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Subject: Re: [PATCH][next] scsi: target: fix unsigned comparision with less
 than zero
To:     Mike Christie <mchristi@redhat.com>,
        "Martin K . Petersen" <martin.petersen@oracle.com>,
        linux-scsi@vger.kernel.org, target-devel@vger.kernel.org
Cc:     kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20190320163709.28767-1-colin.king@canonical.com>
 <5C9274D9.30706@redhat.com>
From:   Colin Ian King <colin.king@canonical.com>
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Message-ID: <60d7479b-14fb-67a1-17df-2e0b9a5085b6@canonical.com>
Date:   Wed, 20 Mar 2019 17:14:51 +0000
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On 20/03/2019 17:14, Mike Christie wrote:
> On 03/20/2019 11:37 AM, Colin King wrote:
>> From: Colin Ian King <colin.king@canonical.com>
>>
>> Currently an error return is being assigned to an unsigned
>> size_t varianle and then checked if the result is less than
>> zero which will always be false.  Fix this by making ret
> 
> What kernel version was this made against?

today's linux-next

> 
> For Martin's 5.2 queue branch, with these scsi changes it looks like
> strlcpy returns a size_t. And then below it looks like we compare the
> return value from that function to the buffer size and the max len of
> the string we support. We do not seem to check for less than zero.
> 
> 
>> ssize_t rather than a size_t.
>>
>> Fixes: 0322913cab79 ("scsi: target: Add device product id and revision configfs attributes")
>> Signed-off-by: Colin Ian King <colin.king@canonical.com>
>> ---
>>  drivers/target/target_core_configfs.c | 9 ++++++---
>>  1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
>> index 8f3faef235b5..3fe79875b3ac 100644
>> --- a/drivers/target/target_core_configfs.c
>> +++ b/drivers/target/target_core_configfs.c
>> @@ -1267,7 +1267,8 @@ static ssize_t target_wwn_vendor_id_store(struct config_item *item,
>>  	/* +2 to allow for a trailing (stripped) '\n' and null-terminator */
>>  	unsigned char buf[INQUIRY_VENDOR_LEN + 2];
>>  	char *stripped = NULL;
>> -	size_t len, ret;
>> +	size_t len;
>> +	ssize_t ret;
>>  
>>  	len = strlcpy(buf, page, sizeof(buf));
>>  	if (len < sizeof(buf)) {
>> @@ -1322,7 +1323,8 @@ static ssize_t target_wwn_product_id_store(struct config_item *item,
>>  	/* +2 to allow for a trailing (stripped) '\n' and null-terminator */
>>  	unsigned char buf[INQUIRY_MODEL_LEN + 2];
>>  	char *stripped = NULL;
>> -	size_t len, ret;
>> +	size_t len;
>> +	ssize_t ret;
>>  
>>  	len = strlcpy(buf, page, sizeof(buf));
>>  	if (len < sizeof(buf)) {
>> @@ -1377,7 +1379,8 @@ static ssize_t target_wwn_revision_store(struct config_item *item,
>>  	/* +2 to allow for a trailing (stripped) '\n' and null-terminator */
>>  	unsigned char buf[INQUIRY_REVISION_LEN + 2];
>>  	char *stripped = NULL;
>> -	size_t len, ret;
>> +	size_t len;
>> +	ssize_t ret;
>>  
>>  	len = strlcpy(buf, page, sizeof(buf));
>>  	if (len < sizeof(buf)) {
>>