This patch migrate fixup_bpf_calls to new list patching
infrastructure.

Signed-off-by: Jiong Wang <jiong.w...@netronome.com>
---
 kernel/bpf/verifier.c | 94 +++++++++++++++++++++++++++------------------------
 1 file changed, 49 insertions(+), 45 deletions(-)

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 2d16e85..30ed28e 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -9033,16 +9033,19 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
 {
        struct bpf_prog *prog = env->prog;
        struct bpf_insn *insn = prog->insnsi;
+       struct bpf_list_insn *list, *elem;
        const struct bpf_func_proto *fn;
-       const int insn_cnt = prog->len;
        const struct bpf_map_ops *ops;
        struct bpf_insn_aux_data *aux;
        struct bpf_insn insn_buf[16];
-       struct bpf_prog *new_prog;
        struct bpf_map *map_ptr;
-       int i, cnt, delta = 0;
+       int cnt, ret = 0;
 
-       for (i = 0; i < insn_cnt; i++, insn++) {
+       list = bpf_create_list_insn(env->prog);
+       if (IS_ERR(list))
+               return PTR_ERR(list);
+       for (elem = list; elem; elem = elem->next) {
+               insn = &elem->insn;
                if (insn->code == (BPF_ALU64 | BPF_MOD | BPF_X) ||
                    insn->code == (BPF_ALU64 | BPF_DIV | BPF_X) ||
                    insn->code == (BPF_ALU | BPF_MOD | BPF_X) ||
@@ -9073,13 +9076,11 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                                cnt = ARRAY_SIZE(mask_and_mod) - (is64 ? 1 : 0);
                        }
 
-                       new_prog = bpf_patch_insn_data(env, i + delta, 
patchlet, cnt);
-                       if (!new_prog)
-                               return -ENOMEM;
-
-                       delta    += cnt - 1;
-                       env->prog = prog = new_prog;
-                       insn      = new_prog->insnsi + i + delta;
+                       elem = bpf_patch_list_insn(elem, patchlet, cnt);
+                       if (IS_ERR(elem)) {
+                               ret = PTR_ERR(elem);
+                               goto free_list_ret;
+                       }
                        continue;
                }
 
@@ -9089,16 +9090,15 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                        cnt = env->ops->gen_ld_abs(insn, insn_buf);
                        if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
                                verbose(env, "bpf verifier is misconfigured\n");
-                               return -EINVAL;
+                               ret = -EINVAL;
+                               goto free_list_ret;
                        }
 
-                       new_prog = bpf_patch_insn_data(env, i + delta, 
insn_buf, cnt);
-                       if (!new_prog)
-                               return -ENOMEM;
-
-                       delta    += cnt - 1;
-                       env->prog = prog = new_prog;
-                       insn      = new_prog->insnsi + i + delta;
+                       elem = bpf_patch_list_insn(elem, insn_buf, cnt);
+                       if (IS_ERR(elem)) {
+                               ret = PTR_ERR(elem);
+                               goto free_list_ret;
+                       }
                        continue;
                }
 
@@ -9111,7 +9111,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                        bool issrc, isneg;
                        u32 off_reg;
 
-                       aux = &env->insn_aux_data[i + delta];
+                       aux = &env->insn_aux_data[elem->orig_idx - 1];
                        if (!aux->alu_state ||
                            aux->alu_state == BPF_ALU_NON_POINTER)
                                continue;
@@ -9144,13 +9144,12 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                                *patch++ = BPF_ALU64_IMM(BPF_MUL, off_reg, -1);
                        cnt = patch - insn_buf;
 
-                       new_prog = bpf_patch_insn_data(env, i + delta, 
insn_buf, cnt);
-                       if (!new_prog)
-                               return -ENOMEM;
+                       elem = bpf_patch_list_insn(elem, insn_buf, cnt);
+                       if (IS_ERR(elem)) {
+                               ret = PTR_ERR(elem);
+                               goto free_list_ret;
+                       }
 
