[libvirt] [PATCH 3/4] util: use nlmsg_find_attr() instead of an open-coded loop

This is about the same number of code lines, but is simpler, and more consistent with what will be added to check another attribute in a coming patch. As a side effect, it Resolves: https://bugzilla.redhat.com/1583131 Signed-off-by: Laine Stump <laine(a)laine.org&gt; --- src/util/virnetdevip.c | 53 ++++++++++++++++++------------------------ 1 file changed, 23 insertions(+), 30 deletions(-) diff --git a/src/util/virnetdevip.c b/src/util/virnetdevip.c index 72048e4b45..c032ecacfc 100644 --- a/src/util/virnetdevip.c +++ b/src/util/virnetdevip.c @@ -529,49 +529,42 @@ virNetDevIPCheckIPv6ForwardingCallback(struct nlmsghdr *resp, void *opaque) { struct rtmsg *rtmsg = NLMSG_DATA(resp); - int accept_ra = -1; - struct rtattr *rta; struct virNetDevIPCheckIPv6ForwardingData *data = opaque; - int len = RTM_PAYLOAD(resp); - int oif = -1; + struct rtattr *rta_attr; + int accept_ra = -1; + int ifindex = -1; VIR_AUTOFREE(char *) ifname = NULL; /* Ignore messages other than route ones */ if (resp->nlmsg_type != RTM_NEWROUTE) return 0; - /* Extract a device ID attribute */ - VIR_WARNINGS_NO_CAST_ALIGN - for (rta = RTM_RTA(rtmsg); RTA_OK(rta, len); rta = RTA_NEXT(rta, len)) { - VIR_WARNINGS_RESET - if (rta->rta_type == RTA_OIF) { - oif = *(int *)RTA_DATA(rta); - - /* Should never happen: netlink message would be broken */ - if (ifname) { - VIR_AUTOFREE(char *) ifname2 = virNetDevGetName(oif); - VIR_WARN("Single route has unexpected 2nd interface " - "- '%s' and '%s'", ifname, ifname2); - break; - } - - if (!(ifname = virNetDevGetName(oif))) - return -1; - } - } - /* No need to do anything else for non RA routes */ if (rtmsg->rtm_protocol != RTPROT_RA) return 0; - data->hasRARoutes = true; + rta_attr = (struct rtattr *)nlmsg_find_attr(resp, sizeof(struct rtmsg), RTA_OIF); + if (rta_attr) { + /* This is a single path route, with interface used to reach + * nexthop in the RTA_OIF attribute. + */ + ifindex = *(int *)RTA_DATA(rta_attr); + ifname = virNetDevGetName(ifindex); - /* Check the accept_ra value for the interface */ - accept_ra = virNetDevIPGetAcceptRA(ifname); - VIR_DEBUG("Checking route for device %s, accept_ra: %d", ifname, accept_ra); + if (ifname) + accept_ra = virNetDevIPGetAcceptRA(ifname); - if (accept_ra != 2 && virNetDevIPCheckIPv6ForwardingAddIF(data, &ifname) < 0) - return -1; + VIR_DEBUG("Checking route for device %s (%d), accept_ra: %d", + ifname, ifindex, accept_ra); + + if (!ifname || + (accept_ra != 2 && virNetDevIPCheckIPv6ForwardingAddIF(data, &ifname) < 0)) { + return -1; + } + + data->hasRARoutes = true; + return 0; + } return 0; } -- 2.20.1