Re: [PATCH v2] netlink: Return unsigned value for nla_len()

[Nicolas Dichtel]

Le 04/12/2023 à 23:21, Kees Cook a écrit :
[snip]
>>> diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h
>>> index f87aaf28a649..270feed9fd63 100644
>>> --- a/include/uapi/linux/netlink.h
>>> +++ b/include/uapi/linux/netlink.h
>>> @@ -247,7 +247,7 @@ struct nlattr {
>>>  
>>>  #define NLA_ALIGNTO		4
>>>  #define NLA_ALIGN(len)		(((len) + NLA_ALIGNTO - 1) & ~(NLA_ALIGNTO - 1))
>>> -#define NLA_HDRLEN		((int) NLA_ALIGN(sizeof(struct nlattr)))
>>> +#define NLA_HDRLEN		((__u16) NLA_ALIGN(sizeof(struct nlattr)))
>> I wonder if this may break the compilation of some userspace tools with errors
>> like comparing signed and unsigned values.
> 
> Should I drop this part, then?
> 
Yes please.


Thank you,
Nicolas