[mythtv-users] mac build

[Mark Kendall]

On Tue, 2 Feb 2021 at 00:08, James Linder <jam at tigger.ws> wrote:
>
> Looks like a good start point, say if you want more:
>
> * thread #1, queue = 'com.apple.main-thread', stop reason = EXC_BAD_ACCESS (code=1, address=0x16c13e008)
>   * frame #0: 0x00000001044689a8 myth`AudioOutputGraph::GetImage(long long) const + 2008
> myth`AudioOutputGraph::GetImage:
> ->  0x1044689a8 <+2008>: movswl (%rax), %ecx
>     0x1044689ab <+2011>: movl   %ecx, -0x168(%rbp)
>     0x1044689b1 <+2017>: cmpl   $0x1, -0x154(%rbp)
>     0x1044689b8 <+2024>: jle    0x1044689d4               ; <+2052>
>
If I were a betting man, I'd guess that:-

https://github.com/MythTV/mythtv/blob/fixes/31/mythtv/libs/libmyth/audio/audiooutputgraph.cpp#L287

is the problem. e.g. the timestamps are bogus (due to the problematic
stream) and the error is not picked up and/or checked, we then convert
that timestamp to an offset into a buffer - and don't bounds check the
offset in:-

https://github.com/MythTV/mythtv/blob/fixes/31/mythtv/libs/libmyth/audio/audiooutputgraph.cpp#L123

However - I would expect the issue to be 100% repeatable if that were
the case...

James - when it doesn't crash - do you sometimes see garbage in the
audio graph or does it look 'normal'?

regards
Mark