linux-sg2042/net/tipc
Hannes Frederic Sowa f3d3342602 net: rework recvmsg handler msg_name and msg_namelen logic
This patch now always passes msg->msg_namelen as 0. recvmsg handlers must
set msg_namelen to the proper size <= sizeof(struct sockaddr_storage)
to return msg_name to the user.

This prevents numerous uninitialized memory leaks we had in the
recvmsg handlers and makes it harder for new code to accidentally leak
uninitialized memory.

Optimize for the case recvfrom is called with NULL as address. We don't
need to copy the address at all, so set it to NULL before invoking the
recvmsg handler. We can do so, because all the recvmsg handlers must
cope with the case a plain read() is called on them. read() also sets
msg_name to NULL.

Also document these changes in include/linux/net.h as suggested by David
Miller.

Changes since RFC:

Set msg->msg_name = NULL if user specified a NULL in msg_name but had a
non-null msg_namelen in verify_iovec/verify_compat_iovec. This doesn't
affect sendto as it would bail out earlier while trying to copy-in the
address. It also more naturally reflects the logic by the callers of
verify_iovec.

With this change in place I could remove "
if (!uaddr || msg_sys->msg_namelen == 0)
	msg->msg_name = NULL
".

This change does not alter the user visible error logic as we ignore
msg_namelen as long as msg_name is NULL.

Also remove two unnecessary curly brackets in ___sys_recvmsg and change
comments to netdev style.

Cc: David Miller <davem@davemloft.net>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2013-11-20 21:52:30 -05:00
..
Kconfig tipc: add InfiniBand media type 2013-04-17 14:18:33 -04:00
Makefile tipc: introduce new TIPC server infrastructure 2013-06-17 15:53:00 -07:00
addr.c tipc: compress out gratuitous extra carriage returns 2012-04-30 15:53:56 -04:00
addr.h tipc: compress out gratuitous extra carriage returns 2012-04-30 15:53:56 -04:00
bcast.c tipc: message reassembly using fragment chain 2013-11-07 18:30:11 -05:00
bcast.h tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
bearer.c tipc: avoid unnecessary lookup for tipc bearer instance 2013-10-18 13:20:43 -04:00
bearer.h tipc: avoid unnecessary lookup for tipc bearer instance 2013-10-18 13:20:43 -04:00
config.c tipc: convert config_lock from spinlock to mutex 2013-06-17 15:53:01 -07:00
config.h tipc: Optimize re-initialization of configuration service 2012-04-26 17:19:07 -04:00
core.c tipc: convert configuration server to use new server facility 2013-06-17 15:53:00 -07:00
core.h net: misc: Remove extern from function prototypes 2013-10-19 19:12:11 -04:00
discover.c tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
discover.h tipc: rename struct link* to struct tipc_link* 2011-12-29 21:53:30 -05:00
eth_media.c tipc: correct return value of recv_msg routine 2013-10-18 13:20:43 -04:00
handler.c tipc: do not use tasklet_disable before tasklet_kill 2012-11-03 15:10:14 -04:00
ib_media.c tipc: correct return value of recv_msg routine 2013-10-18 13:20:43 -04:00
link.c tipc: fix dereference before check warning 2013-11-15 03:11:06 -05:00
link.h tipc: message reassembly using fragment chain 2013-11-07 18:30:11 -05:00
log.c tipc: remove print_buf and deprecated log buffer code 2012-07-13 19:34:43 -04:00
msg.c tipc: remove iovec length parameter from all sending functions 2013-10-18 13:20:42 -04:00
msg.h tipc: message reassembly using fragment chain 2013-11-07 18:30:11 -05:00
name_distr.c tipc: eliminate an unnecessary cast of node variable 2012-11-22 14:33:28 -05:00
name_distr.h [NET] TIPC: Fix whitespace errors. 2007-02-10 23:20:15 -08:00
name_table.c tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
name_table.h tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
net.c tipc: change tipc_net_start routine return value type 2012-08-20 02:26:30 -07:00
net.h tipc: change tipc_net_start routine return value type 2012-08-20 02:26:30 -07:00
netlink.c genetlink: only pass array to genl_register_family_with_ops() 2013-11-19 16:39:05 -05:00
node.c tipc: message reassembly using fragment chain 2013-11-07 18:30:11 -05:00
node.h tipc: message reassembly using fragment chain 2013-11-07 18:30:11 -05:00
node_subscr.c tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
node_subscr.h tipc: compress out gratuitous extra carriage returns 2012-04-30 15:53:56 -04:00
port.c tipc: remove iovec length parameter from all sending functions 2013-10-18 13:20:42 -04:00
port.h tipc: remove iovec length parameter from all sending functions 2013-10-18 13:20:42 -04:00
ref.c tipc: use standard printk shortcut macros (pr_err etc.) 2012-07-13 19:24:44 -04:00
ref.h tipc: cleanup function namespace 2010-10-16 11:13:24 -07:00
server.c tipc: fix oops when creating server socket fails 2013-08-01 15:54:33 -07:00
server.h tipc: introduce new TIPC server infrastructure 2013-06-17 15:53:00 -07:00
socket.c net: rework recvmsg handler msg_name and msg_namelen logic 2013-11-20 21:52:30 -05:00
subscr.c tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
subscr.h tipc: cosmetic realignment of function arguments 2013-06-17 15:53:01 -07:00
sysctl.c tipc: change socket buffer overflow control to respect sk_rcvbuf 2013-06-17 15:53:00 -07:00