Fallout from commit 70fdb77 "audio/avrcp: Fix not always requesting capabilities"

Hello,

The commit 70fdb7 "audio/avrcp: Fix not always requesting capabilities"
introduced a series of bugs where the code thinks that session-

controller->player cannot be NULL, but in fact it can be so. The first

one was fixed in 177d27 "audio/avrcp: Fix crash when connecting to controllers", but there remain multiple code pathes via avrcp_register_notification() -> callback -> avrcp_handle_event() -> avrcp_{status,track,playback_pos,settings,uids}_changed() where session->controller->player may be dereferenced.

I'm unsure how to fix that properly (either not register notifications,
or ignore specific callbacks if s->c->player is NULL), so I'm just
reporting this.

Ref.: https://bugs.archlinux.org/task/48644

-- 
Ivan Shapovalov / intelfx /


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