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0e3c68acd8
The following is a long winded way to say this patch is avoiding a false positive. Coverity complains that calling networkPlugBandwidth() could eventually end up with a NULL dereference on iface->bandwidth because in the networkAllocateActualDevice there's a check of 'iface->bandwidth' before deciding to try to use the 'portgroup' if it exists or to not perferm the virNetDevBandwidthCopy if 'bandwidth' is not NULL. Later in networkPlugBandwidth the 'iface->bandwidth' is sourced from virDomainNetGetActualBandwidth - which would be either iface->bandwidth or (preferably) iface->data.network.actual->bandwidth which would have been filled in from either 'iface->bandwidth' or 'portgroup->bandwidth' back in networkAllocateActualDevice There *is* a check in networkCheckBandwidth for the result of the virDomainNetGetActualBandwidth being NULL and a return 1 based on that which would cause networkPlugBandwidth to exit properly and thus never hit the condition that Coverity complains about. However, since Coverity checks all paths - it somehow believes that a return of 0 by networkCheckBandwidth in this condition would end up causing the possible NULL dereference. The "fix" to silence Coverity is to not have networkCheckBandwidth also call virDomainNetGetActualBandwidth in order to get the ifaceBand, but rather have it accept it as an argument which causes Coverity to "see" that it's the exit condition of 1 that won't have the possible NULL dereference. Since we're passing that, I added the passing of iface->mac rather than passing iface as well. This just hopefully makes sure someone doesn't undo this in the future...
LibVirt : simple API for virtualization
Libvirt is a C toolkit to interact with the virtualization capabilities
of recent versions of Linux (and other OSes). It is free software
available under the GNU Lesser General Public License. Virtualization of
the Linux Operating System means the ability to run multiple instances of
Operating Systems concurrently on a single hardware system where the basic
resources are driven by a Linux instance. The library aim at providing
long term stable C API initially for the Xen paravirtualization but
should be able to integrate other virtualization mechanisms if needed.
Daniel Veillard <veillard@redhat.com>