From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:48581) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adpWU-0005De-ND for qemu-devel@nongnu.org; Wed, 09 Mar 2016 20:36:19 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1adpWP-0006SO-Ny for qemu-devel@nongnu.org; Wed, 09 Mar 2016 20:36:18 -0500 Received: from mx1.redhat.com ([209.132.183.28]:60237) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1adpWP-0006SJ-II for qemu-devel@nongnu.org; Wed, 09 Mar 2016 20:36:13 -0500 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id 07F85BCFE7 for ; Thu, 10 Mar 2016 01:36:12 +0000 (UTC) Date: Thu, 10 Mar 2016 09:36:05 +0800 From: Peter Xu Message-ID: <20160310013605.GD4091@pxdev.xzpeter.org> References: <1457503418-31299-1-git-send-email-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1457503418-31299-1-git-send-email-peterx@redhat.com> Subject: Re: [Qemu-devel] [PATCH] qdict: fix unbounded stack for qdict_array_entries List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: Kevin Wolf , pbonzini@redhat.com, Markus Armbruster Sorry to forgot CCing Eric/Markus/Kevin. This patch title is not correct, which should be: "Fix unbounded stack warning for qdict_array_entries" Do I need to re-send with the same content? I'm using g_strdup_printf() here, considering it's most convenient, safe, and as long as it's called rarely only when quorum device opens. Thanks. Peter On Wed, Mar 09, 2016 at 02:03:38PM +0800, Peter Xu wrote: > Signed-off-by: Peter Xu > --- > qobject/qdict.c | 15 ++++++--------- > 1 file changed, 6 insertions(+), 9 deletions(-) > > diff --git a/qobject/qdict.c b/qobject/qdict.c > index 9833bd0..9188a87 100644 > --- a/qobject/qdict.c > +++ b/qobject/qdict.c > @@ -704,19 +704,16 @@ int qdict_array_entries(QDict *src, const char *subqdict) > for (i = 0; i < INT_MAX; i++) { > QObject *subqobj; > int subqdict_entries; > - size_t slen = 32 + subqdict_len; > - char indexstr[slen], prefix[slen]; > - size_t snprintf_ret; > + char *prefix = g_strdup_printf("%s%u.", subqdict, i); > > - snprintf_ret = snprintf(indexstr, slen, "%s%u", subqdict, i); > - assert(snprintf_ret < slen); > + subqdict_entries = qdict_count_prefixed_entries(src, prefix); > > - subqobj = qdict_get(src, indexstr); > + /* Remove ending "." */ > + prefix[strlen(prefix) - 1] = 0x00; > + subqobj = qdict_get(src, prefix); > > - snprintf_ret = snprintf(prefix, slen, "%s%u.", subqdict, i); > - assert(snprintf_ret < slen); > + g_free(prefix); > > - subqdict_entries = qdict_count_prefixed_entries(src, prefix); > if (subqdict_entries < 0) { > return subqdict_entries; > } > -- > 2.4.3 >