bpf: Remove unused arguments from btf_struct_access().

Remove unused arguments from btf_struct_access() callback.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: David Vernet <void@manifault.com>
Link: https://lore.kernel.org/bpf/20230404045029.82870-3-alexei.starovoitov@gmail.com

include/linux/bpf.h

@@ -893,8 +893,7 @@ struct bpf_verifier_ops {
 				  struct bpf_prog *prog, u32 *target_size);
 	int (*btf_struct_access)(struct bpf_verifier_log *log,
 				 const struct bpf_reg_state *reg,
-				 int off, int size, enum bpf_access_type atype,
-				 u32 *next_btf_id, enum bpf_type_flag *flag);
+				 int off, int size);
 };
 
 struct bpf_prog_offload_ops {

include/linux/filter.h

@@ -571,8 +571,7 @@ DECLARE_STATIC_KEY_FALSE(bpf_stats_enabled_key);
 extern struct mutex nf_conn_btf_access_lock;
 extern int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
 				     const struct bpf_reg_state *reg,
-				     int off, int size, enum bpf_access_type atype,
-				     u32 *next_btf_id, enum bpf_type_flag *flag);
+				     int off, int size);
 
 typedef unsigned int (*bpf_dispatcher_fn)(const void *ctx,
 					  const struct bpf_insn *insnsi,

kernel/bpf/verifier.c

@@ -5459,7 +5459,7 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env,
 	const struct btf_type *t = btf_type_by_id(reg->btf, reg->btf_id);
 	const char *tname = btf_name_by_offset(reg->btf, t->name_off);
 	enum bpf_type_flag flag = 0;
-	u32 btf_id;
+	u32 btf_id = 0;
 	int ret;
 
 	if (!env->allow_ptr_leaks) {
@@ -5509,7 +5509,7 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env,
 			verbose(env, "verifier internal error: reg->btf must be kernel btf\n");
 			return -EFAULT;
 		}
-		ret = env->ops->btf_struct_access(&env->log, reg, off, size, atype, &btf_id, &flag);
+		ret = env->ops->btf_struct_access(&env->log, reg, off, size);
 	} else {
 		/* Writes are permitted with default btf_struct_access for
 		 * program allocated objects (which always have ref_obj_id > 0),

net/bpf/bpf_dummy_struct_ops.c

@@ -173,14 +173,11 @@ static int bpf_dummy_ops_check_member(const struct btf_type *t,
 
 static int bpf_dummy_ops_btf_struct_access(struct bpf_verifier_log *log,
 					   const struct bpf_reg_state *reg,
-					   int off, int size, enum bpf_access_type atype,
-					   u32 *next_btf_id,
-					   enum bpf_type_flag *flag)
+					   int off, int size)
 {
 	const struct btf_type *state;
 	const struct btf_type *t;
 	s32 type_id;
-	int err;
 
 	type_id = btf_find_by_name_kind(reg->btf, "bpf_dummy_ops_state",
 					BTF_KIND_STRUCT);
@@ -194,9 +191,10 @@ static int bpf_dummy_ops_btf_struct_access(struct bpf_verifier_log *log,
 		return -EACCES;
 	}
 
-	err = btf_struct_access(log, reg, off, size, atype, next_btf_id, flag);
-	if (err < 0)
-		return err;
+	if (off + size > sizeof(struct bpf_dummy_ops_state)) {
+		bpf_log(log, "write access at off %d with size %d\n", off, size);
+		return -EACCES;
+	}
 
 	return NOT_INIT;
 }

net/core/filter.c

@@ -8742,20 +8742,18 @@ EXPORT_SYMBOL_GPL(nf_conn_btf_access_lock);
 
 int (*nfct_btf_struct_access)(struct bpf_verifier_log *log,
 			      const struct bpf_reg_state *reg,
-			      int off, int size, enum bpf_access_type atype,
-			      u32 *next_btf_id, enum bpf_type_flag *flag);
+			      int off, int size);
 EXPORT_SYMBOL_GPL(nfct_btf_struct_access);
 
 static int tc_cls_act_btf_struct_access(struct bpf_verifier_log *log,
 					const struct bpf_reg_state *reg,
-					int off, int size, enum bpf_access_type atype,
-					u32 *next_btf_id, enum bpf_type_flag *flag)
+					int off, int size)
 {
 	int ret = -EACCES;
 
 	mutex_lock(&nf_conn_btf_access_lock);
 	if (nfct_btf_struct_access)
-		ret = nfct_btf_struct_access(log, reg, off, size, atype, next_btf_id, flag);
+		ret = nfct_btf_struct_access(log, reg, off, size);
 	mutex_unlock(&nf_conn_btf_access_lock);
 
 	return ret;
@@ -8822,14 +8820,13 @@ EXPORT_SYMBOL_GPL(bpf_warn_invalid_xdp_action);
 
 static int xdp_btf_struct_access(struct bpf_verifier_log *log,
 				 const struct bpf_reg_state *reg,
-				 int off, int size, enum bpf_access_type atype,
-				 u32 *next_btf_id, enum bpf_type_flag *flag)
+				 int off, int size)
 {
 	int ret = -EACCES;
 
 	mutex_lock(&nf_conn_btf_access_lock);
 	if (nfct_btf_struct_access)
-		ret = nfct_btf_struct_access(log, reg, off, size, atype, next_btf_id, flag);
+		ret = nfct_btf_struct_access(log, reg, off, size);
 	mutex_unlock(&nf_conn_btf_access_lock);
 
 	return ret;

net/ipv4/bpf_tcp_ca.c

@@ -72,8 +72,7 @@ static bool bpf_tcp_ca_is_valid_access(int off, int size,
 
 static int bpf_tcp_ca_btf_struct_access(struct bpf_verifier_log *log,
 					const struct bpf_reg_state *reg,
-					int off, int size, enum bpf_access_type atype,
-					u32 *next_btf_id, enum bpf_type_flag *flag)
+					int off, int size)
 {
 	const struct btf_type *t;
 	size_t end;

net/netfilter/nf_conntrack_bpf.c

@@ -192,8 +192,7 @@ BTF_ID(struct, nf_conn___init)
 /* Check writes into `struct nf_conn` */
 static int _nf_conntrack_btf_struct_access(struct bpf_verifier_log *log,
 					   const struct bpf_reg_state *reg,
-					   int off, int size, enum bpf_access_type atype,
-					   u32 *next_btf_id, enum bpf_type_flag *flag)
+					   int off, int size)
 {
 	const struct btf_type *ncit, *nct, *t;
 	size_t end;