-                       delta    += cnt - 1;
-                       env->prog = prog = new_prog;
-                       insn      = new_prog->insnsi + i + delta;
                        continue;
                }
 
@@ -9183,7 +9182,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                        insn->imm = 0;
                        insn->code = BPF_JMP | BPF_TAIL_CALL;
 
-                       aux = &env->insn_aux_data[i + delta];
+                       aux = &env->insn_aux_data[elem->orig_idx - 1];
                        if (!bpf_map_ptr_unpriv(aux))
                                continue;
 
@@ -9195,7 +9194,8 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                         */
                        if (bpf_map_ptr_poisoned(aux)) {
                                verbose(env, "tail_call abusing map_ptr\n");
-                               return -EINVAL;
+                               ret = -EINVAL;
+                               goto free_list_ret;
                        }
 
                        map_ptr = BPF_MAP_PTR(aux->map_state);
@@ -9207,13 +9207,12 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                                                                 
map)->index_mask);
                        insn_buf[2] = *insn;
                        cnt = 3;
-                       new_prog = bpf_patch_insn_data(env, i + delta, 
insn_buf, cnt);
-                       if (!new_prog)
-                               return -ENOMEM;
+                       elem = bpf_patch_list_insn(elem, insn_buf, cnt);
+                       if (IS_ERR(elem)) {
+                               ret = PTR_ERR(elem);
+                               goto free_list_ret;
+                       }
 
-                       delta    += cnt - 1;
-                       env->prog = prog = new_prog;
-                       insn      = new_prog->insnsi + i + delta;
                        continue;
                }
 
@@ -9228,7 +9227,7 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                     insn->imm == BPF_FUNC_map_push_elem   ||
                     insn->imm == BPF_FUNC_map_pop_elem    ||
                     insn->imm == BPF_FUNC_map_peek_elem)) {
-                       aux = &env->insn_aux_data[i + delta];
+                       aux = &env->insn_aux_data[elem->orig_idx - 1];
                        if (bpf_map_ptr_poisoned(aux))
                                goto patch_call_imm;
 
@@ -9239,17 +9238,16 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                                cnt = ops->map_gen_lookup(map_ptr, insn_buf);
                                if (cnt == 0 || cnt >= ARRAY_SIZE(insn_buf)) {
                                        verbose(env, "bpf verifier is 
misconfigured\n");
-                                       return -EINVAL;
+                                       ret = -EINVAL;
+                                       goto free_list_ret;
                                }
 
-                               new_prog = bpf_patch_insn_data(env, i + delta,
-                                                              insn_buf, cnt);
-                               if (!new_prog)
-                                       return -ENOMEM;
+                               elem = bpf_patch_list_insn(elem, insn_buf, cnt);
+                               if (IS_ERR(elem)) {
+                                       ret = PTR_ERR(elem);
+                                       goto free_list_ret;
+                               }
 
-                               delta    += cnt - 1;
-                               env->prog = prog = new_prog;
-                               insn      = new_prog->insnsi + i + delta;
                                continue;
                        }
 
@@ -9307,12 +9305,18 @@ static int fixup_bpf_calls(struct bpf_verifier_env *env)
                        verbose(env,
                                "kernel subsystem misconfigured func %s#%d\n",
                                func_id_name(insn->imm), insn->imm);
-                       return -EFAULT;
+                       ret = -EFAULT;
+                       goto free_list_ret;
                }
                insn->imm = fn->func - __bpf_call_base;
        }
 
-       return 0;
+       env = verifier_linearize_list_insn(env, list);
+       if (IS_ERR(env))
+               ret = PTR_ERR(env);
+free_list_ret:
+       bpf_destroy_list_insn(list);
+       return ret;
 }
 
 static void free_states(struct bpf_verifier_env *env)
-- 
2.7.4

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