[PATCH] qemu: Fix potential crash during driver cleanup
During qemu driver shutdown, objects are freed in qemuStateCleanup that
could still be used by active worker threads, resulting in crashes. E.g.
a worker thread could be processing a monitor EOF event after the
security manager is already disposed
Program terminated with signal SIGSEGV, Segmentation fault.
#0 0x00007fd9a9a1e1fe in virSecurityManagerMoveImageMetadata (mgr=0x7fd948012160, pid=-1,
src=src@entry=0x7fd98c072c90, dst=dst@entry=0x0)
at ../../src/security/security_manager.c:468
#1 0x00007fd9646ff0f0 in qemuSecurityMoveImageMetadata
(driver=driver@entry=0x7fd948043830, vm=vm@entry=0x7fd98c066db0,
src=src@entry=0x7fd98c072c90,
dst=dst@entry=0x0) at ../../src/qemu/qemu_security.c:182
#2 0x00007fd96462c7b0 in qemuBlockRemoveImageMetadata
(driver=driver@entry=0x7fd948043830, vm=vm@entry=0x7fd98c066db0, diskTarget=0x7fd98c072530
"vda",
src=<optimized out>) at ../../src/qemu/qemu_block.c:2628
#3 0x00007fd9646929d6 in qemuProcessStop (driver=driver@entry=0x7fd948043830,
vm=vm@entry=0x7fd98c066db0, reason=reason@entry=VIR_DOMAIN_SHUTOFF_SHUTDOWN,
asyncJob=asyncJob@entry=QEMU_ASYNC_JOB_NONE, flags=<optimized out>) at
../../src/qemu/qemu_process.c:7585
#4 0x00007fd9646fc842 in processMonitorEOFEvent (vm=0x7fd98c066db0,
driver=0x7fd948043830) at ../../src/qemu/qemu_driver.c:4794
#5 qemuProcessEventHandler (data=0x561a93febb60, opaque=0x7fd948043830) at
../../src/qemu/qemu_driver.c:4900
#6 0x00007fd9a9971a31 in virThreadPoolWorker (opaque=opaque@entry=0x561a93fb58e0) at
../../src/util/virthreadpool.c:163
(gdb) p mgr->drv
$2 = (virSecurityDriverPtr) 0x0
Prior to commit 7cf76d4e3ab, the worker thread pool was freed before
disposing any driver objects. Let's return to that pattern, but leave
the other changes made by 7cf76d4e3ab.
Signed-off-by: Jim Fehlig <jfehlig(a)suse.com>
---
src/qemu/qemu_driver.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/qemu/qemu_driver.c b/src/qemu/qemu_driver.c
index b4fb7ec1df..28e470e4a2 100644
--- a/src/qemu/qemu_driver.c
+++ b/src/qemu/qemu_driver.c
@@ -1062,6 +1062,7 @@ qemuStateCleanup(void)
if (!qemu_driver)
return -1;
+ virThreadPoolFree(qemu_driver->workerPool);
virObjectUnref(qemu_driver->migrationErrors);
virLockManagerPluginUnref(qemu_driver->lockManager);
virSysinfoDefFree(qemu_driver->hostsysinfo);
@@ -1078,7 +1079,6 @@ qemuStateCleanup(void)
ebtablesContextFree(qemu_driver->ebtables);
VIR_FREE(qemu_driver->qemuImgBinary);
virObjectUnref(qemu_driver->domains);
- virThreadPoolFree(qemu_driver->workerPool);
if (qemu_driver->lockFD != -1)
virPidFileRelease(qemu_driver->config->stateDir, "driver",
qemu_driver->lockFD);
--
2.40.0