From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: inet_hash_connect: source port allocation
Date: Mon, 29 Nov 2010 19:46:03 +0100
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Cc: NetDev <netdev@vger.kernel.org>,
	Stephen Hemminger <shemminger@vyatta.com>
To: John Haxby <john.haxby@oracle.com>
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Le lundi 29 novembre 2010 =C3=A0 18:29 +0000, John Haxby a =C3=A9crit :

> Sorry,  I think I phrased my question badly.
>=20
> inet_csk_get_port() starts its search for a free port with
>=20
>      smallest_rover =3D rover =3D net_random() % remaining + low;
>=20
> whereas __inet_hash_connect() basically misses out that call to=20
> net_random() so you get a predictable port number.
>=20
> Is there any good reason why that is the case?
>=20

It seems random select was done at bind() time only in commit
6df716340da3a6f ([TCP/DCCP]: Randomize port selection)

It probably should be done in autobind too.