Commit 6f55b2f2 authored by Daniel Borkmann's avatar Daniel Borkmann
Browse files

bpf: Move off_reg into sanitize_ptr_alu 



Small refactor to drag off_reg into sanitize_ptr_alu(), so we later on can
use off_reg for generalizing some of the checks for all pointer types.

Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Reviewed-by: default avatarJohn Fastabend <john.fastabend@gmail.com>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 96011483

kernel/bpf/verifier.c

+5 −4
Original line number Diff line number Diff line
@@ -5929,11 +5929,12 @@ static int sanitize_val_alu(struct bpf_verifier_env *env, 
static int sanitize_ptr_alu(struct bpf_verifier_env *env,

			    struct bpf_insn *insn,

			    const struct bpf_reg_state *ptr_reg,

			    struct bpf_reg_state *dst_reg,

			    bool off_is_neg)

			    const struct bpf_reg_state *off_reg,

			    struct bpf_reg_state *dst_reg)

{

	struct bpf_verifier_state *vstate = env->cur_state;

	struct bpf_insn_aux_data *aux = cur_aux(env);

	bool off_is_neg = off_reg->smin_value < 0;

	bool ptr_is_dst_reg = ptr_reg == dst_reg;

	u8 opcode = BPF_OP(insn->code);

	u32 alu_state, alu_limit;
@@ -6110,7 +6111,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, 


	switch (opcode) {

	case BPF_ADD:

		ret = sanitize_ptr_alu(env, insn, ptr_reg, dst_reg, smin_val < 0);

		ret = sanitize_ptr_alu(env, insn, ptr_reg, off_reg, dst_reg);

		if (ret < 0) {

			verbose(env, "R%d tried to add from different maps, paths, or prohibited types\n", dst);

			return ret;
@@ -6165,7 +6166,7 @@ static int adjust_ptr_min_max_vals(struct bpf_verifier_env *env, 
		}

		break;

	case BPF_SUB:

		ret = sanitize_ptr_alu(env, insn, ptr_reg, dst_reg, smin_val < 0);

		ret = sanitize_ptr_alu(env, insn, ptr_reg, off_reg, dst_reg);

		if (ret < 0) {

			verbose(env, "R%d tried to sub from different maps, paths, or prohibited types\n", dst);

			return ret;