Re: [PATCH v4 01/10] crypto: hisilicon/qm - fix wrong release after using strsep

Re: [PATCH v4 01/10] crypto: hisilicon/qm - fix wrong release after using strsep

[shenyang (M)]

On 2020/8/5 2:34, Markus Elfring wrote:
> …
>> +++ b/drivers/crypto/hisilicon/qm.c
>> @@ -1420,16 +1420,17 @@ static int qm_dbg_help(struct hisi_qm *qm, char *s)
> …
>> +	s_tmp = s;
>>  	presult = strsep(&s, " ");
>>  	if (!presult) {
>> -		kfree(s);
>> +		kfree(s_tmp);
>>  		return -EINVAL;
>>  	}
>
> -		kfree(s);
> -		return -EINVAL;
> +		ret = -EINVAL;
> +		goto free_tmp;
>
> I suggest to add a jump target for the desired exception handling.
>
> Regards,
> Markus
>
> .
>

Thanks for your review. There is only one error branch need to do
something uninit. So I think the jump is not necessary and will
affect code reading.:)

Thanks,
Yang

Re: [v4 01/10] crypto: hisilicon/qm - fix wrong release after using strsep

[shenyang (M)]

On 2020/8/5 14:04, Markus Elfring wrote:
>> Thanks for your review. There is only one error branch need to do
>> something uninit. So I think the jump is not necessary and will
>> affect code reading.:)
>
> How does this concern fit to the Linux coding style?
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/coding-style.rst?id=4da9f3302615f4191814f826054846bf843e24fa#n481
>
> Regards,
> Markus
>
> .
>

Got it, I'll fix this.

Thanks,
Yang

Re: [v4 01/10] crypto: hisilicon/qm - fix wrong release after using strsep

[shenyang (M)]

On 2020/8/6 15:23, Markus Elfring wrote:
> Would you become interested to look if any other software components
> would be similarly affected?

Yeah, I'll check the rest and fix if any and send those in  a
clean up patch.

Thanks,
Yang

[PATCH v4 01/10] crypto: hisilicon/qm - fix wrong release after using strsep

[Yang Shen]

From: Sihang Chen <chensihang1@hisilicon.com>

Save the string address before pass to strsep, release it at end.
Because strsep will update the string address to point after the
token.

Fixes: c31dc9fe165d("crypto: hisilicon/qm - add DebugFS for xQC and...")
Signed-off-by: Sihang Chen <chensihang1@hisilicon.com>
Signed-off-by: Yang Shen <shenyang39@huawei.com>
Reviewed-by: Zhou Wang <wangzhou1@hisilicon.com>
---
 drivers/crypto/hisilicon/qm.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/drivers/crypto/hisilicon/qm.c b/drivers/crypto/hisilicon/qm.c
index 6527c53..ffb28cc 100644
--- a/drivers/crypto/hisilicon/qm.c
+++ b/drivers/crypto/hisilicon/qm.c
@@ -1420,16 +1420,17 @@ static int qm_dbg_help(struct hisi_qm *qm, char *s)
 static int qm_cmd_write_dump(struct hisi_qm *qm, const char *cmd_buf)
 {
 	struct device *dev = &qm->pdev->dev;
-	char *presult, *s;
+	char *presult, *s, *s_tmp;
 	int ret;
 
 	s = kstrdup(cmd_buf, GFP_KERNEL);
 	if (!s)
 		return -ENOMEM;
 
+	s_tmp = s;
 	presult = strsep(&s, " ");
 	if (!presult) {
-		kfree(s);
+		kfree(s_tmp);
 		return -EINVAL;
 	}
 
@@ -1459,7 +1460,7 @@ static int qm_cmd_write_dump(struct hisi_qm *qm, const char *cmd_buf)
 	if (ret)
 		dev_info(dev, "Please echo help\n");
 
-	kfree(s);
+	kfree(s_tmp);
 
 	return ret;
 }
-- 
2.7.4