Commit dcb2288b authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
Browse files

bpf: Remove unused insn_cnt argument from visit_[func_call_]insn() 



Number of total instructions in BPF program (including subprogs) can and
is accessed from env->prog->len. visit_func_call_insn() doesn't do any
checks against insn_cnt anymore, relying on push_insn() to do this check
internally. So remove unnecessary insn_cnt input argument from
visit_func_call_insn() and visit_insn() functions.

Suggested-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarAndrii Nakryiko <andrii@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20221207195534.2866030-1-andrii@kernel.org
parent 0a6ea1ce

kernel/bpf/verifier.c

+5 −6
Original line number Diff line number Diff line
@@ -12222,8 +12222,7 @@ static int push_insn(int t, int w, int e, struct bpf_verifier_env *env, 
	return DONE_EXPLORING;

}



static int visit_func_call_insn(int t, int insn_cnt,

				struct bpf_insn *insns,

static int visit_func_call_insn(int t, struct bpf_insn *insns,

				struct bpf_verifier_env *env,

				bool visit_callee)

{
@@ -12254,13 +12253,13 @@ static int visit_func_call_insn(int t, int insn_cnt, 
 *  DONE_EXPLORING - the instruction was fully explored

 *  KEEP_EXPLORING - there is still work to be done before it is fully explored

 */

static int visit_insn(int t, int insn_cnt, struct bpf_verifier_env *env)

static int visit_insn(int t, struct bpf_verifier_env *env)

{

	struct bpf_insn *insns = env->prog->insnsi;

	int ret;



	if (bpf_pseudo_func(insns + t))

		return visit_func_call_insn(t, insn_cnt, insns, env, true);

		return visit_func_call_insn(t, insns, env, true);



	/* All non-branch instructions have a single fall-through edge. */

	if (BPF_CLASS(insns[t].code) != BPF_JMP &&
@@ -12279,7 +12278,7 @@ static int visit_insn(int t, int insn_cnt, struct bpf_verifier_env *env) 
			 * async state will be pushed for further exploration.

			 */

			mark_prune_point(env, t);

		return visit_func_call_insn(t, insn_cnt, insns, env,

		return visit_func_call_insn(t, insns, env,

					    insns[t].src_reg == BPF_PSEUDO_CALL);



	case BPF_JA:
@@ -12336,7 +12335,7 @@ static int check_cfg(struct bpf_verifier_env *env) 
	while (env->cfg.cur_stack > 0) {

		int t = insn_stack[env->cfg.cur_stack - 1];



		ret = visit_insn(t, insn_cnt, env);

		ret = visit_insn(t, env);

		switch (ret) {

		case DONE_EXPLORING:

			insn_state[t] = EXPLORED;