From patchwork Wed Feb 24 08:08:08 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Fam Zheng X-Patchwork-Id: 587230 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 E6B8B140BEA for ; Wed, 24 Feb 2016 19:08:34 +1100 (AEDT) Received: from localhost ([::1]:34204 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aYUUq-0003Cl-T0 for incoming@patchwork.ozlabs.org; Wed, 24 Feb 2016 03:08:32 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43976) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aYUUb-0002uO-Ue for qemu-devel@nongnu.org; Wed, 24 Feb 2016 03:08:18 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1aYUUX-0002jD-T0 for qemu-devel@nongnu.org; Wed, 24 Feb 2016 03:08:17 -0500 Received: from mx1.redhat.com ([209.132.183.28]:59370) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1aYUUX-0002j9-O6 for qemu-devel@nongnu.org; Wed, 24 Feb 2016 03:08:13 -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 6D5EDC003588 for ; Wed, 24 Feb 2016 08:08:13 +0000 (UTC) Received: from fam-t430.nay.redhat.com (dhcp-15-42.nay.redhat.com [10.66.15.42]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u1O889wd024644; Wed, 24 Feb 2016 03:08:11 -0500 From: Fam Zheng To: qemu-devel@nongnu.org Date: Wed, 24 Feb 2016 16:08:08 +0800 Message-Id: <1456301288-1592-1-git-send-email-famz@redhat.com> X-Scanned-By: MIMEDefang 2.68 on 10.5.11.22 X-detected-operating-system: by eggs.gnu.org: GNU/Linux 3.x X-Received-From: 209.132.183.28 Cc: Gerd Hoffmann Subject: [Qemu-devel] [PATCH] usb-redirect: Avoid double free of data 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 If dropping packets, data is freed, the caller's loop should not continue. Reported by ccc-analyzer. Signed-off-by: Fam Zheng --- hw/usb/redirect.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/hw/usb/redirect.c b/hw/usb/redirect.c index d0f7cb8..38a5393 100644 --- a/hw/usb/redirect.c +++ b/hw/usb/redirect.c @@ -447,7 +447,7 @@ static USBPacket *usbredir_find_packet_by_id(USBRedirDevice *dev, return p; } -static void bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, +static int bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, uint8_t status, uint8_t ep, void *free_on_destroy) { struct buf_packet *bufp; @@ -464,7 +464,7 @@ static void bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, if (dev->endpoint[EP2I(ep)].bufpq_size > dev->endpoint[EP2I(ep)].bufpq_target_size) { free(data); - return; + return -1; } dev->endpoint[EP2I(ep)].bufpq_dropping_packets = 0; } @@ -477,6 +477,7 @@ static void bufp_alloc(USBRedirDevice *dev, uint8_t *data, uint16_t len, bufp->free_on_destroy = free_on_destroy; QTAILQ_INSERT_TAIL(&dev->endpoint[EP2I(ep)].bufpq, bufp, next); dev->endpoint[EP2I(ep)].bufpq_size++; + return 0; } static void bufp_free(USBRedirDevice *dev, struct buf_packet *bufp, @@ -2082,13 +2083,17 @@ static void usbredir_buffered_bulk_packet(void *priv, uint64_t id, status = usb_redir_success; free_on_destroy = NULL; for (i = 0; i < data_len; i += len) { + int r; if (len >= (data_len - i)) { len = data_len - i; status = buffered_bulk_packet->status; free_on_destroy = data; } /* bufp_alloc also adds the packet to the ep queue */ - bufp_alloc(dev, data + i, len, status, ep, free_on_destroy); + r = bufp_alloc(dev, data + i, len, status, ep, free_on_destroy); + if (r) { + break; + } } if (dev->endpoint[EP2I(ep)].pending_async_packet) {