[ALSA] ali5451 - Fix possible NULL dereference

Reported by Eric Sesterhenn.
Fix the wrong checks of extra voice pointer, which may cause NULL
dereferences.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

1 files changed, 3 insertions, 3 deletions

diff --git a/sound/pci/ali5451/ali5451.c b/sound/pci/ali5451/ali5451.c
index e1ed59549c50..cb59f994c68f 100644
--- a/sound/pci/ali5451/ali5451.c
+++ b/sound/pci/ali5451/ali5451.c
@@ -1250,7 +1250,7 @@ static int snd_ali_playback_hw_params(struct snd_pcm_substream *substream,
                         evoice->substream = substream;
                 }
         } else {
-                if (!evoice) {
+                if (evoice) {
                         snd_ali_free_voice(codec, evoice);
                         pvoice->extra = evoice = NULL;
                 }
@@ -1267,7 +1267,7 @@ static int snd_ali_playback_hw_free(struct snd_pcm_substream *substream)
         struct snd_ali_voice *evoice = pvoice ? pvoice->extra : NULL;
 
         snd_pcm_lib_free_pages(substream);
-        if (!evoice) {
+        if (evoice) {
                 snd_ali_free_voice(codec, evoice);
                 pvoice->extra = NULL;
         }
@@ -1356,7 +1356,7 @@ static int snd_ali_playback_prepare(struct snd_pcm_substream *substream)
                                  VOL,
                                  CTRL,
                                  EC);
-        if (!evoice) {
+        if (evoice) {
                 evoice->count = pvoice->count;
                 evoice->eso = pvoice->count << 1;
                 ESO = evoice->eso - 1;