xen: fix memory corruption in legacy driver
authorJim Fehlig <jfehlig@suse.com>
Mon, 5 Aug 2013 16:27:23 +0000 (10:27 -0600)
committerDoug Goldstein <cardoe@cardoe.com>
Tue, 6 Aug 2013 14:26:53 +0000 (09:26 -0500)
commit673ff0d7ea937b104c67161843949e83b8080c3b
tree6ab22438fe6b56e2d749c401f8582bf5ef7ca343
parente9b8c9dc80ec53643824a054300f40d45219bf35
xen: fix memory corruption in legacy driver

Commit 632180d1 introduced memory corruption in xenDaemonListDefinedDomains
by starting to populate the names array at index -1, causing all sorts
of havoc in libvirtd such as aborts like the following

*** Error in `/usr/sbin/libvirtd': double free or corruption (out): 0x00007fffe00ccf20 ***
======= Backtrace: =========
/lib64/libc.so.6(+0x7abf6)[0x7ffff3fa0bf6]
/lib64/libc.so.6(+0x7b973)[0x7ffff3fa1973]
/lib64/libc.so.6(xdr_array+0xde)[0x7ffff403cbae]
/usr/sbin/libvirtd(+0x50251)[0x5555555a4251]
/lib64/libc.so.6(xdr_free+0x15)[0x7ffff403ccd5]
/usr/lib64/libvirt.so.0(+0x1fad34)[0x7ffff76b1d34]
/usr/lib64/libvirt.so.0(virNetServerProgramDispatch+0x1fc)[0x7ffff76b16f1]
/usr/lib64/libvirt.so.0(+0x1f214a)[0x7ffff76a914a]
/usr/lib64/libvirt.so.0(+0x1f222d)[0x7ffff76a922d]
/usr/lib64/libvirt.so.0(+0xbcc4f)[0x7ffff7573c4f]
/usr/lib64/libvirt.so.0(+0xbc5e5)[0x7ffff75735e5]
/lib64/libpthread.so.0(+0x7e0f)[0x7ffff48f7e0f]
/lib64/libc.so.6(clone+0x6d)[0x7ffff400e7dd]

Fix by initializing ret to 0 and only setting to error on failure path.
(cherry picked from commit 0e671a1646df543eab683b38f6644f70d12fbee1)
src/xen/xend_internal.c