bcache: Fix an error code in bch_dump_read()

The copy_to_user() function returns the number of bytes remaining to be
copied, but the intention here was to return -EFAULT if the copy fails.

Fixes: cafe56359144 ("bcache: A block layer cache")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Coly Li <colyli@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c
index 8b123be05254d39bcc4ca33caa6af01bf5056cfb..336f439103831b624468ea18a6b1ecf645312fdb 100644 (file)
--- a/drivers/md/bcache/debug.c
+++ b/drivers/md/bcache/debug.c
@@ -178,10 +178,9 @@ static ssize_t bch_dump_read(struct file *file, char __user *buf,
        while (size) {
                struct keybuf_key *w;
                unsigned int bytes = min(i->bytes, size);
-               int err = copy_to_user(buf, i->buf, bytes);
 
-               if (err)
-                       return err;
+               if (copy_to_user(buf, i->buf, bytes))
+                       return -EFAULT;
 
                ret      += bytes;
                buf      += bytes;