diff mbox

[v4] scsi: xen-scsifront: add error handling for xenbus_printf

Message ID 1529027312-56770-1-git-send-email-jiazhouyang09@gmail.com (mailing list archive)
State Superseded
Headers show

Commit Message

Zhouyang Jia June 15, 2018, 1:48 a.m. UTC
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 <jiazhouyang09@gmail.com>
---
v1->v2:
- Fix dereferencing before checking.
v2->v3:
- Use xenbus_dev_error to report errors.
v3->v4:
- Fix compilation errors.
---
 drivers/scsi/xen-scsifront.c | 33 ++++++++++++++++++++++++++-------
 1 file changed, 26 insertions(+), 7 deletions(-)

Comments

kernel test robot June 15, 2018, 6:04 a.m. UTC | #1
Hi,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on xen-tip/linux-next]
[also build test WARNING on v4.17 next-20180614]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/linux-kernel-owner-vger-kernel-org/scsi-xen-scsifront-add-error-handling-for-xenbus_printf/20180615-094919
base:   https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next
reproduce:
        # apt-get install sparse
        make ARCH=x86_64 allmodconfig
        make C=1 CF=-D__CHECK_ENDIAN__


sparse warnings: (new ones prefixed by >>)

   drivers/scsi/xen-scsifront.c:267:21: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:440:33: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:440:33: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:473:33: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:473:33: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:474:33: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:474:33: sparse: expression using sizeof(void)
>> drivers/scsi/xen-scsifront.c:663:43: sparse: incorrect type in argument 1 (different base types) @@    expected struct xenbus_device *dev @@    got sstruct xenbus_device *dev @@
   drivers/scsi/xen-scsifront.c:663:43:    expected struct xenbus_device *dev
   drivers/scsi/xen-scsifront.c:663:43:    got struct xenbus_device **<noident>
   drivers/scsi/xen-scsifront.c:681:43: sparse: incorrect type in argument 1 (different base types) @@    expected struct xenbus_device *dev @@    got sstruct xenbus_device *dev @@
   drivers/scsi/xen-scsifront.c:681:43:    expected struct xenbus_device *dev
   drivers/scsi/xen-scsifront.c:681:43:    got struct xenbus_device **<noident>
   drivers/scsi/xen-scsifront.c:1063:19: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:1064:19: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c:1065:19: sparse: expression using sizeof(void)
   drivers/scsi/xen-scsifront.c: In function 'scsifront_sdev_configure':
   drivers/scsi/xen-scsifront.c:663:21: error: passing argument 1 of 'xenbus_dev_error' from incompatible pointer type [-Werror=incompatible-pointer-types]
       xenbus_dev_error(&info->dev, err,
                        ^
   In file included from drivers/scsi/xen-scsifront.c:50:0:
   include/xen/xenbus.h:224:6: note: expected 'struct xenbus_device *' but argument is of type 'struct xenbus_device **'
    void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
         ^~~~~~~~~~~~~~~~
   drivers/scsi/xen-scsifront.c: In function 'scsifront_sdev_destroy':
   drivers/scsi/xen-scsifront.c:681:21: error: passing argument 1 of 'xenbus_dev_error' from incompatible pointer type [-Werror=incompatible-pointer-types]
       xenbus_dev_error(&info->dev, err,
                        ^
   In file included from drivers/scsi/xen-scsifront.c:50:0:
   include/xen/xenbus.h:224:6: note: expected 'struct xenbus_device *' but argument is of type 'struct xenbus_device **'
    void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
         ^~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors

vim +663 drivers/scsi/xen-scsifront.c

   653	
   654	static int scsifront_sdev_configure(struct scsi_device *sdev)
   655	{
   656		struct vscsifrnt_info *info = shost_priv(sdev->host);
   657		int err;
   658	
   659		if (info && current == info->curr) {
   660			err = xenbus_printf(XBT_NIL, info->dev->nodename,
   661				      info->dev_state_path, "%d", XenbusStateConnected);
   662			if (err) {
 > 663				xenbus_dev_error(&info->dev, err,
   664					"%s: writing dev_state_path", __func__);
   665				return err;
   666			}
   667		}
   668	
   669		return 0;
   670	}
   671	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
kernel test robot June 15, 2018, 11:59 a.m. UTC | #2
Hi,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on xen-tip/linux-next]
[also build test ERROR on v4.17 next-20180615]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/linux-kernel-owner-vger-kernel-org/scsi-xen-scsifront-add-error-handling-for-xenbus_printf/20180615-094919
base:   https://git.kernel.org/pub/scm/linux/kernel/git/xen/tip.git linux-next
config: x86_64-fedora-25 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-16) 7.3.0
reproduce:
        # save the attached .config to linux build tree
        make ARCH=x86_64 

All errors (new ones prefixed by >>):

   drivers//scsi/xen-scsifront.c: In function 'scsifront_sdev_configure':
>> drivers//scsi/xen-scsifront.c:663:21: error: passing argument 1 of 'xenbus_dev_error' from incompatible pointer type [-Werror=incompatible-pointer-types]
       xenbus_dev_error(&info->dev, err,
                        ^
   In file included from drivers//scsi/xen-scsifront.c:50:0:
   include/xen/xenbus.h:224:6: note: expected 'struct xenbus_device *' but argument is of type 'struct xenbus_device **'
    void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
         ^~~~~~~~~~~~~~~~
   drivers//scsi/xen-scsifront.c: In function 'scsifront_sdev_destroy':
   drivers//scsi/xen-scsifront.c:681:21: error: passing argument 1 of 'xenbus_dev_error' from incompatible pointer type [-Werror=incompatible-pointer-types]
       xenbus_dev_error(&info->dev, err,
                        ^
   In file included from drivers//scsi/xen-scsifront.c:50:0:
   include/xen/xenbus.h:224:6: note: expected 'struct xenbus_device *' but argument is of type 'struct xenbus_device **'
    void xenbus_dev_error(struct xenbus_device *dev, int err, const char *fmt, ...);
         ^~~~~~~~~~~~~~~~
   cc1: some warnings being treated as errors

vim +/xenbus_dev_error +663 drivers//scsi/xen-scsifront.c

   653	
   654	static int scsifront_sdev_configure(struct scsi_device *sdev)
   655	{
   656		struct vscsifrnt_info *info = shost_priv(sdev->host);
   657		int err;
   658	
   659		if (info && current == info->curr) {
   660			err = xenbus_printf(XBT_NIL, info->dev->nodename,
   661				      info->dev_state_path, "%d", XenbusStateConnected);
   662			if (err) {
 > 663				xenbus_dev_error(&info->dev, err,
   664					"%s: writing dev_state_path", __func__);
   665				return err;
   666			}
   667		}
   668	
   669		return 0;
   670	}
   671	

---
0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation
diff mbox

Patch

diff --git a/drivers/scsi/xen-scsifront.c b/drivers/scsi/xen-scsifront.c
index 36f59a1..be576cb 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;