diff options
author | Lubomir Rintel <lkundrak@v3.sk> | 2015-02-25 15:35:26 +0100 |
---|---|---|
committer | Lubomir Rintel <lkundrak@v3.sk> | 2015-03-09 18:21:01 +0100 |
commit | 7ba2a058f201ac237e2c5ddf6f513f8c306f314d (patch) | |
tree | 2c1356a7e6a88c400034f76d1716819cc17d01e8 /src/devices | |
parent | 1bc202af028ad8987a92500bba6bb36156d8be5f (diff) | |
download | NetworkManager-7ba2a058f201ac237e2c5ddf6f513f8c306f314d.tar.gz |
nm-device: avoid improper IPv6 MTU configurationlr/ipv6-mtu-rh1194007
Ensure it's always (before address configuration starts and on updates) >= 1280
and not higher than the device MTU.
Diffstat (limited to 'src/devices')
-rw-r--r-- | src/devices/nm-device.c | 53 |
1 files changed, 49 insertions, 4 deletions
diff --git a/src/devices/nm-device.c b/src/devices/nm-device.c index 808ba6f0b1..c31b47667b 100644 --- a/src/devices/nm-device.c +++ b/src/devices/nm-device.c @@ -464,6 +464,12 @@ nm_device_ipv6_sysctl_set (NMDevice *self, const char *property, const char *val return nm_platform_sysctl_set (nm_utils_ip6_property_path (nm_device_get_ip_iface (self), property), value); } +static guint32 +nm_device_ipv6_sysctl_get_int32 (NMDevice *self, const char *property, gint32 fallback) +{ + return nm_platform_sysctl_get_int32 (nm_utils_ip6_property_path (nm_device_get_ip_iface (self), property), fallback); +} + static gboolean device_has_capability (NMDevice *self, NMDeviceCapabilities caps) { @@ -4079,21 +4085,53 @@ print_support_extended_ifa_flags (NMSettingIP6ConfigPrivacy use_tempaddr) warn = 2; } +static void nm_device_ipv6_set_mtu (NMDevice *self, guint32 mtu); + static void nm_device_set_mtu (NMDevice *self, guint32 mtu) { - /* MTU */ - if (mtu && mtu != nm_platform_link_get_mtu (ifindex)) - nm_platform_link_set_mtu (ifindex, mtu); + NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE (self); + int ifindex = nm_device_get_ifindex (self); + + if (mtu) + priv->mtu = mtu; + + /* Ensure the IPv6 MTU is still alright. */ + if (priv->ip6_mtu) + nm_device_ipv6_set_mtu (self, priv->ip6_mtu); + + if (priv->mtu != nm_platform_link_get_mtu (ifindex)) + nm_platform_link_set_mtu (ifindex, priv->mtu); } static void nm_device_ipv6_set_mtu (NMDevice *self, guint32 mtu) { NMDevicePrivate *priv = NM_DEVICE_GET_PRIVATE (self); + guint32 plat_mtu = nm_device_ipv6_sysctl_get_int32 (self, "mtu", priv->mtu); char val[16]; - if (mtu) { + priv->ip6_mtu = mtu ?: plat_mtu; + + if (priv->ip6_mtu && priv->mtu < priv->ip6_mtu) { + _LOGW (LOGD_DEVICE | LOGD_IP6, "Lowering IPv6 MTU (%d) to match device MTU (%d)", + priv->ip6_mtu, priv->mtu); + priv->ip6_mtu = priv->mtu; + } + + if (priv->ip6_mtu < 1280) { + _LOGW (LOGD_DEVICE | LOGD_IP6, "IPv6 MTU (%d) smaller than 1280, adjusting", + priv->ip6_mtu); + priv->ip6_mtu = 1280; + } + + if (priv->mtu < priv->ip6_mtu) { + _LOGW (LOGD_DEVICE | LOGD_IP6, "Raising device MTU (%d) to match IPv6 MTU (%d)", + priv->mtu, priv->ip6_mtu); + nm_device_set_mtu (self, priv->ip6_mtu); + } + + if (priv->ip6_mtu != plat_mtu) { g_snprintf (val, sizeof (val), "%d", mtu); nm_device_ipv6_sysctl_set (self, "mtu", val); } @@ -4598,6 +4636,13 @@ act_stage3_ip6_config_start (NMDevice *self, return NM_ACT_STAGE_RETURN_STOP; } + /* Ensure the MTU makes sense. If it was below 1280 the kernel would not + * expose any ipv6 sysctls or allow presence of any addresses on the interface, + * including LL, which * would make it impossible to autoconfigure MTU to a + * correct value. */ + if (!nm_device_uses_assumed_connection (self)) + nm_device_ipv6_set_mtu (self, priv->ip6_mtu); + /* Any method past this point requires an IPv6LL address. Use NM-controlled * IPv6LL if this is not an assumed connection, since assumed connections * will already have IPv6 set up. |