[libvirt] [PATCH 1/1] Fix the crash when seclable is freed

[Li Zhang]

From: Li Zhang <zhlcindy at linux.vnet.ibm.com>

When seclabel's type is VIR_DOMAIN_SECLABEL_NONE,
virSecurityLabelDefPtr's members are not allocated.
So it will cause crash when calling VIR_FREE.

This problem is found when running autotest on PPC.

 Failed to remove cgroup for virt-tests-vm1
 *** glibc detected *** /usr/sbin/libvirtd: free(): invalid pointer: 0x00003fff9c187510 ***
 ======= Backtrace: =========
 /lib64/libc.so.6(+0xb89c4)[0x3fffa9bc89c4]
 /lib64/libvirt.so.0(virFree-0x3e2320)[0x3fffaa82e9c0]
 /lib64/libvirt.so.0(virSecurityLabelDefFree-0x378984)[0x3fffaa89d69c]
 /lib64/libvirt.so.0(virDomainDefFree-0x367c98)[0x3fffaa8ae968]
 /usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so(qemuProcessStop-0xc85f8)[0x3fffa2899d58]
 /usr/lib64/libvirt/connection-driver/libvirt_driver_qemu.so(+0xc3668)[0x3fffa28e3668]
 /lib64/libvirt.so.0(virDomainDestroy-0x309bd0)[0x3fffaa90f6f0]
 /usr/sbin/libvirtd[0x10035230]
 /lib64/libvirt.so.0(virNetServerProgramDispatch-0x289b50)[0x3fffaa995930]
 /lib64/libvirt.so.0(+0x20db18)[0x3fffaa98db18]
 /lib64/libvirt.so.0(+0xfbd24)[0x3fffaa87bd24]
 /lib64/libvirt.so.0(+0xfaec8)[0x3fffaa87aec8]
 /lib64/libpthread.so.0(+0xc604)[0x3fffa9d7c604]
 /lib64/libc.so.6(clone-0xb8fe4)[0x3fffa9c3f094]

Signed-off-by: Li Zhang <zhlcindy at linux.vnet.ibm.com>
---
 src/conf/domain_conf.c |    2 ++
 1 files changed, 2 insertions(+), 0 deletions(-)

diff --git a/src/conf/domain_conf.c b/src/conf/domain_conf.c
index f3fca7f..2856660 100644
--- a/src/conf/domain_conf.c
+++ b/src/conf/domain_conf.c
@@ -1006,6 +1006,8 @@ virSecurityLabelDefFree(virSecurityLabelDefPtr def)
 {
     if (!def)
         return;
+    if (def->type == VIR_DOMAIN_SECLABEL_NONE)
+        return;
     VIR_FREE(def->model);
     VIR_FREE(def->label);
     VIR_FREE(def->imagelabel);
-- 
1.7.5.4