bpf: move fixup_bpf_calls() function

no functional change.
move fixup_bpf_calls() to verifier.c
it's being refactored in the next patch

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 57 insertions, 56 deletions

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 7af0dcc5d755..48c914b983bd 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -586,59 +586,6 @@ void bpf_register_prog_type(struct bpf_prog_type_list *tl)
         list_add(&tl->list_node, &bpf_prog_types);
 }
 
-/* fixup insn->imm field of bpf_call instructions:
- * if (insn->imm == BPF_FUNC_map_lookup_elem)
- *      insn->imm = bpf_map_lookup_elem - __bpf_call_base;
- * else if (insn->imm == BPF_FUNC_map_update_elem)
- *      insn->imm = bpf_map_update_elem - __bpf_call_base;
- * else ...
- *
- * this function is called after eBPF program passed verification
- */
-static void fixup_bpf_calls(struct bpf_prog *prog)
-{
-        const struct bpf_func_proto *fn;
-        int i;
-
-        for (i = 0; i < prog->len; i++) {
-                struct bpf_insn *insn = &prog->insnsi[i];
-
-                if (insn->code == (BPF_JMP | BPF_CALL)) {
-                        /* we reach here when program has bpf_call instructions
-                         * and it passed bpf_check(), means that
-                         * ops->get_func_proto must have been supplied, check it
-                         */
-                        BUG_ON(!prog->aux->ops->get_func_proto);
-
-                        if (insn->imm == BPF_FUNC_get_route_realm)
-                                prog->dst_needed = 1;
-                        if (insn->imm == BPF_FUNC_get_prandom_u32)
-                                bpf_user_rnd_init_once();
-                        if (insn->imm == BPF_FUNC_xdp_adjust_head)
-                                prog->xdp_adjust_head = 1;
-                        if (insn->imm == BPF_FUNC_tail_call) {
-                                /* mark bpf_tail_call as different opcode
-                                 * to avoid conditional branch in
-                                 * interpeter for every normal call
-                                 * and to prevent accidental JITing by
-                                 * JIT compiler that doesn't support
-                                 * bpf_tail_call yet
-                                 */
-                                insn->imm = 0;
-                                insn->code |= BPF_X;
-                                continue;
-                        }
-
-                        fn = prog->aux->ops->get_func_proto(insn->imm);
-                        /* all functions that have prototype and verifier allowed
-                         * programs to call them, must be real in-kernel functions
-                         */
-                        BUG_ON(!fn->func);
-                        insn->imm = fn->func - __bpf_call_base;
-                }
-        }
-}
-
 /* drop refcnt on maps used by eBPF program and free auxilary data */
 static void free_used_maps(struct bpf_prog_aux *aux)
 {
@@ -892,9 +839,6 @@ static int bpf_prog_load(union bpf_attr *attr)
         if (err < 0)
                 goto free_used_maps;
 
-        /* fixup BPF_CALL->imm field */
-        fixup_bpf_calls(prog);
-
         /* eBPF program is ready to be JITed */
         prog = bpf_prog_select_runtime(prog, &err);
         if (err < 0)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 796b68d00119..e41da6c57053 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -3233,6 +3233,60 @@ static int convert_ctx_accesses(struct bpf_verifier_env *env)
         return 0;
 }
 
+/* fixup insn->imm field of bpf_call instructions:
+ * if (insn->imm == BPF_FUNC_map_lookup_elem)
+ *      insn->imm = bpf_map_lookup_elem - __bpf_call_base;
+ * else if (insn->imm == BPF_FUNC_map_update_elem)
+ *      insn->imm = bpf_map_update_elem - __bpf_call_base;
+ * else ...
+ *
+ * this function is called after eBPF program passed verification
+ */
+static void fixup_bpf_calls(struct bpf_prog *prog)
+{
+        const struct bpf_func_proto *fn;
+        int i;
+
+        for (i = 0; i < prog->len; i++) {
+                struct bpf_insn *insn = &prog->insnsi[i];
+
+                if (insn->code == (BPF_JMP | BPF_CALL)) {
+                        /* we reach here when program has bpf_call instructions
+                         * and it passed bpf_check(), means that
+                         * ops->get_func_proto must have been supplied, check it
+                         */
+                        BUG_ON(!prog->aux->ops->get_func_proto);
+
+                        if (insn->imm == BPF_FUNC_get_route_realm)
+                                prog->dst_needed = 1;
+                        if (insn->imm == BPF_FUNC_get_prandom_u32)
+                                bpf_user_rnd_init_once();
+                        if (insn->imm == BPF_FUNC_xdp_adjust_head)
+                                prog->xdp_adjust_head = 1;
+                        if (insn->imm == BPF_FUNC_tail_call) {
+                                /* mark bpf_tail_call as different opcode
+                                 * to avoid conditional branch in
+                                 * interpeter for every normal call
+                                 * and to prevent accidental JITing by
+                                 * JIT compiler that doesn't support
+                                 * bpf_tail_call yet
+                                 */
+                                insn->imm = 0;
+                                insn->code |= BPF_X;
+                                continue;
+                        }
+
+                        fn = prog->aux->ops->get_func_proto(insn->imm);
+                        /* all functions that have prototype and verifier allowed
+                         * programs to call them, must be real in-kernel functions
+                         */
+                        BUG_ON(!fn->func);
+                        insn->imm = fn->func - __bpf_call_base;
+                }
+        }
+}
+
+
 static void free_states(struct bpf_verifier_env *env)
 {
         struct bpf_verifier_state_list *sl, *sln;
@@ -3328,6 +3382,9 @@ skip_full_check:
                 /* program is valid, convert *(u32*)(ctx + off) accesses */
                 ret = convert_ctx_accesses(env);
 
+        if (ret == 0)
+                fixup_bpf_calls(env->prog);
+
         if (log_level && log_len >= log_size - 1) {
                 BUG_ON(log_len >= log_size);
                 /* verifier log exceeded user supplied buffer */