From patchwork Fri Jun 24 16:35:48 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefano Stabellini X-Patchwork-Id: 101828 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [140.186.70.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id 2F2E0B6F7E for ; Sat, 25 Jun 2011 02:55:34 +1000 (EST) Received: from localhost ([::1]:43615 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qa9fG-0002em-Ta for incoming@patchwork.ozlabs.org; Fri, 24 Jun 2011 12:55:31 -0400 Received: from eggs.gnu.org ([140.186.70.92]:45114) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qa9IV-0005Np-Ck for qemu-devel@nongnu.org; Fri, 24 Jun 2011 12:32:00 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Qa9IB-0003lt-QV for qemu-devel@nongnu.org; Fri, 24 Jun 2011 12:31:58 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:61243) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Qa9IB-0003k8-Ff for qemu-devel@nongnu.org; Fri, 24 Jun 2011 12:31:39 -0400 X-IronPort-AV: E=Sophos;i="4.65,420,1304308800"; d="scan'208";a="152563684" Received: from ftlpmailmx02.citrite.net ([10.13.107.66]) by FTLPIPO02.CITRIX.COM with ESMTP/TLS/RC4-MD5; 24 Jun 2011 12:31:38 -0400 Received: from smtp01.ad.xensource.com (10.219.128.104) by smtprelay.citrix.com (10.13.107.66) with Microsoft SMTP Server id 8.3.137.0; Fri, 24 Jun 2011 12:31:38 -0400 Received: from localhost.localdomain (kaball.uk.xensource.com [10.80.2.59]) by smtp01.ad.xensource.com (8.13.1/8.13.1) with ESMTP id p5OGVUO3024733; Fri, 24 Jun 2011 09:31:31 -0700 From: To: qemu-devel@nongnu.org Date: Fri, 24 Jun 2011 17:35:48 +0100 Message-ID: <1308933348-12022-1-git-send-email-stefano.stabellini@eu.citrix.com> X-Mailer: git-send-email 1.7.0.4 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 66.165.176.63 Cc: xen-devel@lists.xensource.com, agraf@suse.de, Stefano Stabellini Subject: [Qemu-devel] [PATCH v2] xen_disk: cope with missing xenstore "params" node 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 From: Stefano Stabellini When disk is a cdrom and the drive is empty the "params" node in xenstore might be missing completely: cope with it instead of segfaulting. Updated in v2: - actually removed the strchr(blkdev->params, ':') that caused the segfault; - free all the allocated strings from xenstore before returning; Signed-off-by: Stefano Stabellini --- hw/xen_disk.c | 29 ++++++++++++++++++++++------- 1 files changed, 22 insertions(+), 7 deletions(-) diff --git a/hw/xen_disk.c b/hw/xen_disk.c index 096d1c9..eec05dd 100644 --- a/hw/xen_disk.c +++ b/hw/xen_disk.c @@ -616,12 +616,14 @@ static int blk_init(struct XenDevice *xendev) { struct XenBlkDev *blkdev = container_of(xendev, struct XenBlkDev, xendev); int index, qflags, have_barriers, info = 0; - char *h; /* read xenstore entries */ if (blkdev->params == NULL) { + char *h = NULL; blkdev->params = xenstore_read_be_str(&blkdev->xendev, "params"); - h = strchr(blkdev->params, ':'); + if (blkdev->params != NULL) { + h = strchr(blkdev->params, ':'); + } if (h != NULL) { blkdev->fileproto = blkdev->params; blkdev->filename = h+1; @@ -649,7 +651,7 @@ static int blk_init(struct XenDevice *xendev) blkdev->mode == NULL || blkdev->type == NULL || blkdev->dev == NULL) { - return -1; + goto out_error; } /* read-only ? */ @@ -672,10 +674,15 @@ static int blk_init(struct XenDevice *xendev) /* setup via xenbus -> create new block driver instance */ xen_be_printf(&blkdev->xendev, 2, "create new bdrv (xenbus setup)\n"); blkdev->bs = bdrv_new(blkdev->dev); - if (bdrv_open(blkdev->bs, blkdev->filename, qflags, - bdrv_find_whitelisted_format(blkdev->fileproto)) != 0) { - bdrv_delete(blkdev->bs); - return -1; + if (blkdev->bs) { + if (bdrv_open(blkdev->bs, blkdev->filename, qflags, + bdrv_find_whitelisted_format(blkdev->fileproto)) != 0) { + bdrv_delete(blkdev->bs); + blkdev->bs = NULL; + } + } + if (!blkdev->bs) { + goto out_error; } } else { /* setup via qemu cmdline -> already setup for us */ @@ -704,6 +711,14 @@ static int blk_init(struct XenDevice *xendev) xenstore_write_be_int(&blkdev->xendev, "sectors", blkdev->file_size / blkdev->file_blk); return 0; + +out_error: + qemu_free(blkdev->params); + qemu_free(blkdev->mode); + qemu_free(blkdev->type); + qemu_free(blkdev->dev); + qemu_free(blkdev->devtype); + return -1; } static int blk_connect(struct XenDevice *xendev)