Commit b65ce380 authored by Cong Wang's avatar Cong Wang Committed by David S. Miller
Browse files

genetlink: clean up family attributes allocations 



genl_family_rcv_msg_attrs_parse() and genl_family_rcv_msg_attrs_free()
take a boolean parameter to determine whether allocate/free the family
attrs. This is unnecessary as we can just check family->parallel_ops.
More importantly, callers would not need to worry about pairing these
parameters correctly after this patch.

And this fixes a memory leak, as after commit c36f0555
("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()")
we call genl_family_rcv_msg_attrs_parse() for both parallel and
non-parallel cases.

Fixes: c36f0555 ("genetlink: fix memory leaks in genl_family_rcv_msg_dumpit()")
Reported-by: default avatarIdo Schimmel <idosch@idosch.org>
Signed-off-by: default avatarCong Wang <xiyou.wangcong@gmail.com>
Reviewed-by: default avatarIdo Schimmel <idosch@mellanox.com>
Tested-by: default avatarIdo Schimmel <idosch@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 18dbd4cd

net/netlink/genetlink.c

+12 −16
Original line number Original line Diff line number Diff line
@@ -474,8 +474,7 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, 
				struct netlink_ext_ack *extack,

				struct netlink_ext_ack *extack,

				const struct genl_ops *ops,

				const struct genl_ops *ops,

				int hdrlen,

				int hdrlen,

				enum genl_validate_flags no_strict_flag,

				enum genl_validate_flags no_strict_flag)

				bool parallel)

{

{

	enum netlink_validation validate = ops->validate & no_strict_flag ?

	enum netlink_validation validate = ops->validate & no_strict_flag ?

					   NL_VALIDATE_LIBERAL :

					   NL_VALIDATE_LIBERAL :
@@ -486,7 +485,7 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, 
	if (!family->maxattr)

	if (!family->maxattr)

		return NULL;

		return NULL;





	if (parallel) {

	if (family->parallel_ops) {

		attrbuf = kmalloc_array(family->maxattr + 1,

		attrbuf = kmalloc_array(family->maxattr + 1,

					sizeof(struct nlattr *), GFP_KERNEL);

					sizeof(struct nlattr *), GFP_KERNEL);

		if (!attrbuf)

		if (!attrbuf)
@@ -498,7 +497,7 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, 
	err = __nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr,

	err = __nlmsg_parse(nlh, hdrlen, attrbuf, family->maxattr,

			    family->policy, validate, extack);

			    family->policy, validate, extack);

	if (err) {

	if (err) {

		if (parallel)

		if (family->parallel_ops)

			kfree(attrbuf);

			kfree(attrbuf);

		return ERR_PTR(err);

		return ERR_PTR(err);

	}

	}
@@ -506,10 +505,9 @@ genl_family_rcv_msg_attrs_parse(const struct genl_family *family, 
}

}





static void genl_family_rcv_msg_attrs_free(const struct genl_family *family,

static void genl_family_rcv_msg_attrs_free(const struct genl_family *family,

					   struct nlattr **attrbuf,

					   struct nlattr **attrbuf)

					   bool parallel)

{

{

	if (parallel)

	if (family->parallel_ops)

		kfree(attrbuf);

		kfree(attrbuf);

}

}
@@ -537,15 +535,14 @@ static int genl_start(struct netlink_callback *cb) 




	attrs = genl_family_rcv_msg_attrs_parse(ctx->family, ctx->nlh, ctx->extack,

	attrs = genl_family_rcv_msg_attrs_parse(ctx->family, ctx->nlh, ctx->extack,

						ops, ctx->hdrlen,

						ops, ctx->hdrlen,

						GENL_DONT_VALIDATE_DUMP_STRICT,

						GENL_DONT_VALIDATE_DUMP_STRICT);

						true);

	if (IS_ERR(attrs))

	if (IS_ERR(attrs))

		return PTR_ERR(attrs);

		return PTR_ERR(attrs);





no_attrs:

no_attrs:

	info = genl_dumpit_info_alloc();

	info = genl_dumpit_info_alloc();

	if (!info) {

	if (!info) {

		kfree(attrs);

		genl_family_rcv_msg_attrs_free(ctx->family, attrs);

		return -ENOMEM;

		return -ENOMEM;

	}

	}

	info->family = ctx->family;

	info->family = ctx->family;
@@ -562,7 +559,7 @@ no_attrs: 
	}

	}





	if (rc) {

	if (rc) {

		kfree(attrs);

		genl_family_rcv_msg_attrs_free(info->family, info->attrs);

		genl_dumpit_info_free(info);

		genl_dumpit_info_free(info);

		cb->data = NULL;

		cb->data = NULL;

	}

	}
@@ -591,7 +588,7 @@ static int genl_lock_done(struct netlink_callback *cb) 
		rc = ops->done(cb);

		rc = ops->done(cb);

		genl_unlock();

		genl_unlock();

	}

	}

	genl_family_rcv_msg_attrs_free(info->family, info->attrs, false);

	genl_family_rcv_msg_attrs_free(info->family, info->attrs);

	genl_dumpit_info_free(info);

	genl_dumpit_info_free(info);

	return rc;

	return rc;

}

}
@@ -604,7 +601,7 @@ static int genl_parallel_done(struct netlink_callback *cb) 




	if (ops->done)

	if (ops->done)

		rc = ops->done(cb);

		rc = ops->done(cb);

	genl_family_rcv_msg_attrs_free(info->family, info->attrs, true);

	genl_family_rcv_msg_attrs_free(info->family, info->attrs);

	genl_dumpit_info_free(info);

	genl_dumpit_info_free(info);

	return rc;

	return rc;

}

}
@@ -671,8 +668,7 @@ static int genl_family_rcv_msg_doit(const struct genl_family *family, 




	attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,

	attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,

						  ops, hdrlen,

						  ops, hdrlen,

						  GENL_DONT_VALIDATE_STRICT,

						  GENL_DONT_VALIDATE_STRICT);

						  family->parallel_ops);

	if (IS_ERR(attrbuf))

	if (IS_ERR(attrbuf))

		return PTR_ERR(attrbuf);

		return PTR_ERR(attrbuf);
@@ -698,7 +694,7 @@ static int genl_family_rcv_msg_doit(const struct genl_family *family, 
		family->post_doit(ops, skb, &info);

		family->post_doit(ops, skb, &info);





out:

out:

	genl_family_rcv_msg_attrs_free(family, attrbuf, family->parallel_ops);

	genl_family_rcv_msg_attrs_free(family, attrbuf);





	return err;

	return err;

}

}

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