[PATCH] staging: gpib: cb7210: Add error handling

[PATCH] staging: gpib: cb7210: Add error handling

[Nihar Chaithanya]

The if condition in cb7210_init_module() would always fail as
the value of err is constantly 0.
Add error handling to cb_pcmcia_init_module() where it returns
appropriate error code if pcmcia_register_driver() fails.

This issue was reported by Coverity Scan.
Report:

CID 1635894: (#1 of 1): 'Constant' variable guards dead code (DEADCODE)
dead_error_line: Execution cannot reach this statement: return -1;.

Signed-off-by: Nihar Chaithanya <niharchaithanya@gmail.com>
---
 drivers/staging/gpib/cb7210/cb7210.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/gpib/cb7210/cb7210.c b/drivers/staging/gpib/cb7210/cb7210.c
index 63df7f3eb3f3..b2f6ad70ccaf 100644
--- a/drivers/staging/gpib/cb7210/cb7210.c
+++ b/drivers/staging/gpib/cb7210/cb7210.c
@@ -1353,7 +1353,11 @@ static struct pcmcia_driver cb_gpib_cs_driver = {
 
 int cb_pcmcia_init_module(void)
 {
-	pcmcia_register_driver(&cb_gpib_cs_driver);
+	int ret;
+
+	ret = pcmcia_register_driver(&cb_gpib_cs_driver);
+	if (ret < 0)
+		return ret;
 	return 0;
 }
 
@@ -1528,9 +1532,10 @@ static int __init cb7210_init_module(void)
 	gpib_register_driver(&cb_pcmcia_unaccel_interface, THIS_MODULE);
 	err += cb_pcmcia_init_module();
 #endif
-	if (err)
+	if (err) {
+		pr_err("cb7210: registering PCMCIA driver with the bus core failed\n");
 		return -1;
-
+	}
 	return 0;
 }
 
-- 
2.34.1

Re: [PATCH] staging: gpib: cb7210: Add error handling

[Greg KH]

On Sat, Dec 21, 2024 at 07:56:33AM +0530, Nihar Chaithanya wrote:
> The if condition in cb7210_init_module() would always fail as
> the value of err is constantly 0.
> Add error handling to cb_pcmcia_init_module() where it returns
> appropriate error code if pcmcia_register_driver() fails.
> 
> This issue was reported by Coverity Scan.
> Report:
> 
> CID 1635894: (#1 of 1): 'Constant' variable guards dead code (DEADCODE)
> dead_error_line: Execution cannot reach this statement: return -1;.
> 
> Signed-off-by: Nihar Chaithanya <niharchaithanya@gmail.com>
> ---
>  drivers/staging/gpib/cb7210/cb7210.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/staging/gpib/cb7210/cb7210.c b/drivers/staging/gpib/cb7210/cb7210.c
> index 63df7f3eb3f3..b2f6ad70ccaf 100644
> --- a/drivers/staging/gpib/cb7210/cb7210.c
> +++ b/drivers/staging/gpib/cb7210/cb7210.c
> @@ -1353,7 +1353,11 @@ static struct pcmcia_driver cb_gpib_cs_driver = {
>  
>  int cb_pcmcia_init_module(void)
>  {
> -	pcmcia_register_driver(&cb_gpib_cs_driver);
> +	int ret;
> +
> +	ret = pcmcia_register_driver(&cb_gpib_cs_driver);
> +	if (ret < 0)
> +		return ret;
>  	return 0;

Why not make this whole function just one line?  And then, as it's one
line, why is it a function at all?

thanks,

greg k-h

Re: [PATCH] staging: gpib: cb7210: Add error handling

[Nihar Chaithanya]

On 21/12/24 13:21, Greg KH wrote:
> On Sat, Dec 21, 2024 at 07:56:33AM +0530, Nihar Chaithanya wrote:
>> The if condition in cb7210_init_module() would always fail as
>> the value of err is constantly 0.
>> Add error handling to cb_pcmcia_init_module() where it returns
>> appropriate error code if pcmcia_register_driver() fails.
>>
>> This issue was reported by Coverity Scan.
>> Report:
>>
>> CID 1635894: (#1 of 1): 'Constant' variable guards dead code (DEADCODE)
>> dead_error_line: Execution cannot reach this statement: return -1;.
>>
>> Signed-off-by: Nihar Chaithanya <niharchaithanya@gmail.com>
>> ---
>>   drivers/staging/gpib/cb7210/cb7210.c | 11 ++++++++---
>>   1 file changed, 8 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/staging/gpib/cb7210/cb7210.c b/drivers/staging/gpib/cb7210/cb7210.c
>> index 63df7f3eb3f3..b2f6ad70ccaf 100644
>> --- a/drivers/staging/gpib/cb7210/cb7210.c
>> +++ b/drivers/staging/gpib/cb7210/cb7210.c
>> @@ -1353,7 +1353,11 @@ static struct pcmcia_driver cb_gpib_cs_driver = {
>>   
>>   int cb_pcmcia_init_module(void)
>>   {
>> -	pcmcia_register_driver(&cb_gpib_cs_driver);
>> +	int ret;
>> +
>> +	ret = pcmcia_register_driver(&cb_gpib_cs_driver);
>> +	if (ret < 0)
>> +		return ret;
>>   	return 0;
> Why not make this whole function just one line?  And then, as it's one
> line, why is it a function at all?
>
> thanks,
>
> greg k-h
Hi Greg, yes, this redundant cb_pcmcia_init_module() can be replaced with
pcmcia_register_driver() where it's being called. I'll send the version 2
making these changes.

Thank you,
Nihar