Commit c10e6cf8 authored by Jiri Pirko's avatar Jiri Pirko Committed by David S. Miller
Browse files

net: genetlink: push attrbuf allocation and parsing to a separate function 



To be re-usable by dumpit as well, push the code that is taking care of
attrbuf allocation and parting from doit into separate function.
Introduce a helper to free the buffer too.

Check family->maxattr too before calling kfree() to be symmetrical with
the allocation check.

Signed-off-by: default avatarJiri Pirko <jiri@mellanox.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 1927f41a

net/netlink/genetlink.c

+45 −22
Original line number Diff line number Diff line
@@ -468,6 +468,45 @@ static void genl_dumpit_info_free(const struct genl_dumpit_info *info) 
	kfree(info);

}



static struct nlattr **

genl_family_rcv_msg_attrs_parse(const struct genl_family *family,

				struct nlmsghdr *nlh,

				struct netlink_ext_ack *extack,

				const struct genl_ops *ops,

				int hdrlen,

				enum genl_validate_flags no_strict_flag)

{

	enum netlink_validation validate = ops->validate & no_strict_flag ?

					   NL_VALIDATE_LIBERAL :

					   NL_VALIDATE_STRICT;

	struct nlattr **attrbuf;

	int err;



	if (family->maxattr && family->parallel_ops) {

		attrbuf = kmalloc_array(family->maxattr + 1,

					sizeof(struct nlattr *), GFP_KERNEL);

		if (!attrbuf)

			return ERR_PTR(-ENOMEM);

	} else {

		attrbuf = family->attrbuf;

	}



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

			    family->policy, validate, extack);

	if (err && family->maxattr && family->parallel_ops) {

		kfree(attrbuf);

		return ERR_PTR(err);

	}

	return attrbuf;

}



static void genl_family_rcv_msg_attrs_free(const struct genl_family *family,

					   struct nlattr **attrbuf)

{

	if (family->maxattr && family->parallel_ops)

		kfree(attrbuf);

}



static int genl_lock_start(struct netlink_callback *cb)

{

	const struct genl_ops *ops = genl_dumpit_info(cb)->ops;
@@ -599,26 +638,11 @@ static int genl_family_rcv_msg_doit(const struct genl_family *family, 
	if (!ops->doit)

		return -EOPNOTSUPP;



	if (family->maxattr && family->parallel_ops) {

		attrbuf = kmalloc_array(family->maxattr + 1,

					sizeof(struct nlattr *),

					GFP_KERNEL);

		if (attrbuf == NULL)

			return -ENOMEM;

	} else

		attrbuf = family->attrbuf;



	if (attrbuf) {

		enum netlink_validation validate = NL_VALIDATE_STRICT;



		if (ops->validate & GENL_DONT_VALIDATE_STRICT)

			validate = NL_VALIDATE_LIBERAL;



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

				    family->policy, validate, extack);

		if (err < 0)

			goto out;

	}

	attrbuf = genl_family_rcv_msg_attrs_parse(family, nlh, extack,

						  ops, hdrlen,

						  GENL_DONT_VALIDATE_STRICT);

	if (IS_ERR(attrbuf))

		return PTR_ERR(attrbuf);



	info.snd_seq = nlh->nlmsg_seq;

	info.snd_portid = NETLINK_CB(skb).portid;
@@ -642,8 +666,7 @@ static int genl_family_rcv_msg_doit(const struct genl_family *family, 
		family->post_doit(ops, skb, &info);



out:

	if (family->parallel_ops)

		kfree(attrbuf);

	genl_family_rcv_msg_attrs_free(family, attrbuf);



	return err;

}

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