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f5418b427e
When firewalld is stopped, it removes *all* iptables rules and chains, including those added by libvirt. Since restarting firewalld means stopping and then starting it, any time it is restarted, libvirt needs to recreate all the private iptables chains it uses, along with all the rules it adds. We already have code in place to call networkReloadFirewallRules() any time we're notified of a firewalld start, and networkReloadFirewallRules() will call networkPreReloadFirewallRules(), which calls networkSetupPrivateChains(); unfortunately that last call is called using virOnce(), meaning that it will only be called the first time through networkPreReloadFirewallRules() after libvirtd starts - so of course when firewalld is later restarted, the call to networkSetupPrivateChains() is skipped. The neat and tidy way to fix this would be if there was a standard way to reset a pthread_once_t object so that the next time virOnce was called, it would think the function hadn't been called, and call it again. Unfortunately, there isn't any official way of doing that (we *could* just fill it with 0 and hope for the best, but that doesn't seem very safe. So instead, this patch just adds a static variable called chainInitDone, which is set to true after networkSetupPrivateChains() is called for the first time, and then during calls to networkPreReloadFirewallRules(), if chainInitDone is set, we call networkSetupPrivateChains() directly instead of via virOnce(). It may seem unsafe to directly call a function that is meant to be called only once, but I think in this case we're safe - there's nothing in the function that is inherently "once only" - it doesn't initialize anything that can't safely be re-initialized (as long as two threads don't try to do it at the same time), and it only happens when responding to a dbus message that firewalld has been started (and I don't think it's possible for us to be processing two of those at once), and even then only if the initial call to the function has already been completed (so we're safe if we receive a firewalld restart call at a time when we haven't yet called it, or even if another thread is already in the process of executing it. The only problematic bit I can think of is if another thread is in the process of adding an iptable rule at the time we're executing this function, but 1) none of those threads will be trying to add chains, and 2) if there was a concurrency problem with other threads adding iptables rules while firewalld was being restarted, it would still be a problem even without this change. This is yet another patch that fixes an occurrence of this error: COMMAND_FAILED: '/usr/sbin/iptables -w10 -w --table filter --insert LIBVIRT_INP --in-interface virbr0 --protocol tcp --destination-port 67 --jump ACCEPT' failed: iptables: No chain/target/match by that name. In particular, this resolves: https://bugzilla.redhat.com/1813830 Signed-off-by: Laine Stump <laine@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com> |
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|---|---|---|
| .. | ||
| access | ||
| admin | ||
| bhyve | ||
| conf | ||
| cpu | ||
| cpu_map | ||
| esx | ||
| hyperv | ||
| hypervisor | ||
| interface | ||
| keycodemapdb@27acf0ef82 | ||
| libxl | ||
| locking | ||
| logging | ||
| lxc | ||
| network | ||
| node_device | ||
| nwfilter | ||
| openvz | ||
| qemu | ||
| remote | ||
| rpc | ||
| secret | ||
| security | ||
| storage | ||
| test | ||
| util | ||
| vbox | ||
| vmware | ||
| vmx | ||
| vz | ||
| admin_protocol-structs | ||
| datatypes.c | ||
| datatypes.h | ||
| driver-hypervisor.h | ||
| driver-interface.h | ||
| driver-network.h | ||
| driver-nodedev.h | ||
| driver-nwfilter.h | ||
| driver-secret.h | ||
| driver-state.h | ||
| driver-storage.h | ||
| driver-stream.h | ||
| driver.c | ||
| driver.h | ||
| internal.h | ||
| libvirt_driver_modules.syms | ||
| libvirt_esx.syms | ||
| libvirt_internal.h | ||
| libvirt_libssh2.syms | ||
| libvirt_libssh.syms | ||
| libvirt_linux.syms | ||
| libvirt_lxc.syms | ||
| libvirt_openvz.syms | ||
| libvirt_private.syms | ||
| libvirt_probes.d | ||
| libvirt_public.syms | ||
| libvirt_qemu_probes.d | ||
| libvirt_qemu.syms | ||
| libvirt_remote.syms | ||
| libvirt_sasl.syms | ||
| libvirt_vmware.syms | ||
| libvirt_vmx.syms | ||
| libvirt-domain-checkpoint.c | ||
| libvirt-domain-snapshot.c | ||
| libvirt-domain.c | ||
| libvirt-host.c | ||
| libvirt-interface.c | ||
| libvirt-lxc.c | ||
| libvirt-lxc.pc.in | ||
| libvirt-network.c | ||
| libvirt-nodedev.c | ||
| libvirt-nwfilter.c | ||
| libvirt-qemu.c | ||
| libvirt-qemu.pc.in | ||
| libvirt-secret.c | ||
| libvirt-storage.c | ||
| libvirt-stream.c | ||
| libvirt.c | ||
| libvirt.conf | ||
| libvirt.pc.in | ||
| lock_protocol-structs | ||
| lxc_monitor_protocol-structs | ||
| lxc_protocol-structs | ||
| Makefile.am | ||
| qemu_protocol-structs | ||
| README | ||
| remote_protocol-structs | ||
| virkeepaliveprotocol-structs | ||
| virnetprotocol-structs | ||
libvirt library code README
===========================
The directory provides the bulk of the libvirt codebase. Everything
except for the libvirtd daemon and client tools. The build uses a
large number of libtool convenience libraries - one for each child
directory, and then links them together for the final libvirt.so,
although some bits get linked directly to libvirtd daemon instead.
The files directly in this directory are supporting the public API
entry points & data structures.
There are two core shared modules to be aware of:
* util/ - a collection of shared APIs that can be used by any
code. This directory is always in the include path
for all things built
* conf/ - APIs for parsing / manipulating all the official XML
files used by the public API. This directory is only
in the include path for driver implementation modules
* vmx/ - VMware VMX config handling (used by esx/ and vmware/)
Then there are the hypervisor implementations:
* bhyve - bhyve - The BSD Hypervisor
* esx/ - VMware ESX and GSX support using vSphere API over SOAP
* hyperv/ - Microsoft Hyper-V support using WinRM
* lxc/ - Linux Native Containers
* openvz/ - OpenVZ containers using cli tools
* qemu/ - QEMU / KVM using qemu CLI/monitor
* remote/ - Generic libvirt native RPC client
* test/ - A "mock" driver for testing
* vbox/ - Virtual Box using native API
* vmware/ - VMware Workstation and Player using the vmrun tool
* xen/ - Xen using hypercalls, XenD SEXPR & XenStore
Finally some secondary drivers that are shared for several HVs.
Currently these are used by LXC, OpenVZ, QEMU and Xen drivers.
The ESX, Hyper-V, Remote, Test & VirtualBox drivers all
implement the secondary drivers directly
* cpu/ - CPU feature management
* interface/ - Host network interface management
* network/ - Virtual NAT networking
* nwfilter/ - Network traffic filtering rules
* node_device/ - Host device enumeration
* secret/ - Secret management
* security/ - Mandatory access control drivers
* storage/ - Storage management drivers
Since both the hypervisor and secondary drivers can be built as
dlopen()able modules, it is *FORBIDDEN* to have build dependencies
between these directories. Drivers are only allowed to depend on
the public API, and the internal APIs in the util/ and conf/
directories