device: store the original MTU before force-setting it

In case the MTU is force-set (e.g. for bridges), priv->mtu_initial and
priv->ip6_mtu_initial must be initialized before changing the MTU,
otherwise the wrong value will be restored on deactivation.

Fixes: e23798a5e5 ('bridge: force (hack)-set of the MTU when explicitly set in the profile')

https://bugzilla.redhat.com/show_bug.cgi?id=1973536
https://gitlab.freedesktop.org/NetworkManager/NetworkManager/-/merge_requests/955
This commit is contained in:
Beniamino Galvani 2021-08-06 09:01:37 +02:00
parent a9279d1e89
commit 3f42e2005a

View file

@ -10689,10 +10689,30 @@ _commit_mtu(NMDevice *self, const NMIP4Config *config)
}
}
#define _IP6_MTU_SYS() \
({ \
if (!ip6_mtu_sysctl.initialized) { \
ip6_mtu_sysctl.value = nm_device_sysctl_ip_conf_get_int_checked(self, \
AF_INET6, \
"mtu", \
10, \
0, \
G_MAXUINT32, \
0); \
ip6_mtu_sysctl.initialized = TRUE; \
} \
ip6_mtu_sysctl.value; \
})
if (mtu_desired && NM_DEVICE_GET_CLASS(self)->mtu_force_set && !priv->mtu_force_set_done) {
priv->mtu_force_set_done = TRUE;
if (mtu_desired == mtu_plat) {
if (!priv->mtu_initial && !priv->ip6_mtu_initial) {
/* before touching any of the MTU parameters, record the
* original setting to restore on deactivation. */
priv->mtu_initial = mtu_plat;
priv->ip6_mtu_initial = _IP6_MTU_SYS();
}
mtu_plat--;
if (NM_DEVICE_GET_CLASS(self)->set_platform_mtu(self, mtu_desired - 1)) {
_LOGD(LOGD_DEVICE, "mtu: force-set MTU to %u", mtu_desired - 1);
@ -10711,20 +10731,6 @@ _commit_mtu(NMDevice *self, const NMIP4Config *config)
ip6_mtu == ip6_mtu_orig ? "" : nm_sprintf_buf(sbuf2, " (was %u)", (guint) ip6_mtu_orig),
ifindex);
#define _IP6_MTU_SYS() \
({ \
if (!ip6_mtu_sysctl.initialized) { \
ip6_mtu_sysctl.value = nm_device_sysctl_ip_conf_get_int_checked(self, \
AF_INET6, \
"mtu", \
10, \
0, \
G_MAXUINT32, \
0); \
ip6_mtu_sysctl.initialized = TRUE; \
} \
ip6_mtu_sysctl.value; \
})
if ((mtu_desired && mtu_desired != mtu_plat) || (ip6_mtu && ip6_mtu != _IP6_MTU_SYS())) {
gboolean anticipated_failure = FALSE;