L2CAP receive buffer overflow

L2CAP receive buffer overflow

[Некто Я]

Hello,

I am trying to send PC as wireless speaker with support for LDAC audio
codec. I used bluealsa with libldacdec fork (this one:
github.com/anonymix007/libldacdec) and it actually produced some sound
(but not for a long time), and it shows "Dropping L2CAP data: receive
buffer overflow" error in logs. Just as fork author, I modified kernel
(see issue: github.com/Arkq/bluez-alsa/issues/482) to check if it will
work and it indeed worked.


This is how it looks like now:


        if (chan->imtu < skb->len) {

            BT_ERR("Dropping L2CAP data: receive buffer overflow -
chan->imtu: %d, skb->len: %d", chan->imtu, skb->len);

            //goto drop;

        }

And the error it prints:

Dropping L2CAP data: receive buffer overflow - chan->imtu: 672, skb->len: 673


I'm on LMDE 4 with kernel 5.10 (now modified 5.10.46 version), Android
device I am using is OnePlus 7 Pro (Android 11, latest OS update)


I can suggest increasing buffer size a bit to fix this issue.