From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:53965) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Wi351-00045u-S7 for qemu-devel@nongnu.org; Wed, 07 May 2014 10:44:25 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Wi34v-0008Fs-OQ for qemu-devel@nongnu.org; Wed, 07 May 2014 10:44:19 -0400 From: Marcel Apfelbaum Date: Wed, 7 May 2014 17:42:58 +0300 Message-Id: <1399473780-20374-3-git-send-email-marcel.a@redhat.com> In-Reply-To: <1399473780-20374-1-git-send-email-marcel.a@redhat.com> References: <1399473780-20374-1-git-send-email-marcel.a@redhat.com> Subject: [Qemu-devel] [PATCH 2/4] qapi: output visitor crashes qemu if it encounters a NULL value List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: mst@redhat.com, aik@ozlabs.ru, lcapitulino@redhat.com, blauwirbel@gmail.com, jcmvbkbc@gmail.com, edgar.iglesias@gmail.com, gxt@mprc.pku.edu.cn, proljc@gmail.com, agraf@suse.de, lersek@redhat.com, scottwood@freescale.com, borntraeger@de.ibm.com, hpoussin@reactos.org, aliguori@amazon.com, mdroth@linux.vnet.ibm.com, chouteau@adacore.com, jan.kiszka@web.de, stefanha@redhat.com, pbonzini@redhat.com, cornelia.huck@de.ibm.com, peter.crosthwaite@xilinx.com, mark.langsdorf@calxeda.com, armbru@redhat.com, michael@walle.cc, qemu-ppc@nongnu.org, peter.chubb@nicta.com.au, afaerber@suse.de, aurelien@aurel32.net A NULL value is not added to visitor's stack, but there is no check for that when the visitor tries to return that value, leading to Qemu crash. Reviewed-by: Eric Blake Signed-off-by: Marcel Apfelbaum --- qapi/qmp-output-visitor.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/qapi/qmp-output-visitor.c b/qapi/qmp-output-visitor.c index 74a5684..0562f49 100644 --- a/qapi/qmp-output-visitor.c +++ b/qapi/qmp-output-visitor.c @@ -66,6 +66,11 @@ static QObject *qmp_output_pop(QmpOutputVisitor *qov) static QObject *qmp_output_first(QmpOutputVisitor *qov) { QStackEntry *e = QTAILQ_LAST(&qov->stack, QStack); + + if (!e) { + return NULL; + } + return e->value; } -- 1.8.3.1