Commit b32a5dae authored by Dave Marchevsky's avatar Dave Marchevsky Committed by Alexei Starovoitov
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bpf: verifier: Rename kernel_type_name helper to btf_type_name 



kernel_type_name was introduced in commit 9e15db66 ("bpf: Implement accurate raw_tp context access via BTF")
with type signature:

  const char *kernel_type_name(u32 id)

At that time the function used global btf_vmlinux BTF for all id lookups. Later,
in commit 22dc4a0f ("bpf: Remove hard-coded btf_vmlinux assumption from BPF verifier"),
the type signature was changed to:

  static const char *kernel_type_name(const struct btf* btf, u32 id)

With the btf parameter used for lookups instead of global btf_vmlinux.

The helper will function as expected for type name lookup using non-kernel BTFs,
and will be used for such in further patches in the series. Let's rename it to
avoid incorrect assumptions that might arise when seeing the current name.

Signed-off-by: default avatarDave Marchevsky <davemarchevsky@fb.com>
Link: https://lore.kernel.org/r/20230309180111.1618459-2-davemarchevsky@fb.com


Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 4659fba1

kernel/bpf/verifier.c

+8 −8
Original line number Diff line number Diff line
@@ -752,7 +752,7 @@ static int iter_get_spi(struct bpf_verifier_env *env, struct bpf_reg_state *reg, 
	return stack_slot_obj_get_spi(env, reg, "iter", nr_slots);

}









static const char *kernel_type_name(const struct btf* btf, u32 id)









static const char *btf_type_name(const struct btf *btf, u32 id)









{









	return btf_name_by_offset(btf, btf_type_by_id(btf, id)->name_off);









}








@@ -782,7 +782,7 @@ static const char *iter_type_str(const struct btf *btf, u32 btf_id)







		return "<invalid>";

















	/* we already validated that type is valid and has conforming name */









	return kernel_type_name(btf, btf_id) + sizeof(ITER_PREFIX) - 1;









	return btf_type_name(btf, btf_id) + sizeof(ITER_PREFIX) - 1;









}

















static const char *iter_state_str(enum bpf_iter_state state)








@@ -1349,7 +1349,7 @@ static void print_verifier_state(struct bpf_verifier_env *env,















			verbose(env, "%s", reg_type_str(env, t));









			if (base_type(t) == PTR_TO_BTF_ID)









				verbose(env, "%s", kernel_type_name(reg->btf, reg->btf_id));









				verbose(env, "%s", btf_type_name(reg->btf, reg->btf_id));









			verbose(env, "(");









/*









 * _a stands for append, was shortened to avoid multiline statements below.








@@ -4518,7 +4518,7 @@ static int map_kptr_match_type(struct bpf_verifier_env *env,







			       struct btf_field *kptr_field,









			       struct bpf_reg_state *reg, u32 regno)









{









	const char *targ_name = kernel_type_name(kptr_field->kptr.btf, kptr_field->kptr.btf_id);









	const char *targ_name = btf_type_name(kptr_field->kptr.btf, kptr_field->kptr.btf_id);









	int perm_flags = PTR_MAYBE_NULL | PTR_TRUSTED | MEM_RCU;









	const char *reg_name = "";
















@@ -4534,7 +4534,7 @@ static int map_kptr_match_type(struct bpf_verifier_env *env,







		return -EINVAL;









	}









	/* We need to verify reg->type and reg->btf, before accessing reg->btf */









	reg_name = kernel_type_name(reg->btf, reg->btf_id);









	reg_name = btf_type_name(reg->btf, reg->btf_id);

















	/* For ref_ptr case, release function check should ensure we get one









	 * referenced PTR_TO_BTF_ID, and that its fixed offset is 0. For the








@@ -7177,8 +7177,8 @@ static int check_reg_type(struct bpf_verifier_env *env, u32 regno,







						  btf_vmlinux, *arg_btf_id,









						  strict_type_match)) {









				verbose(env, "R%d is of type %s but %s is expected\n",









					regno, kernel_type_name(reg->btf, reg->btf_id),









					kernel_type_name(btf_vmlinux, *arg_btf_id));









					regno, btf_type_name(reg->btf, reg->btf_id),









					btf_type_name(btf_vmlinux, *arg_btf_id));









				return -EACCES;









			}









		}








@@ -7248,7 +7248,7 @@ int check_func_arg_reg_off(struct bpf_verifier_env *env,







			verbose(env, "R%d must have zero offset when passed to release func\n",









				regno);









			verbose(env, "No graph node or root found at R%d type:%s off:%d\n", regno,









				kernel_type_name(reg->btf, reg->btf_id), reg->off);









				btf_type_name(reg->btf, reg->btf_id), reg->off);









			return -EINVAL;









		}