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>

diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 090796bef78f16374f8c94f2bf70e23e602deabd..069ae39a9cd9023eb62d9115f2885383c2df86ef 100644 (file)
--- 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