Commit 4285de07 authored by Takashi Iwai's avatar Takashi Iwai
Browse files

ALSA: pcm: oss: Place the plugin buffer overflow checks correctly 

The checks of the plugin buffer overflow in the previous fix by commit
  f2ecf903 ("ALSA: pcm: oss: Avoid plugin buffer overflow")
are put in the wrong places mistakenly, which leads to the expected
(repeated) sound when the rate plugin is involved.  Fix in the right
places.

Also, at those right places, the zero check is needed for the
termination node, so added there as well, and let's get it done,
finally.

Fixes: f2ecf903 ("ALSA: pcm: oss: Avoid plugin buffer overflow")
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200424193350.19678-1-tiwai@suse.de


Signed-off-by: default avatarTakashi Iwai <tiwai@suse.de>
parent ae769d35

sound/core/oss/pcm_plugin.c

+12 −8
Original line number Diff line number Diff line
@@ -211,21 +211,23 @@ static snd_pcm_sframes_t plug_client_size(struct snd_pcm_substream *plug, 
	if (stream == SNDRV_PCM_STREAM_PLAYBACK) {

		plugin = snd_pcm_plug_last(plug);

		while (plugin && drv_frames > 0) {

			if (check_size && drv_frames > plugin->buf_frames)

				drv_frames = plugin->buf_frames;

			plugin_prev = plugin->prev;

			if (plugin->src_frames)

				drv_frames = plugin->src_frames(plugin, drv_frames);

			if (check_size && plugin->buf_frames &&

			    drv_frames > plugin->buf_frames)

				drv_frames = plugin->buf_frames;

			plugin = plugin_prev;

		}

	} else if (stream == SNDRV_PCM_STREAM_CAPTURE) {

		plugin = snd_pcm_plug_first(plug);

		while (plugin && drv_frames > 0) {

			plugin_next = plugin->next;

			if (check_size && plugin->buf_frames &&

			    drv_frames > plugin->buf_frames)

				drv_frames = plugin->buf_frames;

			if (plugin->dst_frames)

				drv_frames = plugin->dst_frames(plugin, drv_frames);

			if (check_size && drv_frames > plugin->buf_frames)

				drv_frames = plugin->buf_frames;

			plugin = plugin_next;

		}

	} else
@@ -251,26 +253,28 @@ static snd_pcm_sframes_t plug_slave_size(struct snd_pcm_substream *plug, 
		plugin = snd_pcm_plug_first(plug);

		while (plugin && frames > 0) {

			plugin_next = plugin->next;

			if (check_size && plugin->buf_frames &&

			    frames > plugin->buf_frames)

				frames = plugin->buf_frames;

			if (plugin->dst_frames) {

				frames = plugin->dst_frames(plugin, frames);

				if (frames < 0)

					return frames;

			}

			if (check_size && frames > plugin->buf_frames)

				frames = plugin->buf_frames;

			plugin = plugin_next;

		}

	} else if (stream == SNDRV_PCM_STREAM_CAPTURE) {

		plugin = snd_pcm_plug_last(plug);

		while (plugin) {

			if (check_size && frames > plugin->buf_frames)

				frames = plugin->buf_frames;

			plugin_prev = plugin->prev;

			if (plugin->src_frames) {

				frames = plugin->src_frames(plugin, frames);

				if (frames < 0)

					return frames;

			}

			if (check_size && plugin->buf_frames &&

			    frames > plugin->buf_frames)

				frames = plugin->buf_frames;

			plugin = plugin_prev;

		}

	} else

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