From 91e1bb748bcc9fb1737eacb1c26abd62a2ae7076 Mon Sep 17 00:00:00 2001 From: Zhouyang Jia Date: Sat, 16 Jun 2018 01:05:01 +0800 Subject: [PATCH] scsi: xen-scsifront: add error handling for xenbus_printf [ Upstream commit 93efbd39870474cc536b9caf4a6efeb03b0bc56f ] When xenbus_printf fails, the lack of error-handling code may cause unexpected results. This patch adds error-handling code after calling xenbus_printf. Signed-off-by: Zhouyang Jia Reviewed-by: Juergen Gross Signed-off-by: Juergen Gross Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/xen-scsifront.c | 33 ++++++++++++++++++++++++++------- 1 file changed, 26 insertions(+), 7 deletions(-) diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c index 36f59a1be7e9..61389bdc7926 100644 --- a/drivers/scsi/xen-scsifront.c +++ b/drivers/scsi/xen-scsifront.c @@ -654,10 +654,17 @@ static int scsifront_dev_reset_handler(struct scsi_cmnd *sc) static int scsifront_sdev_configure(struct scsi_device *sdev) { struct vscsifrnt_info *info = shost_priv(sdev->host); + int err; - if (info && current == info->curr) - xenbus_printf(XBT_NIL, info->dev->nodename, + if (info && current == info->curr) { + err = xenbus_printf(XBT_NIL, info->dev->nodename, info->dev_state_path, "%d", XenbusStateConnected); + if (err) { + xenbus_dev_error(info->dev, err, + "%s: writing dev_state_path", __func__); + return err; + } + } return 0; } @@ -665,10 +672,15 @@ static int scsifront_sdev_configure(struct scsi_device *sdev) static void scsifront_sdev_destroy(struct scsi_device *sdev) { struct vscsifrnt_info *info = shost_priv(sdev->host); + int err; - if (info && current == info->curr) - xenbus_printf(XBT_NIL, info->dev->nodename, + if (info && current == info->curr) { + err = xenbus_printf(XBT_NIL, info->dev->nodename, info->dev_state_path, "%d", XenbusStateClosed); + if (err) + xenbus_dev_error(info->dev, err, + "%s: writing dev_state_path", __func__); + } } static struct scsi_host_template scsifront_sht = { @@ -1003,9 +1015,12 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op) if (scsi_add_device(info->host, chn, tgt, lun)) { dev_err(&dev->dev, "scsi_add_device\n"); - xenbus_printf(XBT_NIL, dev->nodename, + err = xenbus_printf(XBT_NIL, dev->nodename, info->dev_state_path, "%d", XenbusStateClosed); + if (err) + xenbus_dev_error(dev, err, + "%s: writing dev_state_path", __func__); } break; case VSCSIFRONT_OP_DEL_LUN: @@ -1019,10 +1034,14 @@ static void scsifront_do_lun_hotplug(struct vscsifrnt_info *info, int op) } break; case VSCSIFRONT_OP_READD_LUN: - if (device_state == XenbusStateConnected) - xenbus_printf(XBT_NIL, dev->nodename, + if (device_state == XenbusStateConnected) { + err = xenbus_printf(XBT_NIL, dev->nodename, info->dev_state_path, "%d", XenbusStateConnected); + if (err) + xenbus_dev_error(dev, err, + "%s: writing dev_state_path", __func__); + } break; default: break;