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8.92. libnl

Updated libnl packages that fix several bugs are now available for Red Hat Enterprise Linux 6.
The libnl packages contain a convenience library to simplify using the Linux kernel's Netlink sockets interface for network manipulation.

Bug Fixes

When a domain was started using the libvirt client libraries and utilities, a memory leak was triggered from the libnl library because libnl continued to use memory that was no longer in use. With this update, memory leaks in libnl are fixed, and libnl releases memory after it completes its usage.
Prior to this update, libnl's error handling made generous use of the strerror() function. Nevertheless, the strerror() function was not threadsafe, and it was possible for multiple threads in an application to call libnl. With this update, all the occurrences of strerror() are replaced with a call to the strerror_r() function that puts the message into a thread-local static buffer.
When the max_vfs parameter of the igb module, which allocates the maximum number of Virtual Functions, was set to any value greater than 50,50 on a KVM (Kernel-based Virtual Machine) host, the guest failed to start with the following error messages:
error : virNetDevParseVfConfig:1484 : internal error missing IFLA_VF_INFO in netlink response
error : virFileReadAll:457 : Failed to open file '/var/run/libvirt/qemu/eth0_vf0': No such file or directory error : virFileReadAll:457 : Failed to open file '/var/run/libvirt/qemu/eth1_vf0': No such file or directory
This update increases the default receive buffer size to allow receiving of Netlink messages that exceed the size of a memory page. Thus, guests are able to start on the KVM host, and error messages no longer occur in the described scenario.
Users of libnl are advised to upgrade to these updated packages, which fix these bugs.