Re: [libvirt] [PATCH] qemu_monitor_json.c: avoid many unconditional leaks

Daniel P. Berrange wrote: > On Wed, Jan 27, 2010 at 11:17:32AM +0100, Jim Meyering wrote: >> Daniel P. Berrange wrote: >> > On Wed, Jan 27, 2010 at 10:38:55AM +0100, Jim Meyering wrote: >> >> Actually, the preceding patch fixed only the one leak that had been >> >> introduced in the last month or so. Looking at the many other functions >> >> that do the same sort of thing (call qemuMonitorJSONMakeCommand, and >> >> later virJSONValueFree), I saw that they all had exactly the same leak. >> >> So this amended patch fixes all of them: >> >> >> >> >From 28f820354dcae9950cad042ea78a893fd9475830 Mon Sep 17 00:00:00 2001 >> >> From: Jim Meyering <meyering(a)redhat.com&gt; >> >> Date: Wed, 27 Jan 2010 09:58:12 +0100 >> >> Subject: [PATCH] qemu_monitor_json.c: avoid many unconditional leaks >> > >> > The real bug is the virJSONValueFree() itself which is missing >> > the final VIR_FREE(value) call. By doing the free in the caller, we >> > still leak data for compound array/hash values. >> >> Putting the VIR_FREE in virJSONValueFree was my first reflex, too, >> but since coverity detected no leak for the adjacent >> "virJSONValueFree(reply);" use, I assumed that doing so would >> cause a problem: >> >> virJSONValueFree(cmd); >> VIR_FREE(cmd); >> virJSONValueFree(reply); > > I think coverity must be confused then :-) The virJSONValueFree() method > is definitely intended to free any memory allocated during one of the > virJSONValueNewXXXX() methods. :-) In that case, here's a replacement patch: >From 96196ca0b0cd71ae6b7f2dd7668432db95678e70 Mon Sep 17 00:00:00 2001 From: Jim Meyering <meyering(a)redhat.com&gt; Date: Wed, 27 Jan 2010 09:58:12 +0100 Subject: [PATCH] json.c: avoid an unconditional leak from most qemuMonitorJSON* functions * src/util/json.c (virJSONValueFree): Free the "value" pointer, too. --- src/util/json.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/src/util/json.c b/src/util/json.c index a292e1b..1b3c359 100644 --- a/src/util/json.c +++ b/src/util/json.c @@ -2,7 +2,7 @@ * json.c: JSON object parsing/formatting * * Copyright (C) 2009 Daniel P. Berrange - * Copyright (C) 2009 Red Hat, Inc. + * Copyright (C) 2009-2010 Red Hat, Inc. * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public @@ -82,8 +82,9 @@ void virJSONValueFree(virJSONValuePtr value) case VIR_JSON_TYPE_NUMBER: VIR_FREE(value->data.number); break; - } + + VIR_FREE(value); }