From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Ahern <dsahern@gmail.com>
Subject: Re: [PATCH net] net: enable interface alias removal via rtnl
Date: Fri, 6 Oct 2017 12:18:44 -0600
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References: <20171005101940.28550-1-nicolas.dichtel@6wind.com>
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Cc: netdev@vger.kernel.org, Oliver Hartkopp <oliver@hartkopp.net>,
        Stephen Hemminger <stephen@networkplumber.org>
To: Nicolas Dichtel <nicolas.dichtel@6wind.com>, davem@davemloft.net
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On 10/5/17 4:19 AM, Nicolas Dichtel wrote:
> IFLA_IFALIAS is defined as NLA_STRING. It means that the minimal length of
> the attribute is 1 ("\0"). However, to remove an alias, the attribute
> length must be 0 (see dev_set_alias()).

why not add a check in dev_set_alias that if len is 1 and the 1
character is '\0' it means remove the alias?

> 
> Let's define the type to NLA_BINARY, so that the alias can be removed.

that changes the uapi