From a1f10abe12b6d70f8b02dedccb48c9d234a57b67 Mon Sep 17 00:00:00 2001 From: David Ahern Date: Sat, 27 May 2017 16:19:29 -0600 Subject: net: Fill in extack for mpls lwt encap Fill in extack for errors in build_state for mpls lwt encap including passing extack to nla_get_labels and adding error messages for failures in it. Signed-off-by: David Ahern Signed-off-by: David S. Miller --- net/mpls/af_mpls.c | 49 +++++++++++++++++++++++++++++++++++++++---------- 1 file changed, 39 insertions(+), 10 deletions(-) (limited to 'net/mpls/af_mpls.c') diff --git a/net/mpls/af_mpls.c b/net/mpls/af_mpls.c index 257ec66009da..f3830951fb1c 100644 --- a/net/mpls/af_mpls.c +++ b/net/mpls/af_mpls.c @@ -728,8 +728,8 @@ static int mpls_nh_build(struct net *net, struct mpls_route *rt, goto errout; if (newdst) { - err = nla_get_labels(newdst, max_labels, - &nh->nh_labels, nh->nh_label); + err = nla_get_labels(newdst, max_labels, &nh->nh_labels, + nh->nh_label, NULL); if (err) goto errout; } @@ -782,7 +782,8 @@ static u8 mpls_count_nexthops(struct rtnexthop *rtnh, int len, nla = nla_find(attrs, attrlen, RTA_NEWDST); if (nla && - nla_get_labels(nla, MAX_NEW_LABELS, &n_labels, NULL) != 0) + nla_get_labels(nla, MAX_NEW_LABELS, &n_labels, + NULL, NULL) != 0) return 0; *max_labels = max_t(u8, *max_labels, n_labels); @@ -1541,8 +1542,8 @@ int nla_put_labels(struct sk_buff *skb, int attrtype, } EXPORT_SYMBOL_GPL(nla_put_labels); -int nla_get_labels(const struct nlattr *nla, - u8 max_labels, u8 *labels, u32 label[]) +int nla_get_labels(const struct nlattr *nla, u8 max_labels, u8 *labels, + u32 label[], struct netlink_ext_ack *extack) { unsigned len = nla_len(nla); struct mpls_shim_hdr *nla_label; @@ -1553,13 +1554,18 @@ int nla_get_labels(const struct nlattr *nla, /* len needs to be an even multiple of 4 (the label size). Number * of labels is a u8 so check for overflow. */ - if (len & 3 || len / 4 > 255) + if (len & 3 || len / 4 > 255) { + NL_SET_ERR_MSG_ATTR(extack, nla, + "Invalid length for labels attribute"); return -EINVAL; + } /* Limit the number of new labels allowed */ nla_labels = len/4; - if (nla_labels > max_labels) + if (nla_labels > max_labels) { + NL_SET_ERR_MSG(extack, "Too many labels"); return -EINVAL; + } /* when label == NULL, caller wants number of labels */ if (!label) @@ -1574,8 +1580,29 @@ int nla_get_labels(const struct nlattr *nla, /* Ensure the bottom of stack flag is properly set * and ttl and tc are both clear. */ - if ((dec.bos != bos) || dec.ttl || dec.tc) + if (dec.ttl) { + NL_SET_ERR_MSG_ATTR(extack, nla, + "TTL in label must be 0"); + return -EINVAL; + } + + if (dec.tc) { + NL_SET_ERR_MSG_ATTR(extack, nla, + "Traffic class in label must be 0"); return -EINVAL; + } + + if (dec.bos != bos) { + NL_SET_BAD_ATTR(extack, nla); + if (bos) { + NL_SET_ERR_MSG(extack, + "BOS bit must be set in first label"); + } else { + NL_SET_ERR_MSG(extack, + "BOS bit can only be set in first label"); + } + return -EINVAL; + } switch (dec.label) { case MPLS_LABEL_IMPLNULL: @@ -1583,6 +1610,8 @@ int nla_get_labels(const struct nlattr *nla, * assign and distribute, but which never * actually appears in the encapsulation. */ + NL_SET_ERR_MSG_ATTR(extack, nla, + "Implicit NULL Label (3) can not be used in encapsulation"); return -EINVAL; } @@ -1696,14 +1725,14 @@ static int rtm_to_route_config(struct sk_buff *skb, struct nlmsghdr *nlh, case RTA_NEWDST: if (nla_get_labels(nla, MAX_NEW_LABELS, &cfg->rc_output_labels, - cfg->rc_output_label)) + cfg->rc_output_label, NULL)) goto errout; break; case RTA_DST: { u8 label_count; if (nla_get_labels(nla, 1, &label_count, - &cfg->rc_label)) + &cfg->rc_label, NULL)) goto errout; /* Reserved labels may not be set */ -- cgit