Re: [PATCH] linux 2.9.10-rc1: Fix oops in unix_dgram_sendmsg when using SELinux and SOCK_SEQPACKET

On Iau, 2004-11-18 at 03:42, James Morris wrote:

quoted

Well, my reading of socket(2) suggests that it's _not_ supposed to work.

sendto() on a non connected socket should fail with ENOTCONN.

Not entirely true at all. A network protocol can implement lazy binding
and
do implicit binding on the sendto. Other protocols might not actually
have
a receiving component so have no bind() functionality at all.

According to the send(2) man page, we may return EISCONN if the address
and addr length are not NULL and zero.  I think that the man page is
incorrect.  Posix says that EISCONN means "A destination address was
specified and the socket is already connected", not "A destination address
was specified and the socket is connected mode".  i.e. we should only 
return EISCONN if the socket is in a connected state.

POSIX 1003.1g draft 6.4 permits a user to pass a "null" address for
various things. Indeed some systems implement send() as sendto() with a
NULL, 0 address component and some user space does likewise. It also has
a lot to say on the other cases although I don't think it ever fully got
past draft state.

You also want to look at TCP/IP illustrated to see some of the
assumptions handed down from on high by BSD and which should not be
broken.