[PATCH 0/1] Fixed issues/defects reported by Coverity tool

[PATCH 0/1] Fixed issues/defects reported by Coverity tool

[sudarshan.bisht]

From: Sudarshan <sudarshan.bisht@nokia.com>

	Coverity Static Analysis helps developers find hard-to-spot,
yet potentially crash-causing defects early in the development phase,
reducing the cost,time, and risk of software errors.
	This patch has a fix for a situation where variable can become NULL 
after certain function call, but later not been checked before passing to 
the next function call. 

Sudarshan (1):
  alsa-lib: fixed coverity reported issues under "REVERSE_INULL"
    checker.

 src/control/setup.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

[PATCH 1/1] alsa-lib: fixed coverity reported issues under "REVERSE_INULL" checker.

[sudarshan.bisht]

From: Sudarshan <sudarshan.bisht@nokia.com>

---
 src/control/setup.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)

diff --git a/src/control/setup.c b/src/control/setup.c
index eecda45..79f2b76 100644
--- a/src/control/setup.c
+++ b/src/control/setup.c
@@ -398,7 +398,7 @@ static int snd_config_get_ctl_elem_value(snd_config_t *conf,
 
 static int add_elem(snd_sctl_t *h, snd_config_t *_conf, snd_config_t *private_data)
 {
-	snd_config_t *conf;
+	snd_config_t *conf = NULL ;
 	snd_config_iterator_t i, next;
 	char *tmp;
 	int iface = SND_CTL_ELEM_IFACE_MIXER;
@@ -415,6 +415,7 @@ static int add_elem(snd_sctl_t *h, snd_config_t *_conf, snd_config_t *private_da
 	err = snd_config_expand(_conf, _conf, NULL, private_data, &conf);
 	if (err < 0)
 		return err;
+	assert(conf);
 	snd_config_for_each(i, next, conf) {
 		snd_config_t *n = snd_config_iterator_entry(i);
 		const char *id;
-- 
1.7.0.4

Re: [PATCH 1/1] alsa-lib: fixed coverity reported issues under "REVERSE_INULL" checker.

[Clemens Ladisch]

sudarshan.bisht@nokia.com wrote:
> --- a/src/control/setup.c
> +++ b/src/control/setup.c
> @@ -398,7 +398,7 @@ static int snd_config_get_ctl_elem_value(snd_config_t *conf,
>  
>  static int add_elem(snd_sctl_t *h, snd_config_t *_conf, snd_config_t *private_data)
>  {
> -	snd_config_t *conf;
> +	snd_config_t *conf = NULL ;
>  	snd_config_iterator_t i, next;
>  	char *tmp;
>  	int iface = SND_CTL_ELEM_IFACE_MIXER;
> @@ -415,6 +415,7 @@ static int add_elem(snd_sctl_t *h, snd_config_t *_conf, snd_config_t *private_da
>  	err = snd_config_expand(_conf, _conf, NULL, private_data, &conf);
>  	if (err < 0)
>  		return err;
> +	assert(conf);
>  	snd_config_for_each(i, next, conf) {
>  		snd_config_t *n = snd_config_iterator_entry(i);
>  		const char *id;

The last parameter of snd_config_expand() is an output parameter, and
it is guaranteed that this parameter is set when the function succeeds.

If Coverity isn't able to derive this from the code, it might be
defensible to add annotations to snd_config_expand() to make the
semantics clear, but it is not acceptable to modify each caller just
to work around shortcomings in a tool.


Regards,
Clemens

Re: [PATCH 1/1] alsa-lib: fixed coverity reported issues under "REVERSE_INULL" checker.

[Sudarshan Bisht]

On Thu, 2011-03-17 at 12:29 +0100, ext Clemens Ladisch wrote:
> sudarshan.bisht@nokia.com wrote:
> > --- a/src/control/setup.c
> > +++ b/src/control/setup.c
> > @@ -398,7 +398,7 @@ static int snd_config_get_ctl_elem_value(snd_config_t *conf,
> >  
> >  static int add_elem(snd_sctl_t *h, snd_config_t *_conf, snd_config_t *private_data)
> >  {
> > -	snd_config_t *conf;
> > +	snd_config_t *conf = NULL ;
> >  	snd_config_iterator_t i, next;
> >  	char *tmp;
> >  	int iface = SND_CTL_ELEM_IFACE_MIXER;
> > @@ -415,6 +415,7 @@ static int add_elem(snd_sctl_t *h, snd_config_t *_conf, snd_config_t *private_da
> >  	err = snd_config_expand(_conf, _conf, NULL, private_data, &conf);
> >  	if (err < 0)
> >  		return err;
> > +	assert(conf);
> >  	snd_config_for_each(i, next, conf) {
> >  		snd_config_t *n = snd_config_iterator_entry(i);
> >  		const char *id;
> 
> The last parameter of snd_config_expand() is an output parameter, and
> it is guaranteed that this parameter is set when the function succeeds.
> 
> If Coverity isn't able to derive this from the code, it might be
> defensible to add annotations to snd_config_expand() to make the
> semantics clear, but it is not acceptable to modify each caller just
> to work around shortcomings in a tool.
Ok. 
> 
> 
> Regards,
> Clemens