From mboxrd@z Thu Jan 1 00:00:00 1970 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 From: Date: Fri, 24 Jun 2011 17:35:48 +0100 Message-ID: <1308933348-12022-1-git-send-email-stefano.stabellini@eu.citrix.com> MIME-Version: 1.0 Content-Type: text/plain Subject: [Qemu-devel] [PATCH v2] xen_disk: cope with missing xenstore "params" node List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: qemu-devel@nongnu.org Cc: xen-devel@lists.xensource.com, agraf@suse.de, Stefano Stabellini 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) -- 1.7.2.3