Description: media: firewire: firedtv-avc: fix a buffer overflow in avc_ca_pmt()
References:
 https://bugzilla.redhat.com/show_bug.cgi?id=1951739
 https://www.openwall.com/lists/oss-security/2021/04/20/1
 https://lore.kernel.org/linux-media/YHaulytonFcW+lyZ@mwanda/
 https://lore.kernel.org/linux-media/20210913152302.76d57784@coco.lan/
Notes:
Bugs:
upstream: needed
5.10-upstream-stable: needed
4.19-upstream-stable: needed
4.9-upstream-stable: needed
sid: needed
5.10-bullseye-security: needed
4.19-buster-security: needed
4.9-stretch-security: needed