[Libvir] [PATCH] avoid virsh hang due to missing virDomainFree(dom) call

Without the following patch, this command would hang printf 'domuuid fc4\ndomstate fc4\n' \ | ./virsh --connect test://$PWD/../docs/testnode.xml with this stack trace: __lll_lock_wait ... _L_lock_105 ... __pthread_mutex_lock ... virUnrefDomain (domain=0x6a8b30) at hash.c:884 virDomainFree (domain=0x6a8b30) at libvirt.c:1211 cmdDomstate (ctl=0x7fffea723390, cmd=0x6a8b10) at virsh.c:677 vshCommandRun (ctl=0x7fffea723390, cmd=0x6a8b10) at virsh.c:4033 main (argc=3, argv=0x7fffea7234e8) at virsh.c:5015 The problem is that cmdDomuuid didn't call virDomainFree(dom), so cmdDomstate hangs trying to do the Unref. I then did a mind-numbing audit of all of the other cmd* functions in virsh.c and found two other cases in which a "dom" may not be released. Here's the patch: Avoid virsh hang due to missing virDomainFree(dom) calls * src/virsh.c (cmdDomuuid): Add missing virDomainFree call. (cmdAttachDevice): Likewise. (cmdDetachDevice): Likewise. --- src/virsh.c | 9 +++++++-- 1 files changed, 7 insertions(+), 2 deletions(-) diff --git a/src/virsh.c b/src/virsh.c index 0d93fb6..487f256 100644 --- a/src/virsh.c +++ b/src/virsh.c @@ -2161,6 +2161,7 @@ cmdDomuuid(vshControl * ctl, vshCmd * cmd) else vshError(ctl, FALSE, "%s", _("failed to get domain UUID")); + virDomainFree(dom); return TRUE; } @@ -3038,8 +3039,10 @@ cmdAttachDevice(vshControl * ctl, vshCmd * cmd) return FALSE; } - if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) + if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) { + virDomainFree(dom); return FALSE; + } ret = virDomainAttachDevice(dom, buffer); free (buffer); @@ -3092,8 +3095,10 @@ cmdDetachDevice(vshControl * ctl, vshCmd * cmd) return FALSE; } - if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) + if (virFileReadAll(from, VIRSH_MAX_XML_FILE, &buffer) < 0) { + virDomainFree(dom); return FALSE; + } ret = virDomainDetachDevice(dom, buffer); free (buffer); -- 1.5.4.rc5.1.g0fa73