nbd: check the return value of sysfs_create_file

[akpm@linux-foundation.org: fix it]
Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com>
Cc: Paul Clements <paul.clements@steeleye.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 11 insertions, 4 deletions

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 090796bef78..069ae39a9cd 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -366,20 +366,25 @@ static struct disk_attribute pid_attr = {
         .show = pid_show,
 };
 
-static void nbd_do_it(struct nbd_device *lo)
+static int nbd_do_it(struct nbd_device *lo)
 {
         struct request *req;
+        int ret;
 
         BUG_ON(lo->magic != LO_MAGIC);
 
         lo->pid = current->pid;
-        sysfs_create_file(&lo->disk->kobj, &pid_attr.attr);
+        ret = sysfs_create_file(&lo->disk->kobj, &pid_attr.attr);
+        if (ret) {
+                printk(KERN_ERR "nbd: sysfs_create_file failed!");
+                return ret;
+        }
 
         while ((req = nbd_read_stat(lo)) != NULL)
                 nbd_end_request(req);
 
         sysfs_remove_file(&lo->disk->kobj, &pid_attr.attr);
-        return;
+        return 0;
 }
 
 static void nbd_clear_que(struct nbd_device *lo)
@@ -569,7 +574,9 @@ static int nbd_ioctl(struct inode *inode, struct file *file,
         case NBD_DO_IT:
                 if (!lo->file)
                         return -EINVAL;
-                nbd_do_it(lo);
+                error = nbd_do_it(lo);
+                if (error)
+                        return error;
                 /* on return tidy up in case we have a signal */
                 /* Forcibly shutdown the socket causing all listeners
                  * to error