alsa-project/alsa-lib issue #314 was edited from npitre:

The espeak program is crashing randomly here. I've been able to isolate the issue in a small test program demonstrating the crash 100% of the time, ending in:

``` alsa_quickcrash: pcm.c:3236: snd_pcm_area_copy: Assertion `src < dst || src >= dst + bytes' failed. Aborted (core dumped) ```

Here's the test code:

``` /* to compile: gcc -O2 -Wall -o alsa_quickcrash alsa_quickcrash.c -lasound */

#include <alsa/asoundlib.h> #include <stdio.h> #include <string.h>

#define DEVICE "test_dummy" #define RATE 22050 #define CHANNELS 1 #define FORMAT SND_PCM_FORMAT_S16_LE #define BUF_MS 60

#define DO(x) if (x < 0) { fprintf(stderr, "%s failed\n", #x); exit(1); }

int main() { unsigned int rate = RATE; snd_pcm_uframes_t frames = RATE * BUF_MS / 1000; snd_pcm_t *handle; snd_pcm_hw_params_t *params;

DO(snd_pcm_hw_params_malloc(&params)); DO(snd_pcm_open(&handle, DEVICE, SND_PCM_STREAM_PLAYBACK, 0)); DO(snd_pcm_hw_params_any(handle, params)); DO(snd_pcm_hw_params_set_access(handle, params, SND_PCM_ACCESS_RW_INTERLEAVED)); DO(snd_pcm_hw_params_set_format(handle, params, FORMAT)); DO(snd_pcm_hw_params_set_rate_near(handle, params, &rate, 0)); DO(snd_pcm_hw_params_set_channels(handle, params, CHANNELS)); DO(snd_pcm_hw_params_set_buffer_size_near(handle, params, &frames)); DO(snd_pcm_hw_params(handle, params)); DO(snd_pcm_prepare(handle));

printf("PCM config dump:\n"); snd_output_t *output = NULL; DO(snd_output_stdio_attach(&output, stdout, 0)); DO(snd_pcm_dump(handle, output)); printf("\n");

printf("frames = %ld\n", (long)frames); short data[frames * CHANNELS]; memset(data, 0, sizeof(data));

printf("writing whole buffer\n"); DO(snd_pcm_writei(handle, data, frames)); printf("writing whole buffer\n"); DO(snd_pcm_writei(handle, data, frames)); printf("writing whole buffer minus 1 frame\n"); DO(snd_pcm_writei(handle, data, frames - 1));

printf("draining audio\n"); DO(snd_pcm_drain(handle)); printf("done\n"); DO(snd_pcm_close(handle)); return 0; } ```

Here's the corresponding .asoundrc content:

``` pcm.test_dummy { type plug slave.pcm "mix_dummy" }

pcm.mix_dummy { type dmix ipc_key 1024 ipc_key_add_uid false ipc_perm 0666 slave { pcm "hw:0" period_size 1024 buffer_size 4096 format "S16_LE" rate 48000 } } ```

And here's the complete test output:

``` PCM config dump: Plug PCM: Rate conversion PCM (48000, sformat=S16_LE) Converter: linear-interpolation Protocol version: 10003 Its setup is: stream : PLAYBACK access : RW_INTERLEAVED format : S16_LE subformat : STD channels : 1 rate : 22050 exact rate : 22050 (22050/1) msbits : 16 buffer_size : 1411 period_size : 470 period_time : 21333 tstamp_mode : NONE tstamp_type : MONOTONIC period_step : 1 avail_min : 470 period_event : 0 start_threshold : 1 stop_threshold : 1411 silence_threshold: 0 silence_size : 0 boundary : 3177289537109884928 Slave: Route conversion PCM (sformat=S16_LE) Transformation table: 0 <- 0 1 <- 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 1 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 3072 period_size : 1024 period_time : 21333 tstamp_mode : NONE tstamp_type : MONOTONIC period_step : 1 avail_min : 1024 period_event : 0 start_threshold : 2 stop_threshold : 3072 silence_threshold: 0 silence_size : 0 boundary : 6917529027641081856 Slave: Direct Stream Mixing PCM Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 3072 period_size : 1024 period_time : 21333 tstamp_mode : NONE tstamp_type : MONOTONIC period_step : 1 avail_min : 1024 period_event : 0 start_threshold : 2 stop_threshold : 3072 silence_threshold: 0 silence_size : 0 boundary : 6917529027641081856 Hardware PCM card 1 'HDA Intel PCH' device 0 subdevice 0 Its setup is: stream : PLAYBACK access : MMAP_INTERLEAVED format : S16_LE subformat : STD channels : 2 rate : 48000 exact rate : 48000 (48000/1) msbits : 16 buffer_size : 4096 period_size : 1024 period_time : 21333 tstamp_mode : ENABLE tstamp_type : MONOTONIC period_step : 1 avail_min : 1024 period_event : 0 start_threshold : 1 stop_threshold : 0 silence_threshold: 0 silence_size : 0 boundary : 4611686018427387904 appl_ptr : 0 hw_ptr : 2734916609

frames = 1411 writing whole buffer writing whole buffer writing whole buffer minus 1 frame draining audio alsa_quickcrash: pcm.c:3236: snd_pcm_area_copy: Assertion `src < dst || src >= dst + bytes' failed. Aborted (core dumped) ```

Issue URL : https://github.com/alsa-project/alsa-lib/issues/314 Repository URL: https://github.com/alsa-project/alsa-lib