https://bugzilla.redhat.com/show_bug.cgi?id=1434882 Imagine the following scenario: 1) virsh net-start default 2) virsh start myFavouriteDomain 3) virsh net-destroy default 4) virsh destroy myFavouriteDomain (assuming myFavouriteDomain has an interface from default network) Regardless of how unlikely this scenario looks like, we should not crash. The problem is, on net-destroy in networkShutdownNetworkVirtual() the virMacMap module is unrefed, but the stale pointer is kept around. Thus when the domain destroy procedure comes in, networkReleaseActualDevice() and subsequently networkMacMgrDel() is called. This function sees the stale pointer and starts calling the virMacMap module APIs which work over freed memory. Signed-off-by: Michal Privoznik <mprivozn@xxxxxxxxxx> --- src/network/bridge_driver.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/network/bridge_driver.c b/src/network/bridge_driver.c index 0ea8e2348..3fcdd702e 100644 --- a/src/network/bridge_driver.c +++ b/src/network/bridge_driver.c @@ -2488,7 +2488,8 @@ networkShutdownNetworkVirtual(virNetworkDriverStatePtr driver, if (network->def->bandwidth) virNetDevBandwidthClear(network->def->bridge); - virObjectUnref(network->macmap); + if (!virObjectUnref(network->macmap)) + network->macmap = NULL; if (network->radvdPid > 0) { char *radvdpidbase; -- 2.11.0 -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list
