From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH] inet: dont set inet_rcv_saddr in connect()
Date: Wed, 08 Sep 2010 07:52:51 +0200
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To: David Miller <davem@davemloft.net>
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Le mardi 07 septembre 2010 =C3=A0 22:36 -0700, David Miller a =C3=A9cri=
t :
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Wed, 08 Sep 2010 06:57:37 +0200
>=20
> >    Document that connect() also sets local address, and that before
> > doing a second connect() to change remote address, its mandatory to
> > first issue a connect(AF_UNSPEC) to clear local address (if not loc=
ked
> > by a prior bind() call)
>=20
> For connectionless sockets, the application may connect() as many
> times as it wishes to change the remote address.  The local address
> remains set if it were set before such a re-associating connect().
>=20
> It need only issue a connect(AF_UNSPEC) to make the socket have no
> remote association, and as you state this operation will also wipe ou=
t
> any local address settings not created by a bind() call.
>=20
> And nicely our man pages are very clear about this :-) as is BSD and
> Steven's volume 2.
>=20
> This has been legal for decades, so we have to keep working this way.

Yes, its also buggy, if 2nd remote address is not reachable on same int=
erface.
Even if we try a connect(AF_UNSPEC), the local address stay as is :

after bind(port 5555) local addr=3D0x0:5555=20
after connect(123) local addr=3D0x7f000001:5555 remote addr=3D0x7f00000=
1:123=20
Could not connect, errno=3D22
after connect(AF_UNSPEC) local addr=3D0x7f000001:5555=20
connect: Invalid argument

I'll work on UDP fix anyway.