From patchwork Wed Jul 9 08:05:47 2014 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Hajnoczi X-Patchwork-Id: 368787 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [IPv6:2001:4830:134:3::11]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 5966A14011B for ; Fri, 11 Jul 2014 06:51:39 +1000 (EST) Received: from localhost ([::1]:40169 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X5LJZ-0000tp-NW for incoming@patchwork.ozlabs.org; Thu, 10 Jul 2014 16:51:37 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60143) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4nDp-0000Jy-Ra for qemu-devel@nongnu.org; Wed, 09 Jul 2014 04:27:32 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1X4nDj-0008Nu-MQ for qemu-devel@nongnu.org; Wed, 09 Jul 2014 04:27:25 -0400 Received: from mx1.redhat.com ([209.132.183.28]:13142) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1X4nDj-0008Nc-Cu for qemu-devel@nongnu.org; Wed, 09 Jul 2014 04:27:19 -0400 Received: from int-mx10.intmail.prod.int.phx2.redhat.com (int-mx10.intmail.prod.int.phx2.redhat.com [10.5.11.23]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id s698RCuP028200 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 9 Jul 2014 04:27:13 -0400 Received: from localhost (ovpn-112-31.ams2.redhat.com [10.36.112.31]) by int-mx10.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id s6985tl8011575; Wed, 9 Jul 2014 04:05:56 -0400 From: Stefan Hajnoczi To: Date: Wed, 9 Jul 2014 10:05:47 +0200 Message-Id: <1404893149-27701-3-git-send-email-stefanha@redhat.com> In-Reply-To: <1404893149-27701-1-git-send-email-stefanha@redhat.com> References: <1404893149-27701-1-git-send-email-stefanha@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.23 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Kevin Wolf , Fam Zheng , ming.lei@canonical.com, Christian Borntraeger , Stefan Hajnoczi , Paolo Bonzini Subject: [Qemu-devel] [PATCH v3 2/4] dataplane: do not free VirtQueueElement in vring_push() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.14 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org VirtQueueElement is allocated in vring_pop() so it seems to make sense that vring_push() should free it. Alas, virtio-blk frees VirtQueueElement itself in virtio_blk_free_request(). This patch solves a double-free assertion in glib's g_slice_free(). Rename vring_free_element() to vring_unmap_element() since it no longer frees the VirtQueueElement. Signed-off-by: Stefan Hajnoczi Tested-by: Christian Borntraeger --- hw/virtio/dataplane/vring.c | 9 ++++----- include/hw/virtio/dataplane/vring.h | 1 - 2 files changed, 4 insertions(+), 6 deletions(-) diff --git a/hw/virtio/dataplane/vring.c b/hw/virtio/dataplane/vring.c index 665a1ff..5d17d39 100644 --- a/hw/virtio/dataplane/vring.c +++ b/hw/virtio/dataplane/vring.c @@ -272,7 +272,7 @@ static int get_indirect(Vring *vring, VirtQueueElement *elem, return 0; } -void vring_free_element(VirtQueueElement *elem) +static void vring_unmap_element(VirtQueueElement *elem) { int i; @@ -287,8 +287,6 @@ void vring_free_element(VirtQueueElement *elem) for (i = 0; i < elem->in_num; i++) { vring_unmap(elem->in_sg[i].iov_base, true); } - - g_slice_free(VirtQueueElement, elem); } /* This looks in the virtqueue and for the first available buffer, and converts @@ -402,7 +400,8 @@ out: vring->broken = true; } if (elem) { - vring_free_element(elem); + vring_unmap_element(elem); + g_slice_free(VirtQueueElement, elem); } *p_elem = NULL; return ret; @@ -418,7 +417,7 @@ void vring_push(Vring *vring, VirtQueueElement *elem, int len) unsigned int head = elem->index; uint16_t new; - vring_free_element(elem); + vring_unmap_element(elem); /* Don't touch vring if a fatal error occurred */ if (vring->broken) { diff --git a/include/hw/virtio/dataplane/vring.h b/include/hw/virtio/dataplane/vring.h index 63e7bf4..b23edd2 100644 --- a/include/hw/virtio/dataplane/vring.h +++ b/include/hw/virtio/dataplane/vring.h @@ -55,6 +55,5 @@ bool vring_enable_notification(VirtIODevice *vdev, Vring *vring); bool vring_should_notify(VirtIODevice *vdev, Vring *vring); int vring_pop(VirtIODevice *vdev, Vring *vring, VirtQueueElement **elem); void vring_push(Vring *vring, VirtQueueElement *elem, int len); -void vring_free_element(VirtQueueElement *elem); #endif /* VRING_H */