Commit f5046fbc authored by Kuniyuki Iwashima's avatar Kuniyuki Iwashima Committed by Jakub Kicinski
Browse files

neighbour: Move two validations from neigh_get() to neigh_valid_get_req(). 



We will remove RTNL for neigh_get() and run it under RCU instead.

neigh_get() returns -EINVAL in the following cases:

  * NDA_DST is not specified
  * Both ndm->ndm_ifindex and NTF_PROXY are not specified

These validations do not require RCU.

Let's move them to neigh_valid_get_req().

While at it, the extack string for the first case is replaced with
NL_SET_ERR_ATTR_MISS().

Signed-off-by: default avatarKuniyuki Iwashima <kuniyu@google.com>
Link: https://patch.msgid.link/20250716221221.442239-3-kuniyu@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent caf0a753

net/core/neighbour.c

+13 −13
Original line number Diff line number Diff line
@@ -2935,6 +2935,11 @@ static struct ndmsg *neigh_valid_get_req(const struct nlmsghdr *nlh, 
		return ERR_PTR(-EINVAL);

	}



	if (!(ndm->ndm_flags & NTF_PROXY) && !ndm->ndm_ifindex) {

		NL_SET_ERR_MSG(extack, "No device specified");

		return ERR_PTR(-EINVAL);

	}



	err = nlmsg_parse_deprecated_strict(nlh, sizeof(struct ndmsg), tb,

					    NDA_MAX, nda_policy, extack);

	if (err < 0)
@@ -2947,11 +2952,13 @@ static struct ndmsg *neigh_valid_get_req(const struct nlmsghdr *nlh, 
	}



	for (i = 0; i <= NDA_MAX; ++i) {

		if (!tb[i])

			continue;



		switch (i) {

		case NDA_DST:

			if (!tb[i]) {

				NL_SET_ERR_ATTR_MISS(extack, NULL, NDA_DST);

				return ERR_PTR(-EINVAL);

			}



			if (nla_len(tb[i]) != (int)(*tbl)->key_len) {

				NL_SET_ERR_MSG(extack, "Invalid network address in neighbor get request");

				return ERR_PTR(-EINVAL);
@@ -2959,6 +2966,9 @@ static struct ndmsg *neigh_valid_get_req(const struct nlmsghdr *nlh, 
			*dst = nla_data(tb[i]);

			break;

		default:

			if (!tb[i])

				continue;



			NL_SET_ERR_MSG(extack, "Unsupported attribute in neighbor get request");

			return ERR_PTR(-EINVAL);

		}
@@ -3051,11 +3061,6 @@ static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh, 
		}

	}



	if (!dst) {

		NL_SET_ERR_MSG(extack, "Network address not specified");

		return -EINVAL;

	}



	if (ndm->ndm_flags & NTF_PROXY) {

		struct pneigh_entry *pn;
@@ -3068,11 +3073,6 @@ static int neigh_get(struct sk_buff *in_skb, struct nlmsghdr *nlh, 
					nlh->nlmsg_seq, tbl);

	}



	if (!dev) {

		NL_SET_ERR_MSG(extack, "No device specified");

		return -EINVAL;

	}



	neigh = neigh_lookup(tbl, dst, dev);

	if (!neigh) {

		NL_SET_ERR_MSG(extack, "Neighbour entry not found");