[PATCH 3.16 163/254] ALSA: pcm: Add missing error checks in OSS emulation plugin builder

From: Ben Hutchings
Date: Wed Feb 28 2018 - 11:07:13 EST


3.16.55-rc1 review patch. If anyone has any objections, please let me know.

------------------

From: Takashi Iwai <tiwai@xxxxxxx>

commit 6708913750344a900f2e73bfe4a4d6dbbce4fe8d upstream.

In the OSS emulation plugin builder where the frame size is parsed in
the plugin chain, some places miss the possible errors returned from
the plugin src_ or dst_frames callback.

This patch papers over such places.

Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
sound/core/oss/pcm_plugin.c | 14 +++++++++++---
1 file changed, 11 insertions(+), 3 deletions(-)

--- a/sound/core/oss/pcm_plugin.c
+++ b/sound/core/oss/pcm_plugin.c
@@ -591,18 +591,26 @@ snd_pcm_sframes_t snd_pcm_plug_write_tra
snd_pcm_sframes_t frames = size;

plugin = snd_pcm_plug_first(plug);
- while (plugin && frames > 0) {
+ while (plugin) {
+ if (frames <= 0)
+ return frames;
if ((next = plugin->next) != NULL) {
snd_pcm_sframes_t frames1 = frames;
- if (plugin->dst_frames)
+ if (plugin->dst_frames) {
frames1 = plugin->dst_frames(plugin, frames);
+ if (frames1 <= 0)
+ return frames1;
+ }
if ((err = next->client_channels(next, frames1, &dst_channels)) < 0) {
return err;
}
if (err != frames1) {
frames = err;
- if (plugin->src_frames)
+ if (plugin->src_frames) {
frames = plugin->src_frames(plugin, frames1);
+ if (frames <= 0)
+ return frames;
+ }
}
} else
dst_channels = NULL;