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Drop the check in is_kfunc_arg_mem_size() and is_kfunc_arg_const_mem_size() to further decouple get_kfunc_ptr_arg_type() from register state (a prerequisite for generating a helper-like prototype from kfunc's BTF). Signed-off-by: Amery Hung --- kernel/bpf/verifier.c | 20 +++++++++----------- 1 file changed, 9 insertions(+), 11 deletions(-) diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 0f8d40308317..f6b373630ca9 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -10795,26 +10795,24 @@ static bool is_kfunc_rcu_protected(struct bpf_call_arg_meta *meta) } static bool is_kfunc_arg_mem_size(const struct btf *btf, - const struct btf_param *arg, - const struct bpf_reg_state *reg) + const struct btf_param *arg) { const struct btf_type *t; t = btf_type_skip_modifiers(btf, arg->type, NULL); - if (!btf_type_is_scalar(t) || reg->type != SCALAR_VALUE) + if (!btf_type_is_scalar(t)) return false; return btf_param_match_suffix(btf, arg, "__sz"); } static bool is_kfunc_arg_const_mem_size(const struct btf *btf, - const struct btf_param *arg, - const struct bpf_reg_state *reg) + const struct btf_param *arg) { const struct btf_type *t; t = btf_type_skip_modifiers(btf, arg->type, NULL); - if (!btf_type_is_scalar(t) || reg->type != SCALAR_VALUE) + if (!btf_type_is_scalar(t)) return false; return btf_param_match_suffix(btf, arg, "__szk"); @@ -11348,7 +11346,7 @@ bool bpf_is_kfunc_pkt_changing(struct bpf_call_arg_meta *meta) } static enum kfunc_ptr_arg_type -get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, struct bpf_func_state *caller, +get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, struct bpf_reg_state *regs, struct bpf_call_arg_meta *meta, const struct btf_type *t, const struct btf_type *ref_t, const char *ref_tname, const struct btf_param *args, @@ -11362,8 +11360,8 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, struct bpf_func_state *call return KF_ARG_PTR_TO_CTX; if (arg + 1 < nargs && - (is_kfunc_arg_mem_size(meta->btf, &args[arg + 1], get_func_arg_reg(caller, regs, arg + 1)) || - is_kfunc_arg_const_mem_size(meta->btf, &args[arg + 1], get_func_arg_reg(caller, regs, arg + 1)))) + (is_kfunc_arg_mem_size(meta->btf, &args[arg + 1]) || + is_kfunc_arg_const_mem_size(meta->btf, &args[arg + 1]))) arg_mem_size = true; /* In this function, we verify the kfunc's BTF as per the argument type, @@ -12094,7 +12092,7 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_call_arg_me } if (is_kfunc_arg_constant(meta->btf, &args[i]) || - is_kfunc_arg_const_mem_size(meta->btf, &args[i], reg)) { + is_kfunc_arg_const_mem_size(meta->btf, &args[i])) { ret = process_const_arg(env, reg, argno, meta); if (ret < 0) return ret; @@ -12139,7 +12137,7 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_call_arg_me ref_t = btf_type_skip_modifiers(btf, t->type, &ref_id); ref_tname = btf_name_by_offset(btf, ref_t->name_off); - kf_arg_type = get_kfunc_ptr_arg_type(env, caller, regs, meta, t, ref_t, ref_tname, + kf_arg_type = get_kfunc_ptr_arg_type(env, regs, meta, t, ref_t, ref_tname, args, i, nargs, argno, reg); if (kf_arg_type < 0) return kf_arg_type; -- 2.52.0