Data is written for each channel but is only tracked as having one channel written. This resulted in a buffer overflow and corruption of the allocator's metadata which caused further problems when the buffer was later freed. This could be observed with sandbox unit tests.
Resolve the overflow by tracking the writes for each channel.
Fixes: f987177db9 ("dm: sound: Use the correct number of channels for sound") Signed-off-by: Andrew Scull ascull@google.com Cc: Simon Glass sjg@chromium.org --- drivers/sound/sound.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-)
diff --git a/drivers/sound/sound.c b/drivers/sound/sound.c index b0eab23391..041dfdccfe 100644 --- a/drivers/sound/sound.c +++ b/drivers/sound/sound.c @@ -25,13 +25,11 @@ void sound_create_square_wave(uint sample_rate, unsigned short *data, int size, int i, j;
for (i = 0; size && i < half; i++) { - size -= 2; - for (j = 0; j < channels; j++) + for (j = 0; size && j < channels; j++, size -= 2) *data++ = amplitude; } for (i = 0; size && i < period - half; i++) { - size -= 2; - for (j = 0; j < channels; j++) + for (j = 0; size && j < channels; j++, size -= 2) *data++ = -amplitude; } }