Re: [PATCH 2/2] s390: Fix possibly wrong size in strncmp (smsglucv)

[Andreas Schwab <schwab@linux-m68k.org>]

Jesper Juhl <jj@chaosbits.net> writes:

> On Sat, 29 Jan 2011, Stefan Weil wrote:
>
>> This error was reported by cppcheck:
>> drivers/s390/net/smsgiucv.c:63: error: Using sizeof for array given as function argument returns the size of pointer.
>> 
>> Although there is no runtime problem as long as sizeof(u8 *) == 8,
>> this misleading code should get fixed.
>> 
>> Cc: Ursula Braun <ursula.braun@de.ibm.com>
>> Cc: linux390@de.ibm.com
>> Cc: Frank Blaschka <blaschka@linux.vnet.ibm.com>
>> Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
>> Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
>> Cc: linux-s390@vger.kernel.org
>> Cc: linux-kernel@vger.kernel.org
>> Signed-off-by: Stefan Weil <weil@mail.berlios.de>
>> ---
>>  drivers/s390/net/smsgiucv.c |    2 +-
>>  1 files changed, 1 insertions(+), 1 deletions(-)
>> 
>> diff --git a/drivers/s390/net/smsgiucv.c b/drivers/s390/net/smsgiucv.c
>> index 65e1cf1..207b7d7 100644
>> --- a/drivers/s390/net/smsgiucv.c
>> +++ b/drivers/s390/net/smsgiucv.c
>> @@ -60,7 +60,7 @@ static struct iucv_handler smsg_handler = {
>>  static int smsg_path_pending(struct iucv_path *path, u8 ipvmid[8],
>>  			     u8 ipuser[16])
>>  {
>> -	if (strncmp(ipvmid, "*MSG    ", sizeof(ipvmid)) != 0)
>> +	if (strncmp(ipvmid, "*MSG    ", 8) != 0)
>
> Hmm, shouldn't this really be  ARRAY_SIZE(ipvmid)  ??

ARRAY_SIZE does not work for the same reason why sizeof does not work:
ipvmid is not an array, it's a pointer.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
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