bpf: Move BPF_STX reserved field check into BPF_STX verifier code

I can't find a reason why this code is in resolve_pseudo_ldimm64;
since I'll be modifying it in a subsequent commit, tidy it up.

Signed-off-by: Brendan Jackman <jackmanb@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210114181751.768687-6-jackmanb@google.com

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index cfc137b81ac6661adaa492d982f80eb146fda73a..d8a85f4e5b95058e328d558ca321f13aedf704b0 100644 (file)
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -9528,6 +9528,12 @@ static int do_check(struct bpf_verifier_env *env)
                } else if (class == BPF_STX) {
                        enum bpf_reg_type *prev_dst_type, dst_reg_type;
 
+                       if (((BPF_MODE(insn->code) != BPF_MEM &&
+                             BPF_MODE(insn->code) != BPF_ATOMIC) || insn->imm != 0)) {
+                               verbose(env, "BPF_STX uses reserved fields\n");
+                               return -EINVAL;
+                       }
+
                        if (BPF_MODE(insn->code) == BPF_ATOMIC) {
                                err = check_atomic(env, env->insn_idx, insn);
                                if (err)
@@ -10012,13 +10018,6 @@ static int resolve_pseudo_ldimm64(struct bpf_verifier_env *env)
                        return -EINVAL;
                }
 
-               if (BPF_CLASS(insn->code) == BPF_STX &&
-                   ((BPF_MODE(insn->code) != BPF_MEM &&
-                     BPF_MODE(insn->code) != BPF_ATOMIC) || insn->imm != 0)) {
-                       verbose(env, "BPF_STX uses reserved fields\n");
-                       return -EINVAL;
-               }
-
                if (insn[0].code == (BPF_LD | BPF_IMM | BPF_DW)) {
                        struct bpf_insn_aux_data *aux;
                        struct bpf_map *map;