$ MALLOC_PERTURB_=234 qemu-system-x86_64 -vnc :0,acl,sasl [...]
QEMU 0.15.50 monitor - type 'help' for more information
(qemu) acl_add vnc.username fred allow
acl: added rule at position 1
(qemu) acl_reset vnc.username
Segmentation fault (core dumped)
Spotted by Coverity.
Signed-off-by: Markus Armbruster <armbru@redhat.com> Signed-off-by: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>