Re: WARNING in port_delete

[Takashi Iwai]

On Tue, 24 Jul 2018 05:59:56 +0200,
DaeRyong Jeong wrote:
> 
> I just realized that the crash has been spotted by Syzkaller a few days 
> before.
> (https://syzkaller.appspot.com/bug?id=3490860a465e6b39227c6906f0ef2d40ad4d5bb1)
> 
> I'm CC'ing Syzkaller's mailing list.

It's very likely a false-positive sanity check, and if so, nothing
serious at all.  We may simply remove two snd_BUG_ON() lines.

But I'd love to have a C reproducer to confirm my understanding is
correct...


thanks,

Takashi

---
--- a/sound/core/seq/seq_ports.c
+++ b/sound/core/seq/seq_ports.c
@@ -272,9 +272,6 @@ static int port_delete(struct snd_seq_client *client,
        if (port->private_free)
                port->private_free(port->private_data);
 
-       snd_BUG_ON(port->c_src.count != 0);
-       snd_BUG_ON(port->c_dest.count != 0);
-
        kfree(port);
        return 0;
 }