The current Linux implementation checks whether a node supports
IPv6 by testing for the presence of '/proc/net/if_inet6'. However,
that check does not confirm that IPv6 support is actually enabled.
As a result, kube-proxy can incorrectly enable dual‑stack support
on nodes that do not have IPv6 enabled.
The possibility to disable IPv6 support has existed since
Linux kernel v2.6.27.
Update the IPv6 support check to also consider the contents of
'/proc/sys/net/ipv6/conf/all/disable_ipv6'.
Signed-off-by: Tero Kauppinen <tero.kauppinen@est.tech>
FSWatcher.Run() spawned a goroutine with no exit mechanism, causing a
goroutine leak. Add a ctx context.Context parameter to Run() so the
goroutine can exit cleanly when the context is canceled, and
defer-close the underlying fsnotify watcher on exit.
For kube-proxy, the existing ctx from runLoop() is passed directly.
For the flexvolume prober, ctx is stored in flexVolumeProber at
construction time via GetDynamicPluginProber(), representing the
component lifetime (kubelet/controller-manager), which is the
appropriate scope for this long-running watcher.
This has been replaced by `//build:...` for a long time now.
Removal of the old build tag was automated with:
for i in $(git grep -l '^// +build' | grep -v -e '^vendor/'); do if ! grep -q '^// Code generated' "$i"; then sed -i -e '/^\/\/ +build/d' "$i"; fi; done
The semantics (sometimes it returns an error that is really just a
warning) are too confusing, and it turns out that we really only need
it in one place (platformCheckSupported()); after that we've already
figured out what IP families are supported, so we could just use
utiliptables.NewBestEffort() instead, knowing we want exactly what it
returns.
So we can just expand the semantics of the old NewDualStack() inline
in the one place we care, without hiding any of it behind a
too-complicated return value.
ProxyHealthServer now consumes NodeManager to get the latest
updated node object for determining node eligibility.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
Co-authored-by: Dan Winship <danwinship@redhat.com>
NodeManager, if configured with to watch for PodCIDR watch, watches
for changes in PodCIDRs and crashes kube-proxy if a change is
detected in PodCIDRs.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
Co-authored-by: Dan Winship <danwinship@redhat.com>
NodeManager initialises node informers, waits for cache sync and polls for
node object to retrieve NodeIPs, handle node events and crashes kube-proxy
when change in NodeIPs is detected.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
Co-authored-by: Dan Winship <danwinship@redhat.com>
This simplifies how the proxier receives update for change in node
labels. Instead of passing the complete Node object we just pass
the proxy relevant topology labels extracted from the complete list
of labels, and the downstream event handlers will only be notified
when there are changes in topology labels.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
ProxyHealthServer now consumes NodeManager to get the latest
updated node object for determining node eligibility.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
NodeManager, if configured with to watch for PodCIDR watch, watches
for changes in PodCIDRs and crashes kube-proxy if a change is
detected in PodCIDRs.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
NodeManager initialises node informers, waits for cache sync and polls for
node object to retrieve NodeIPs, handle node events and crashes kube-proxy
when change in NodeIPs is detected.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
This simplifies how the proxier receives update for change in node
labels. Instead of passing the complete Node object we just pass
the proxy relevant topology labels extracted from the complete list
of labels, and the downstream event handlers will only be notified
when there are changes in topology labels.
Signed-off-by: Daman Arora <aroradaman@gmail.com>
IPv6 should also be checked if it is globally enabled. On nftables, today this
is hardcoded, so if a Linux Kernel disables IPv6 during its boot or doesn't
have IPv6 compiled, it will still try to use IPv6, which can lead to some
unexpected errors.
This change verifies if IPv6 is enabled by checking if the IPv6 network interfaces
proc file is available
This also fixes it so that ipvs.CleanupLeftovers only deletes
ipvs/ipset stuff once, rather than first deleting all of it on behalf
of the IPv4 Proxier and then no-op "deleting" it all again on behalf
of the IPv6 Proxier.
Various parts of kube-proxy passed around a "hostname", but it is
actually the name of the *node* kube-proxy is running on, which is not
100% guaranteed to be exactly the same as the hostname. Rename it
everywhere to make it clearer that (a) it is definitely safe to use
that name to refer to the Node, (b) it is not necessarily safe to use
that name with DNS, etc.
Basically all callers want dual-stack-if-possible, so simplify that.
Also, tweak the startup-time checking in kubelet to treat "no iptables
support" as interesting but not an error.
It was there so you could mock the results via a FakeExec, but these
days any unit tests outside of pkg/util/iptables that want to mock
iptables results use a FakeIPTables instead of a real
utiliptables.Interface with a FakeExec.
Historically it took an exec argument so you could pass a FakeExec to
mock its behavior in unit tests, but it has a fake implementation now
that is much more useful for unit tests than trying to use the real
implementation with a fake exec. (The unit tests still use fake execs,
but they don't need to use a public constructor.) So remove the exec
args from the public constructors.
Remove the utilexec.Interface args from the iptables/ipvs constructors
(which have been unused since the conntrack cleanup code was ported to
netlink).
Remove the EventRecorder fields from the iptables/ipvs Proxiers, which
have been unused since we removed the port-opener code in 2022.
Remove the strictARP field from the ipvs Proxier, which has apparently
always been unused (strictARP is only looked at at construct time).
