drivers/net/niu.c: memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len)?

drivers/net/niu.c: memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len)?

[Roel Kluin]

in drivers/net/niu.c, line 6406, 6286 and 7173:

memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len);

I noticed that "

memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len)

occurs much more often (15x). could it be that the first two arguments
are swapped in niu.c?

Re: drivers/net/niu.c: memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len)?

[David Miller]

From: Roel Kluin <12o3l@tiscali.nl>
Date: Thu, 20 Mar 2008 22:01:02 +0100

> in drivers/net/niu.c, line 6406, 6286 and 7173:
> 
> memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len);
> 
> I noticed that "
> 
> memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len)
> 
> occurs much more often (15x). could it be that the first two arguments
> are swapped in niu.c?

No, these calls are correct.  We are probing the device's permanent
ethernet address, we first place it into dev->dev_addr and then we
copy it into dev->perm_addr.

Please try to actually understand the pieces of strcpy and memcpy code
you are "finding bugs" in before posting to the list as these analysis
on false positives are going to eat up a lot of developer time.

I notice you posting several of these kinds of things.

Re: drivers/net/niu.c: memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len)?

[Roel Kluin]

David Miller wrote:
> From: Roel Kluin <12o3l@tiscali.nl>
> Date: Thu, 20 Mar 2008 22:01:02 +0100
> 
>> in drivers/net/niu.c, line 6406, 6286 and 7173:
>>
>> memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len);
>>
>> I noticed that "
>>
>> memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len)
>>
>> occurs much more often (15x). could it be that the first two arguments
>> are swapped in niu.c?
> 
> No, these calls are correct.  We are probing the device's permanent
> ethernet address, we first place it into dev->dev_addr and then we
> copy it into dev->perm_addr.
> 
> Please try to actually understand the pieces of strcpy and memcpy code
> you are "finding bugs" in before posting to the list as these analysis
> on false positives are going to eat up a lot of developer time.

Sorry for the noise (also for sound/sparc/dbri.c) and thanks for your
answers, It takes a lot more time for me to understand the code than it
will do for someone with more knowledge and experience with this driver, 

If drivers/net/niu.c copies in opposite direction compared to 80% of the
other memcpy calls - using these same variable names - and it is not
directly transparent why, My opinion is that either the naming is bad or
there is a lack of comment.

> I notice you posting several of these kinds of things.

Only 2 with the above conditions and patches or not where I was able to
figure it out myself. I don't really understand why you are opposed to
these questions.

Re: drivers/net/niu.c: memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len)?

[Kalle Valo]

Roel Kluin <12o3l@tiscali.nl> writes:

>> I notice you posting several of these kinds of things.
>
> Only 2 with the above conditions and patches or not where I was able to
> figure it out myself. I don't really understand why you are opposed to
> these questions.

Because it will take developer's time from fixing real bugs. Time is
scarce and email takes way too much of people's time already. You will
understand this when you start getting too many emails.

-- 
Kalle Valo

drivers/net/niu.c: memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len)?

[Roel Kluin]

in drivers/net/niu.c, line 6406, 6286 and 7173:

memcpy(dev->dev_addr, dev->perm_addr, dev->addr_len);

I noticed that "

memcpy(dev->perm_addr, dev->dev_addr, dev->addr_len)

occurs much more often (15x). could it be that the first two arguments
are swapped in niu.c?