[PATCH 3.18 39/93] ALSA: pcm: potential uninitialized return values

From: Greg Kroah-Hartman
Date: Fri Apr 06 2018 - 09:26:37 EST


3.18-stable review patch. If anyone has any objections, please let me know.

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

From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

commit 5607dddbfca774fb38bffadcb077fe03aa4ac5c6 upstream.

Smatch complains that "tmp" can be uninitialized if we do a zero size
write.

Fixes: 02a5d6925cd3 ("ALSA: pcm: Avoid potential races between OSS ioctls and read/write")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Takashi Iwai <tiwai@xxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
sound/core/oss/pcm_oss.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

--- a/sound/core/oss/pcm_oss.c
+++ b/sound/core/oss/pcm_oss.c
@@ -1362,7 +1362,7 @@ static ssize_t snd_pcm_oss_write2(struct
static ssize_t snd_pcm_oss_write1(struct snd_pcm_substream *substream, const char __user *buf, size_t bytes)
{
size_t xfer = 0;
- ssize_t tmp;
+ ssize_t tmp = 0;
struct snd_pcm_runtime *runtime = substream->runtime;

if (atomic_read(&substream->mmap_count))
@@ -1469,7 +1469,7 @@ static ssize_t snd_pcm_oss_read2(struct
static ssize_t snd_pcm_oss_read1(struct snd_pcm_substream *substream, char __user *buf, size_t bytes)
{
size_t xfer = 0;
- ssize_t tmp;
+ ssize_t tmp = 0;
struct snd_pcm_runtime *runtime = substream->runtime;

if (atomic_read(&substream->mmap_count))