[libvirt] [PATCH] network: always set disable_ipv6, even when it should be 0
libvirt previously only touched an interface's disable_ipv6 setting in
sysfs if it needed to be set to 1, assuming that 0 is the
default. Apparently that isn't always the case though (kernel 3.15.7-1
in Arch Linux reportedly defaults a new interface's disable_ipv6
setting to 1) so this patch explicitly sets it to 0 or 1 as
appropriate.
---
src/network/bridge_driver.c | 41 +++++++++++++++++++++--------------------
1 file changed, 21 insertions(+), 20 deletions(-)
diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c
index 6ccc6e2..965fdec 100644
--- a/src/network/bridge_driver.c
+++ b/src/network/bridge_driver.c
@@ -1824,33 +1824,34 @@ networkSetIPv6Sysctls(virNetworkObjPtr network)
{
char *field = NULL;
int ret = -1;
+ bool enableIPv6 = !!virNetworkDefGetIpByIndex(network->def, AF_INET6, 0);
- if (!virNetworkDefGetIpByIndex(network->def, AF_INET6, 0)) {
- /* Only set disable_ipv6 if there are no ipv6 addresses defined for
- * the network.
- */
- if (virAsprintf(&field, SYSCTL_PATH
"/net/ipv6/conf/%s/disable_ipv6",
- network->def->bridge) < 0)
- goto cleanup;
+ /* set disable_ipv6 if there are no ipv6 addresses defined for the
+ * network. But also unset it if there *are* ipv6 addresses, as we
+ * can't be sure of its default value.
+ */
+ if (virAsprintf(&field, SYSCTL_PATH "/net/ipv6/conf/%s/disable_ipv6",
+ network->def->bridge) < 0)
+ goto cleanup;
- if (access(field, W_OK) < 0 && errno == ENOENT) {
+ if (access(field, W_OK) < 0 && errno == ENOENT) {
+ if (!enableIPv6)
VIR_DEBUG("ipv6 appears to already be disabled on %s",
network->def->bridge);
- ret = 0;
- goto cleanup;
- }
+ ret = 0;
+ goto cleanup;
+ }
- if (virFileWriteStr(field, "1", 0) < 0) {
- virReportSystemError(errno,
- _("cannot write to %s to disable IPv6 on bridge
%s"),
- field, network->def->bridge);
- goto cleanup;
- }
- VIR_FREE(field);
+ if (virFileWriteStr(field, enableIPv6 ? "0" : "1", 0) < 0) {
+ virReportSystemError(errno,
+ _("cannot write to %s to enable/disable IPv6 "
+ "on bridge %s"), field,
network->def->bridge);
+ goto cleanup;
}
+ VIR_FREE(field);
- /* The rest of the ipv6 sysctl tunables should always be set,
- * whether or not we're using ipv6 on this bridge.
+ /* The rest of the ipv6 sysctl tunables should always be set the
+ * same, whether or not we're using ipv6 on this bridge.
*/
/* Prevent guests from hijacking the host network by sending out
--
1.9.3