'realloc(): invalid old size' seemingly thrown at random

[KaySteinhoff]

I've implemented a simple .wav loading function in my program and it works somewhat.

I can configure and start the playback without issue however at some random time, and I do mean random, a 'realloc(): invalid old size' error occurs and terminates the playback. Timing is completely irrelevant since I've had my test file playing for 5 minutes on loop before crashing, having it terminate immediately as well as anything inbetween.

The debug output seems fine though:

DEBUG: WASAPI backend is disabled.
DEBUG: DirectSound backend is disabled.
DEBUG: WinMM backend is disabled.
DEBUG: Core Audio backend is disabled.
DEBUG: sndio backend is disabled.
DEBUG: audio(4) backend is disabled.
DEBUG: OSS backend is disabled.
DEBUG: Attempting to initialize PulseAudio backend...
DEBUG: Loading library: libpulse.so
DEBUG: Loading symbol: pa_mainloop_new
DEBUG: Loading symbol: pa_mainloop_free
DEBUG: Loading symbol: pa_mainloop_quit
DEBUG: Loading symbol: pa_mainloop_get_api
DEBUG: Loading symbol: pa_mainloop_iterate
DEBUG: Loading symbol: pa_mainloop_wakeup
DEBUG: Loading symbol: pa_threaded_mainloop_new
DEBUG: Loading symbol: pa_threaded_mainloop_free
DEBUG: Loading symbol: pa_threaded_mainloop_start
DEBUG: Loading symbol: pa_threaded_mainloop_stop
DEBUG: Loading symbol: pa_threaded_mainloop_lock
DEBUG: Loading symbol: pa_threaded_mainloop_unlock
DEBUG: Loading symbol: pa_threaded_mainloop_wait
DEBUG: Loading symbol: pa_threaded_mainloop_signal
DEBUG: Loading symbol: pa_threaded_mainloop_accept
DEBUG: Loading symbol: pa_threaded_mainloop_get_retval
DEBUG: Loading symbol: pa_threaded_mainloop_get_api
DEBUG: Loading symbol: pa_threaded_mainloop_in_thread
DEBUG: Loading symbol: pa_threaded_mainloop_set_name
DEBUG: Loading symbol: pa_context_new
DEBUG: Loading symbol: pa_context_unref
DEBUG: Loading symbol: pa_context_connect
DEBUG: Loading symbol: pa_context_disconnect
DEBUG: Loading symbol: pa_context_set_state_callback
DEBUG: Loading symbol: pa_context_get_state
DEBUG: Loading symbol: pa_context_get_sink_info_list
DEBUG: Loading symbol: pa_context_get_source_info_list
DEBUG: Loading symbol: pa_context_get_sink_info_by_name
DEBUG: Loading symbol: pa_context_get_source_info_by_name
DEBUG: Loading symbol: pa_operation_unref
DEBUG: Loading symbol: pa_operation_get_state
DEBUG: Loading symbol: pa_channel_map_init_extend
DEBUG: Loading symbol: pa_channel_map_valid
DEBUG: Loading symbol: pa_channel_map_compatible
DEBUG: Loading symbol: pa_stream_new
DEBUG: Loading symbol: pa_stream_unref
DEBUG: Loading symbol: pa_stream_connect_playback
DEBUG: Loading symbol: pa_stream_connect_record
DEBUG: Loading symbol: pa_stream_disconnect
DEBUG: Loading symbol: pa_stream_get_state
DEBUG: Loading symbol: pa_stream_get_sample_spec
DEBUG: Loading symbol: pa_stream_get_channel_map
DEBUG: Loading symbol: pa_stream_get_buffer_attr
DEBUG: Loading symbol: pa_stream_set_buffer_attr
DEBUG: Loading symbol: pa_stream_get_device_name
DEBUG: Loading symbol: pa_stream_set_write_callback
DEBUG: Loading symbol: pa_stream_set_read_callback
DEBUG: Loading symbol: pa_stream_set_suspended_callback
DEBUG: Loading symbol: pa_stream_set_moved_callback
DEBUG: Loading symbol: pa_stream_is_suspended
DEBUG: Loading symbol: pa_stream_flush
DEBUG: Loading symbol: pa_stream_drain
DEBUG: Loading symbol: pa_stream_is_corked
DEBUG: Loading symbol: pa_stream_cork
DEBUG: Loading symbol: pa_stream_trigger
DEBUG: Loading symbol: pa_stream_begin_write
DEBUG: Loading symbol: pa_stream_write
DEBUG: Loading symbol: pa_stream_peek
DEBUG: Loading symbol: pa_stream_drop
DEBUG: Loading symbol: pa_stream_writable_size
DEBUG: Loading symbol: pa_stream_readable_size
DEBUG: System Architecture:
DEBUG:   Endian: LE
DEBUG:   SSE2:   YES
DEBUG:   AVX2:   NO
DEBUG:   NEON:   NO
INFO: [PulseAudio] Playback attr: maxlength=6612, tlength=2204, prebuf=-1, minreq=-1, fragsize=2204; periodSizeInFrames=551
INFO: [PulseAudio] Playback sample spec: format=16-bit Signed Integer, channels=2, rate=22050
INFO: [PulseAudio] Playback actual attr: maxlength=6612, tlength=1652, prebuf=1108, minreq=548, fragsize=2204; internalPeriodSizeInFrames=413
INFO: [PulseAudio]
INFO:   Corsair VOID ELITE USB Gaming Headset Analog Stereo (Playback)
INFO:     Format:      16-bit Signed Integer -> 16-bit Signed Integer
INFO:     Channels:    2 -> 2
INFO:     Sample Rate: 22050 -> 22050
INFO:     Buffer Size: 413*4 (1652)
INFO:     Conversion:
INFO:       Pre Format Conversion:  NO
INFO:       Post Format Conversion: NO
INFO:       Channel Routing:        NO
INFO:       Resampling:             NO
INFO:       Passthrough:            YES
INFO:       Channel Map In:         {CHANNEL_FRONT_LEFT CHANNEL_FRONT_RIGHT}
INFO:       Channel Map Out:        {CHANNEL_FRONT_LEFT CHANNEL_FRONT_RIGHT}
realloc(): invalid old size
Aborted (core dumped)

Neither timing nor playback file play a role in it failing after some unspecified time.

[mackron]

Not entirely sure what's going on here. Do you have a call stack or anything to narrow it down? Seems a bit strange - I can't think of anything off the top of my head in miniaudio that would be doing allocations after the device has been initialized.

[KaySteinhoff]

@mackron Unfortunately I don't have a call stack since it's all mangled. However after a bit of searching I've found two possible culprits: "ma_stbvorbis_init_internal_decoder_push" and "ma_stbvorbis_read_pcm_frames". Although in both instances ma_realloc is called before pVorbis->onRead I suspect "ma_stbvorbis_read_pcm_frames" is actually causing the crash since it seems to at least initialize.

I've not read enough of the source code to make a definitive answer though. I'll try to get a usable call stack as it shouldn't be too difficult to implement in my project since I've started implementing it a while ago anyways I'll just have to resolve the function names using dl or something.

[mackron]

Regardless of the cause of the crash, you should transition away from the stb_vorbis stuff. That's being removed in a future version of miniaudio (not sure the exact version yet). The recommended way to support Vorbis is via libvorbis and the custom decoder in the extras folder.

Since this is happening in the decoder, one thing to check is that everything is thread safe. ma_decoder is not thread safe, so you need to make sure you do your own syncing. A common error is reading from the audio callback, and then seeking from another thread - that's erroneous usage.