copy_to_user() returns the number of remaining bytes. Avoid that a larger value is returned than the number of bytes that have been copied by returning -EFAULT if not all bytes have been copied. Signed-off-by: Bart Van Assche <bart.vanassche@xxxxxxx> --- drivers/md/bcache/debug.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/drivers/md/bcache/debug.c b/drivers/md/bcache/debug.c index af89408befe8..376899cfcbf1 100644 --- a/drivers/md/bcache/debug.c +++ b/drivers/md/bcache/debug.c @@ -175,9 +175,8 @@ static ssize_t bch_dump_read(struct file *file, char __user *buf, struct keybuf_key *w; unsigned 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; -- 2.16.2
