On Fri, Oct 08, 2021 at 01:15:58AM +0100, Colin King wrote:
> From: Colin Ian King <[email protected]>
>
> There is an error return path where the error return is being
> assigned to err rather than count and the error exit path does
> not return -EAGAIN as expected. Fix this by setting the error
> return to variable count as this is the value that is returned
> at the end of the function.
>
> Addresses-Coverity: ("Unused value")
> Fixes: 00c4da27a421 ("carl9170: firmware parser and debugfs code")
> Signed-off-by: Colin Ian King <[email protected]>
> ---
> drivers/net/wireless/ath/carl9170/debug.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/net/wireless/ath/carl9170/debug.c b/drivers/net/wireless/ath/carl9170/debug.c
> index bb40889d7c72..f163c6bdac8f 100644
> --- a/drivers/net/wireless/ath/carl9170/debug.c
> +++ b/drivers/net/wireless/ath/carl9170/debug.c
> @@ -628,7 +628,7 @@ static ssize_t carl9170_debugfs_bug_write(struct ar9170 *ar, const char *buf,
>
> case 'R':
> if (!IS_STARTED(ar)) {
> - err = -EAGAIN;
> + count = -EAGAIN;
> goto out;
This is ugly. The bug wouldn't have happened with a direct return, it's
only the goto out which causes it. Better to replace all the error
paths with direct returns. There are two other direct returns so it's
not like a new thing...
Goto out on the success path is fine here, though.
regards,
dan carpenter
On 08/10/2021 06:58, Dan Carpenter wrote:
> On Fri, Oct 08, 2021 at 01:15:58AM +0100, Colin King wrote:
>> From: Colin Ian King <[email protected]>
>>
>> There is an error return path where the error return is being
>> assigned to err rather than count and the error exit path does
>> not return -EAGAIN as expected. Fix this by setting the error
>> return to variable count as this is the value that is returned
>> at the end of the function.
>>
>> Addresses-Coverity: ("Unused value")
>> Fixes: 00c4da27a421 ("carl9170: firmware parser and debugfs code")
>> Signed-off-by: Colin Ian King <[email protected]>
>> ---
>> drivers/net/wireless/ath/carl9170/debug.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/net/wireless/ath/carl9170/debug.c b/drivers/net/wireless/ath/carl9170/debug.c
>> index bb40889d7c72..f163c6bdac8f 100644
>> --- a/drivers/net/wireless/ath/carl9170/debug.c
>> +++ b/drivers/net/wireless/ath/carl9170/debug.c
>> @@ -628,7 +628,7 @@ static ssize_t carl9170_debugfs_bug_write(struct ar9170 *ar, const char *buf,
>>
>> case 'R':
>> if (!IS_STARTED(ar)) {
>> - err = -EAGAIN;
>> + count = -EAGAIN;
>> goto out;
>
> This is ugly. The bug wouldn't have happened with a direct return, it's
> only the goto out which causes it. Better to replace all the error
> paths with direct returns. There are two other direct returns so it's
> not like a new thing...
Yep, I agree it was ugly, I was trying to keep to the coding style and
reduce the patch delta size. I can do a V2 if the maintainers deem it's
a cleaner solution.
>
> Goto out on the success path is fine here, though.
Yep. I believe that a goto to one exit return point (may possibly?) make
the code smaller rather than a sprinkling of returns in a function, so
I'm never sure if this is a win or not with these kind of cases.
Colin
>
> regards,
> dan carpenter
>
Hello,
On 08/10/2021 09:31, Colin Ian King wrote:
> On 08/10/2021 06:58, Dan Carpenter wrote:
>> On Fri, Oct 08, 2021 at 01:15:58AM +0100, Colin King wrote:
>>> From: Colin Ian King <[email protected]>
>>>
>>> There is an error return path where the error return is being
>>> assigned to err rather than count and the error exit path does
>>> not return -EAGAIN as expected. Fix this by setting the error
>>> return to variable count as this is the value that is returned
>>> at the end of the function.
>>>
>>> Addresses-Coverity: ("Unused value")
>>> Fixes: 00c4da27a421 ("carl9170: firmware parser and debugfs code")
>>> Signed-off-by: Colin Ian King <[email protected]>
>>> ---
>>> drivers/net/wireless/ath/carl9170/debug.c | 2 +-
>>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/net/wireless/ath/carl9170/debug.c b/drivers/net/wireless/ath/carl9170/debug.c
>>> index bb40889d7c72..f163c6bdac8f 100644
>>> --- a/drivers/net/wireless/ath/carl9170/debug.c
>>> +++ b/drivers/net/wireless/ath/carl9170/debug.c
>>> @@ -628,7 +628,7 @@ static ssize_t carl9170_debugfs_bug_write(struct ar9170 *ar, const char *buf,
>>> case 'R':
>>> if (!IS_STARTED(ar)) {
>>> - err = -EAGAIN;
>>> + count = -EAGAIN;
>>> goto out;
>>
>> This is ugly. The bug wouldn't have happened with a direct return, it's
>> only the goto out which causes it. Better to replace all the error
>> paths with direct returns. There are two other direct returns so it's
>> not like a new thing...
>
> Yep, I agree it was ugly, I was trying to keep to the coding style and reduce the patch delta size. I can do a V2 if the maintainers deem it's a cleaner solution.
Hm? I don't think there's any need to stick to a particular
coding style. This file hasn't been touched a lot since 2010.
Things moved on and replacing the gotos with straight return
is totally fine.
(It has to pass the build checkers of course. However I don't
think this will be a problem here...)
Cheers,
Christian