linux.git/fs/dlm/netlink.c, branch v5.2

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 193

2019-05-30T18:29:21+00:00

Based on 1 normalized pattern(s):

  this copyrighted material is made available to anyone wishing to use
  modify copy or redistribute it subject to the terms and conditions
  of the gnu general public license v 2

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 45 file(s).

Signed-off-by: Thomas Gleixner 
Reviewed-by: Richard Fontana 
Reviewed-by: Allison Randal 
Reviewed-by: Steve Winslow 
Reviewed-by: Alexios Zavras 
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190528170027.342746075@linutronix.de
Signed-off-by: Greg Kroah-Hartman

genetlink: optionally validate strictly/dumps

2019-04-27T21:07:22+00:00

Add options to strictly validate messages and dump messages,
sometimes perhaps validating dump messages non-strictly may
be required, so add an option for that as well.

Since none of this can really be applied to existing commands,
set the options everwhere using the following spatch:

    @@
    identifier ops;
    expression X;
    @@
    struct genl_ops ops[] = {
    ...,
     {
            .cmd = X,
    +       .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
            ...
     },
    ...
    };

For new commands one should just not copy the .validate 'opt-out'
flags and thus get strict validation.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

Merge tag 'dlm-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm

2016-12-14T16:31:37+00:00

Pull dlm fixes from David Teigland:
 "This set fixes error reporting for dlm sockets, removes the unbound
  property on the dlm callback workqueue to improve performance, and
  includes a couple trivial changes"

* tag 'dlm-4.10' of git://git.kernel.org/pub/scm/linux/kernel/git/teigland/linux-dlm:
  dlm: fix error return code in sctp_accept_from_sock()
  dlm: don't specify WQ_UNBOUND for the ast callback workqueue
  dlm: remove lock_sock to avoid scheduling while atomic
  dlm: don't save callbacks after accept
  dlm: audit and remove any unnecessary uses of module.h
  dlm: make genl_ops const

genetlink: mark families as __ro_after_init

2016-10-27T20:16:09+00:00

Now genl_register_family() is the only thing (other than the
users themselves, perhaps, but I didn't find any doing that)
writing to the family struct.

In all families that I found, genl_register_family() is only
called from __init functions (some indirectly, in which case
I've add __init annotations to clarifly things), so all can
actually be marked __ro_after_init.

This protects the data structure from accidental corruption.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

genetlink: statically initialize families

2016-10-27T20:16:09+00:00

Instead of providing macros/inline functions to initialize
the families, make all users initialize them statically and
get rid of the macros.

This reduces the kernel code size by about 1.6k on x86-64
(with allyesconfig).

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

genetlink: no longer support using static family IDs

2016-10-27T20:16:09+00:00

Static family IDs have never really been used, the only
use case was the workaround I introduced for those users
that assumed their family ID was also their multicast
group ID.

Additionally, because static family IDs would never be
reserved by the generic netlink code, using a relatively
low ID would only work for built-in families that can be
registered immediately after generic netlink is started,
which is basically only the control family (apart from
the workaround code, which I also had to add code for so
it would reserve those IDs)

Thus, anything other than GENL_ID_GENERATE is flawed and
luckily not used except in the cases I mentioned. Move
those workarounds into a few lines of code, and then get
rid of GENL_ID_GENERATE entirely, making it more robust.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

dlm: make genl_ops const

2016-10-19T16:00:03+00:00

This table contains function points and should be const.

Signed-off-by: Stephen Hemminger 
Signed-off-by: David Teigland

netlink: make nlmsg_end() and genlmsg_end() void

2015-01-18T06:03:45+00:00

Contrary to common expectations for an "int" return, these functions
return only a positive value -- if used correctly they cannot even
return 0 because the message header will necessarily be in the skb.

This makes the very common pattern of

  if (genlmsg_end(...) < 0) { ... }

be a whole bunch of dead code. Many places also simply do

  return nlmsg_end(...);

and the caller is expected to deal with it.

This also commonly (at least for me) causes errors, because it is very
common to write

  if (my_function(...))
    /* error condition */

and if my_function() does "return nlmsg_end()" this is of course wrong.

Additionally, there's not a single place in the kernel that actually
needs the message length returned, and if anyone needs it later then
it'll be very easy to just use skb->len there.

Remove this, and make the functions void. This removes a bunch of dead
code as described above. The patch adds lines because I did

-	return nlmsg_end(...);
+	nlmsg_end(...);
+	return 0;

I could have preserved all the function's return values by returning
skb->len, but instead I've audited all the places calling the affected
functions and found that none cared. A few places actually compared
the return value with <= 0 in dump functionality, but that could just
be changed to < 0 with no change in behaviour, so I opted for the more
efficient version.

One instance of the error I've made numerous times now is also present
in net/phonet/pn_netlink.c in the route_dumpit() function - it didn't
check for <0 or <=0 and thus broke out of the loop every single time.
I've preserved this since it will (I think) have caused the messages to
userspace to be formatted differently with just a single message for
every SKB returned to userspace. It's possible that this isn't needed
for the tools that actually use this, but I don't even know what they
are so couldn't test that changing this behaviour would be acceptable.

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

genetlink: only pass array to genl_register_family_with_ops()

2013-11-19T21:39:05+00:00

As suggested by David Miller, make genl_register_family_with_ops()
a macro and pass only the array, evaluating ARRAY_SIZE() in the
macro, this is a little safer.

The openvswitch has some indirection, assing ops/n_ops directly in
that code. This might ultimately just assign the pointers in the
family initializations, saving the struct genl_family_and_ops and
code (once mcast groups are handled differently.)

Signed-off-by: Johannes Berg 
Signed-off-by: David S. Miller

netlink: Rename pid to portid to avoid confusion

2012-09-10T19:30:41+00:00

It is a frequent mistake to confuse the netlink port identifier with a
process identifier.  Try to reduce this confusion by renaming fields
that hold port identifiers portid instead of pid.

I have carefully avoided changing the structures exported to
userspace to avoid changing the userspace API.

I have successfully built an allyesconfig kernel with this change.

Signed-off-by: "Eric W. Biederman" 
Acked-by: Stephen Hemminger 
Signed-off-by: David S. Miller