If we write zero bytes to this debugfs file, then it will cause an underflow when we do copy_from_user(buf, ubuf, count - 1). Debugfs can normally only be written to by root so the impact of this is low.
Signed-off-by: Dan Carpenter <[email protected]> diff --git a/fs/orangefs/orangefs-debugfs.c b/fs/orangefs/orangefs-debugfs.c index 791912da97d7..716ed337f166 100644 --- a/fs/orangefs/orangefs-debugfs.c +++ b/fs/orangefs/orangefs-debugfs.c @@ -440,6 +440,9 @@ static ssize_t orangefs_debug_write(struct file *file, "orangefs_debug_write: %pD\n", file); + if (count == 0) + return 0; + /* * Thwart users who try to jamb a ridiculous number * of bytes into the debug file...
