Subject: Re: [PATCH] crypto: cleanup warning in qm_get_qos_value()
To:     Nathan Chancellor <nathan@kernel.org>
Cc:     wangzhou1@hisilicon.com, herbert@gondor.apana.org.au,
        davem@davemloft.net, ndesaulniers@google.com,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        llvm@lists.linux.dev
References: <20211221205953.3128923-1-trix@redhat.com>
 <YcJHoqXXVFZatIla@archlinux-ax161>
From:   Tom Rix <trix@redhat.com>
Message-ID: <73952545-2236-6065-3016-543e8d503c06@redhat.com>
Date:   Wed, 22 Dec 2021 06:46:51 -0800
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On 12/21/21 1:31 PM, Nathan Chancellor wrote:
> On Tue, Dec 21, 2021 at 12:59:53PM -0800, trix@redhat.com wrote:
>> From: Tom Rix <trix@redhat.com>
>>
>> Building with clang static analysis returns this warning:
>>
>> qm.c:4382:11: warning: The left operand of '==' is a garbage value
>>          if (*val == 0 || *val > QM_QOS_MAX_VAL || ret) {
>>              ~~~~ ^
>>
>> The call to qm_qos_value_init() can return an error without setting
>> *val.  So check ret before checking *val.
>>
>> Signed-off-by: Tom Rix <trix@redhat.com>
> Reviewed-by: Nathan Chancellor <nathan@kernel.org>
>
> Should this have a fixes tag?

I was debating that, the existing if-check will catch this, just not as 
efficiently.

I'll add the line.

Tom

>
> Fixes: 72b010dc33b9 ("crypto: hisilicon/qm - supports writing QoS int the host")
>
>> ---
>>   drivers/crypto/hisilicon/qm.c | 2 +-
>>   1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/drivers/crypto/hisilicon/qm.c b/drivers/crypto/hisilicon/qm.c
>> index b1fe9c7b8cc89..c906f2e59277b 100644
>> --- a/drivers/crypto/hisilicon/qm.c
>> +++ b/drivers/crypto/hisilicon/qm.c
>> @@ -4379,7 +4379,7 @@ static ssize_t qm_get_qos_value(struct hisi_qm *qm, const char *buf,
>>   		return -EINVAL;
>>   
>>   	ret = qm_qos_value_init(val_buf, val);
>> -	if (*val == 0 || *val > QM_QOS_MAX_VAL || ret) {
>> +	if (ret || *val == 0 || *val > QM_QOS_MAX_VAL) {
>>   		pci_err(qm->pdev, "input qos value is error, please set 1~1000!\n");
>>   		return -EINVAL;
>>   	}
>> -- 
>> 2.26.3
>>