ALSA: core: fix NULL checking in snd_pcm_plug_slave_size()

The dereference snd_pcm_plug_stream(plug) should come after the NULL
check snd_BUG_ON(!plug).

Signed-off-by: Xi Wang <xi.wang@gmail.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 2 insertions, 1 deletions

diff --git a/sound/core/oss/pcm_plugin.c b/sound/core/oss/pcm_plugin.c
index f0d7b1566a10..727ac44d39f4 100644
--- a/sound/core/oss/pcm_plugin.c
+++ b/sound/core/oss/pcm_plugin.c
@@ -231,13 +231,14 @@ snd_pcm_sframes_t snd_pcm_plug_slave_size(struct snd_pcm_substream *plug, snd_pc
 {
         struct snd_pcm_plugin *plugin, *plugin_prev, *plugin_next;
         snd_pcm_sframes_t frames;
-        int stream = snd_pcm_plug_stream(plug);
+        int stream;
         
         if (snd_BUG_ON(!plug))
                 return -ENXIO;
         if (clt_frames == 0)
                 return 0;
         frames = clt_frames;
+        stream = snd_pcm_plug_stream(plug);
         if (stream == SNDRV_PCM_STREAM_PLAYBACK) {
                 plugin = snd_pcm_plug_first(plug);
                 while (plugin && frames > 0) {