[i]); + if (tmp != func[i] || func[i]->bpf_func != old_bpf_func) { + verbose(env, "JIT doesn't support bpf-to-bpf calls\n"); + err = -EFAULT; + goto out_free; + } + cond_resched(); + } + + /* finally lock prog and jit images for all functions and + * populate kallsysm + */ + for (i = 0; i <= env->subprog_cnt; i++) { + bpf_prog_lock_ro(func[i]); + bpf_prog_kallsyms_add(func[i]); + } + prog->jited = 1; + prog->bpf_func = func[0]->bpf_func; + prog->aux->func = func; + prog->aux->func_cnt = env->subprog_cnt + 1; + return 0; +out_free: + for (i = 0; i <= env->subprog_cnt; i++) + if (func[i]) + bpf_jit_free(func[i]); + kfree(func); + /* cleanup main prog to be interpreted */ + prog->jit_requested = 0; + for (i = 0, insn = prog->insnsi; i < prog->len; i++, insn++) { + if (insn->code != (BPF_JMP | BPF_CALL) || + insn->src_reg != BPF_PSEUDO_CALL) + continue; + insn->off = 0; + insn->imm = env->insn_aux_data[i].call_imm; + } + return err; +} + static int fixup_call_args(struct bpf_verifier_env *env) { struct bpf_prog *prog = env->prog; struct bpf_insn *insn = prog->insnsi; int i, depth; + if (env->prog->jit_requested) + if (jit_subprogs(env) == 0) + return 0; + for (i = 0; i < prog->len; i++, insn++) { if (insn->code != (BPF_JMP | BPF_CALL) || insn->src_reg != BPF_PSEUDO_CALL) |