linux/net/unix
Eric Dumazet 9f6f9af769 af_unix: MSG_TRUNC support for dgram sockets
Piergiorgio Beruto expressed the need to fetch size of first datagram in
queue for AF_UNIX sockets and suggested a patch against SIOCINQ ioctl.

I suggested instead to implement MSG_TRUNC support as a recv() input
flag, as already done for RAW, UDP & NETLINK sockets.

len = recv(fd, &byte, 1, MSG_PEEK | MSG_TRUNC);

MSG_TRUNC asks recv() to return the real length of the packet, even when
is was longer than the passed buffer.

There is risk that a userland application used MSG_TRUNC by accident
(since it had no effect on af_unix sockets) and this might break after
this patch.

Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Tested-by: Piergiorgio Beruto <piergiorgio.beruto@gmail.com>
CC: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2012-02-22 14:47:02 -05:00
..
Kconfig net: Default UDP and UNIX diag to 'n'. 2012-01-07 12:13:06 -08:00
Makefile unix_diag: Write it into kbuild 2011-12-16 13:48:29 -05:00
af_unix.c af_unix: MSG_TRUNC support for dgram sockets 2012-02-22 14:47:02 -05:00
diag.c unix_diag: Fixup RQLEN extension report 2011-12-30 16:46:02 -05:00
garbage.c Allow passing O_PATH descriptors via SCM_RIGHTS datagrams 2011-03-15 02:21:45 -04:00
sysctl_net_unix.c include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h 2010-03-30 22:02:32 +09:00