[PATCH AUTOSEL for 4.9 149/156] scsi: sd: change allow_restart to bool in sysfs interface

[alexander . levin]

From: weiping zhang <zhangweip...@didichuxing.com>

[ Upstream commit 658e9a6dc1126f21fa417cd213e1cdbff8be0ba2 ]

/sys/class/scsi_disk/0:2:0:0/allow_restart can be changed to 0
unexpectedly by writing an invalid string such as the following:

echo asdf > /sys/class/scsi_disk/0:2:0:0/allow_restart

Signed-off-by: weiping zhang <zhangweip...@didichuxing.com>
Signed-off-by: Martin K. Petersen <martin.peter...@oracle.com>
Signed-off-by: Sasha Levin <alexander.le...@verizon.com>
---
 drivers/scsi/sd.c | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 66e1c2ea79d7..ace56c5e61e1 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -260,6 +260,7 @@ static ssize_t
 allow_restart_store(struct device *dev, struct device_attribute *attr,
                    const char *buf, size_t count)
 {
+       bool v;
        struct scsi_disk *sdkp = to_scsi_disk(dev);
        struct scsi_device *sdp = sdkp->device;
 
@@ -269,7 +270,10 @@ allow_restart_store(struct device *dev, struct 
device_attribute *attr,
        if (sdp->type != TYPE_DISK)
                return -EINVAL;
 
-       sdp->allow_restart = simple_strtoul(buf, NULL, 10);
+       if (kstrtobool(buf, &v))
+               return -EINVAL;
+
+       sdp->allow_restart = v;
 
        return count;
 }
-- 
2.11.0