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ctlplane: handle interface renaming #450

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Merged
christophefontaine merged 1 commit into from
Dec 10, 2025
Merged

ctlplane: handle interface renaming #450

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8 changes: 8 additions & 0 deletions modules/infra/control/ctlplane.c
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Original file line number Diff line number Diff line change
Expand Up @@ -383,10 +383,18 @@ static void cp_set_speed(struct iface *iface) {
}

static void cp_update(struct iface *iface) {
char current_name[IFNAMSIZ];
struct rte_ether_addr mac;
struct ifreq ifr = {0};
int ioctl_sock;

if (iface->cp_id > 0) {
if (if_indextoname(iface->cp_id, current_name) != NULL
&& strcmp(current_name, iface->name) != 0) {
netlink_link_set_name(iface->cp_id, iface->name);
}
Comment on lines +391 to +395
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@coderabbitai coderabbitai bot Dec 10, 2025

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⚠️ Potential issue | 🟠 Major

Handle rename failure.

The return value from netlink_link_set_name is not checked. If the rename fails, the code continues silently, potentially causing a mismatch between iface->name and the actual kernel interface name. This could lead to subsequent ioctl operations failing or operating on the wrong interface.

Apply this diff to add error handling:

 	if (iface->cp_id > 0) {
 		if (if_indextoname(iface->cp_id, current_name) != NULL
 		    && strcmp(current_name, iface->name) != 0) {
-			netlink_link_set_name(iface->cp_id, iface->name);
+			if (netlink_link_set_name(iface->cp_id, iface->name) < 0) {
+				LOG(ERR, "netlink_link_set_name(%u, %s): %s",
+				    iface->cp_id, iface->name, strerror(errno));
+			}
 		}
 	}
🤖 Prompt for AI Agents 
In modules/infra/control/ctlplane.c around lines 391-395, the call to
netlink_link_set_name lacks error handling; check its return value and if it
indicates failure, log the error (include errno/strerror(errno) or the
function's error string) and prevent further operations on the wrong interface —
for example, clear iface->cp_id or return an error from the enclosing function
so subsequent ioctl calls are not made against a mismatched kernel name. Ensure
the log message includes iface->cp_id and iface->name for context.

}

if ((ioctl_sock = socket(AF_INET, SOCK_DGRAM, 0)) < 0) {
LOG(ERR, "socket(SOCK_DGRAM): %s", strerror(errno));
goto err;
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1 change: 1 addition & 0 deletions modules/infra/control/gr_netlink.h
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Original file line number Diff line number Diff line change
Expand Up @@ -9,6 +9,7 @@

int netlink_link_set_admin_state(const char *ifname, bool up);
int netlink_link_set_master(const char *ifname, const char *master_ifname);
int netlink_link_set_name(uint32_t ifindex, const char *ifname);
int netlink_link_add_vrf(const char *vrf_name, uint32_t table_id);
int netlink_link_del_iface(const char *ifname);
int netlink_add_route(const char *ifname, uint32_t table);
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19 changes: 19 additions & 0 deletions modules/infra/control/netlink.c
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Original file line number Diff line number Diff line change
Expand Up @@ -328,6 +328,25 @@ int netlink_set_ifalias(const char *ifname, const char *ifalias) {
return netlink_send_req(nlh);
}

int netlink_link_set_name(uint32_t ifindex, const char *ifname) {
char buf[NLMSG_SPACE(sizeof(struct ifinfomsg) + NLA_SPACE(IFNAMSIZ))];
struct ifinfomsg *ifm;
struct nlmsghdr *nlh;

memset(buf, 0, sizeof(buf));
nlh = mnl_nlmsg_put_header(buf);
nlh->nlmsg_type = RTM_SETLINK;
nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;

ifm = mnl_nlmsg_put_extra_header(nlh, sizeof(*ifm));
ifm->ifi_family = AF_UNSPEC;
ifm->ifi_index = ifindex;

mnl_attr_put_strz(nlh, IFLA_IFNAME, ifname);

return netlink_send_req(nlh);
}

static void netlink_init(struct event_base *) {
nl_sock = mnl_socket_open(NETLINK_ROUTE);
if (!nl_sock)
Expand Down