bpf: emit more dynptr information in verifier log

Emit dynptr type for CONST_PTR_TO_DYNPTR register. Also emit id,
ref_obj_id, and dynptr_id fields for STACK_DYNPTR stack slots.

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20231204233931.49758-3-andrii@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/kernel/bpf/log.c b/kernel/bpf/log.c
index 61d7d23a011854ac95ae9a25c8a515410f0ee167..594a234f122bbb5ed569445cd8dbb9bc75a0b3ab 100644 (file)
--- a/kernel/bpf/log.c
+++ b/kernel/bpf/log.c
@@ -628,6 +628,12 @@ static bool type_is_map_ptr(enum bpf_reg_type t) {
        }
 }
 
+/*
+ * _a stands for append, was shortened to avoid multiline statements below.
+ * This macro is used to output a comma separated list of attributes.
+ */
+#define verbose_a(fmt, ...) ({ verbose(env, "%s" fmt, sep, ##__VA_ARGS__); sep = ","; })
+
 static void print_reg_state(struct bpf_verifier_env *env,
                            const struct bpf_func_state *state,
                            const struct bpf_reg_state *reg)
@@ -643,11 +649,6 @@ static void print_reg_state(struct bpf_verifier_env *env,
                verbose_snum(env, reg->var_off.value + reg->off);
                return;
        }
-/*
- * _a stands for append, was shortened to avoid multiline statements below.
- * This macro is used to output a comma separated list of attributes.
- */
-#define verbose_a(fmt, ...) ({ verbose(env, "%s" fmt, sep, ##__VA_ARGS__); sep = ","; })
 
        verbose(env, "%s", reg_type_str(env, t));
        if (t == PTR_TO_STACK) {
@@ -686,6 +687,8 @@ static void print_reg_state(struct bpf_verifier_env *env,
                verbose_a("sz=");
                verbose_unum(env, reg->mem_size);
        }
+       if (t == CONST_PTR_TO_DYNPTR)
+               verbose_a("type=%s",  dynptr_type_str(reg->dynptr.type));
        if (tnum_is_const(reg->var_off)) {
                /* a pointer register with fixed offset */
                if (reg->var_off.value) {
@@ -702,8 +705,6 @@ static void print_reg_state(struct bpf_verifier_env *env,
                }
        }
        verbose(env, ")");
-
-#undef verbose_a
 }
 
 void print_verifier_state(struct bpf_verifier_env *env, const struct bpf_func_state *state,
@@ -727,6 +728,7 @@ void print_verifier_state(struct bpf_verifier_env *env, const struct bpf_func_st
        }
        for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
                char types_buf[BPF_REG_SIZE + 1];
+               const char *sep = "";
                bool valid = false;
                u8 slot_type;
                int j;
@@ -765,9 +767,14 @@ void print_verifier_state(struct bpf_verifier_env *env, const struct bpf_func_st
 
                        verbose(env, " fp%d", (-i - 1) * BPF_REG_SIZE);
                        print_liveness(env, reg->live);
-                       verbose(env, "=dynptr_%s", dynptr_type_str(reg->dynptr.type));
+                       verbose(env, "=dynptr_%s(", dynptr_type_str(reg->dynptr.type));
+                       if (reg->id)
+                               verbose_a("id=%d", reg->id);
                        if (reg->ref_obj_id)
-                               verbose(env, "(ref_id=%d)", reg->ref_obj_id);
+                               verbose_a("ref_id=%d", reg->ref_obj_id);
+                       if (reg->dynptr_id)
+                               verbose_a("dynptr_id=%d", reg->dynptr_id);
+                       verbose(env, ")");
                        break;
                case STACK_ITER:
                        /* only main slot has ref_obj_id set; skip others */