linux-toradex.git/net/rds/send.c, branch v3.19.6

net: introduce helper macro for_each_cmsghdr

2014-12-11T03:41:55+00:00

Introduce helper macro for_each_cmsghdr as a wrapper of the enumerating
cmsghdr from msghdr, just cleanup.

Signed-off-by: Gu Zheng 
Signed-off-by: David S. Miller

put iov_iter into msghdr

2014-12-09T21:29:03+00:00

Note that the code _using_ ->msg_iter at that point will be very
unhappy with anything other than unshifted iovec-backed iov_iter.
We still need to convert users to proper primitives.

Signed-off-by: Al Viro

rds: switch rds_message_copy_from_user() to iov_iter

2014-11-24T10:16:43+00:00

Signed-off-by: Al Viro

net/rds: fix possible double free on sock tear down

2014-10-03T19:52:00+00:00

I got a report of a double free happening at RDS slab cache. One
suspicion was that may be somewhere we were doing a sock_hold/sock_put
on an already freed sock. Thus after providing a kernel with the
following change:

 static inline void sock_hold(struct sock *sk)
 {
-       atomic_inc(&sk->sk_refcnt);
+       if (!atomic_inc_not_zero(&sk->sk_refcnt))
+               WARN(1, "Trying to hold sock already gone: %p (family: %hd)\n",
+                       sk, sk->sk_family);
 }

The warning successfuly triggered:

Trying to hold sock already gone: ffff81f6dda61280 (family: 21)
WARNING: at include/net/sock.h:350 sock_hold()
Call Trace:
  [] :rds:rds_send_remove_from_sock+0xf0/0x21b
[] :rds:rds_send_drop_acked+0xbf/0xcf
[] :rds_rdma:rds_ib_recv_tasklet_fn+0x256/0x2dc
[] tasklet_action+0x8f/0x12b
[] __do_softirq+0x89/0x133
[] call_softirq+0x1c/0x28
[] do_softirq+0x2c/0x7d
[] do_IRQ+0xee/0xf7
[] ret_from_intr+0x0/0xa


Looking at the call chain above, the only way I think this would be
possible is if somewhere we already released the same socket->sock which
is assigned to the rds_message at rds_send_remove_from_sock. Which seems
only possible to happen after the tear down done on rds_release.

rds_release properly calls rds_send_drop_to to drop the socket from any
rds_message, and some proper synchronization is in place to avoid race
with rds_send_drop_acked/rds_send_remove_from_sock. However, I still see
a very narrow window where it may be possible we touch a sock already
released: when rds_release races with rds_send_drop_acked, we check
RDS_MSG_ON_CONN to avoid cleanup on the same rds_message, but in this
specific case we don't clear rm->m_rs. In this case, it seems we could
then go on at rds_send_drop_to and after it returns, the sock is freed
by last sock_put on rds_release, with concurrently we being at
rds_send_remove_from_sock; then at some point in the loop at
rds_send_remove_from_sock we process an rds_message which didn't have
rm->m_rs unset for a freed sock, and a possible sock_hold on an sock
already gone at rds_release happens.

This hopefully address the described condition above and avoids a double
free on "second last" sock_put. In addition, I removed the comment about
socket destruction on top of rds_send_drop_acked: we call rds_send_drop_to
in rds_release and we should have things properly serialized there, thus
I can't see the comment being accurate there.

Signed-off-by: Herton R. Krzesinski 
Signed-off-by: David S. Miller

arch: Mass conversion of smp_mb__*()

2014-04-18T12:20:48+00:00

Mostly scripted conversion of the smp_mb__* barriers.

Signed-off-by: Peter Zijlstra 
Acked-by: Paul E. McKenney 
Link: http://lkml.kernel.org/n/tip-55dhyhocezdw1dg7u19hmh1u@git.kernel.org
Cc: Linus Torvalds 
Cc: linux-arch@vger.kernel.org
Signed-off-by: Ingo Molnar

net: add build-time checks for msg->msg_name size

2014-01-19T07:04:16+00:00

This is a follow-up patch to f3d3342602f8bc ("net: rework recvmsg
handler msg_name and msg_namelen logic").

DECLARE_SOCKADDR validates that the structure we use for writing the
name information to is not larger than the buffer which is reserved
for msg->msg_name (which is 128 bytes). Also use DECLARE_SOCKADDR
consistently in sendmsg code paths.

Signed-off-by: Steffen Hurrle 
Suggested-by: Hannes Frederic Sowa 
Acked-by: Hannes Frederic Sowa 
Signed-off-by: David S. Miller

RDS: fix rds-ping spinlock recursion

2012-10-09T17:57:23+00:00

This is the revised patch for fixing rds-ping spinlock recursion
according to Venkat's suggestions.

RDS ping/pong over TCP feature has been broken for years(2.6.39 to
3.6.0) since we have to set TCP cork and call kernel_sendmsg() between
ping/pong which both need to lock "struct sock *sk". However, this
lock has already been hold before rds_tcp_data_ready() callback is
triggerred. As a result, we always facing spinlock resursion which
would resulting in system panic.

Given that RDS ping is only used to test the connectivity and not for
serious performance measurements, we can queue the pong transmit to
rds_wq as a delayed response.

Reported-by: Dan Carpenter 
CC: Venkat Venkatsubra 
CC: David S. Miller 
CC: James Morris 
Signed-off-by: Jie Liu 
Signed-off-by: David S. Miller

Remove printk from rds_sendmsg

2012-03-20T20:12:11+00:00

no socket layer outputs a message for this error and neither should rds.

Signed-off-by: Dave Jones 
Signed-off-by: David S. Miller

net: Add export.h for EXPORT_SYMBOL/THIS_MODULE to non-modules

2011-10-31T23:30:30+00:00

These files are non modular, but need to export symbols using
the macros now living in export.h -- call out the include so
that things won't break when we remove the implicit presence
of module.h from everywhere.

Signed-off-by: Paul Gortmaker

net: add moduleparam.h for users of module_param/MODULE_PARM_DESC

2011-10-31T23:30:29+00:00

These files were getting access to these two via the implicit
presence of module.h everywhere.  They aren't modules, so they
don't need the full module.h inclusion though.

Signed-off-by: Paul Gortmaker