<feed xmlns='http://www.w3.org/2005/Atom'>
<title>lwn.git/drivers/net/wireless/mac80211_hwsim.c, branch docs-4.16</title>
<subtitle>Linux kernel documentation tree maintained by Jonathan Corbet</subtitle>
<id>http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-4.16</id>
<link rel='self' href='http://mirrors.hust.edu.cn/git/lwn.git/atom?h=docs-4.16'/>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/'/>
<updated>2017-11-20T15:57:15+00:00</updated>
<entry>
<title>mac80211_hwsim: Fix memory leak in hwsim_new_radio_nl()</title>
<updated>2017-11-20T15:57:15+00:00</updated>
<author>
<name>Ben Hutchings</name>
<email>ben.hutchings@codethink.co.uk</email>
</author>
<published>2017-11-10T18:48:50+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=67bd52386125ce1159c0581cbcd2740addf33cd4'/>
<id>urn:sha1:67bd52386125ce1159c0581cbcd2740addf33cd4</id>
<content type='text'>
hwsim_new_radio_nl() now copies the name attribute in order to add a
null-terminator.  mac80211_hwsim_new_radio() (indirectly) copies it
again into the net_device structure, so the first copy is not used or
freed later.  Free the first copy before returning.

Fixes: ff4dd73dd2b4 ("mac80211_hwsim: check HWSIM_ATTR_RADIO_NAME length")
Signed-off-by: Ben Hutchings &lt;ben.hutchings@codethink.co.uk&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
</entry>
<entry>
<title>genetlink: fix genlmsg_nlhdr()</title>
<updated>2017-11-16T01:49:00+00:00</updated>
<author>
<name>Michal Kubecek</name>
<email>mkubecek@suse.cz</email>
</author>
<published>2017-11-15T12:09:32+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=0a833c29d89656025443cb9f0ebff7052dd95ce0'/>
<id>urn:sha1:0a833c29d89656025443cb9f0ebff7052dd95ce0</id>
<content type='text'>
According to the description, first argument of genlmsg_nlhdr() points to
what genlmsg_put() returns, i.e. beginning of user header. Therefore we
should only subtract size of genetlink header and netlink message header,
not user header.

This also means we don't need to pass the pointer to genetlink family and
the same is true for genl_dump_check_consistent() which is the only caller
of genlmsg_nlhdr(). (Note that at the moment, these functions are only
used for families which do not have user header so that they are not
affected.)

Fixes: 670dc2833d14 ("netlink: advertise incomplete dumps")
Signed-off-by: Michal Kubecek &lt;mkubecek@suse.cz&gt;
Reviewed-by: Johannes Berg &lt;johannes@sipsolutions.net&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next</title>
<updated>2017-11-15T19:56:19+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2017-11-15T19:56:19+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=5bbcc0f595fadb4cac0eddc4401035ec0bd95b09'/>
<id>urn:sha1:5bbcc0f595fadb4cac0eddc4401035ec0bd95b09</id>
<content type='text'>
Pull networking updates from David Miller:
 "Highlights:

   1) Maintain the TCP retransmit queue using an rbtree, with 1GB
      windows at 100Gb this really has become necessary. From Eric
      Dumazet.

   2) Multi-program support for cgroup+bpf, from Alexei Starovoitov.

   3) Perform broadcast flooding in hardware in mv88e6xxx, from Andrew
      Lunn.

   4) Add meter action support to openvswitch, from Andy Zhou.

   5) Add a data meta pointer for BPF accessible packets, from Daniel
      Borkmann.

   6) Namespace-ify almost all TCP sysctl knobs, from Eric Dumazet.

   7) Turn on Broadcom Tags in b53 driver, from Florian Fainelli.

   8) More work to move the RTNL mutex down, from Florian Westphal.

   9) Add 'bpftool' utility, to help with bpf program introspection.
      From Jakub Kicinski.

  10) Add new 'cpumap' type for XDP_REDIRECT action, from Jesper
      Dangaard Brouer.

  11) Support 'blocks' of transformations in the packet scheduler which
      can span multiple network devices, from Jiri Pirko.

  12) TC flower offload support in cxgb4, from Kumar Sanghvi.

  13) Priority based stream scheduler for SCTP, from Marcelo Ricardo
      Leitner.

  14) Thunderbolt networking driver, from Amir Levy and Mika Westerberg.

  15) Add RED qdisc offloadability, and use it in mlxsw driver. From
      Nogah Frankel.

  16) eBPF based device controller for cgroup v2, from Roman Gushchin.

  17) Add some fundamental tracepoints for TCP, from Song Liu.

  18) Remove garbage collection from ipv6 route layer, this is a
      significant accomplishment. From Wei Wang.

  19) Add multicast route offload support to mlxsw, from Yotam Gigi"

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2177 commits)
  tcp: highest_sack fix
  geneve: fix fill_info when link down
  bpf: fix lockdep splat
  net: cdc_ncm: GetNtbFormat endian fix
  openvswitch: meter: fix NULL pointer dereference in ovs_meter_cmd_reply_start
  netem: remove unnecessary 64 bit modulus
  netem: use 64 bit divide by rate
  tcp: Namespace-ify sysctl_tcp_default_congestion_control
  net: Protect iterations over net::fib_notifier_ops in fib_seq_sum()
  ipv6: set all.accept_dad to 0 by default
  uapi: fix linux/tls.h userspace compilation error
  usbnet: ipheth: prevent TX queue timeouts when device not ready
  vhost_net: conditionally enable tx polling
  uapi: fix linux/rxrpc.h userspace compilation errors
  net: stmmac: fix LPI transitioning for dwmac4
  atm: horizon: Fix irq release error
  net-sysfs: trigger netlink notification on ifalias change via sysfs
  openvswitch: Using kfree_rcu() to simplify the code
  openvswitch: Make local function ovs_nsh_key_attr_size() static
  openvswitch: Fix return value check in ovs_meter_cmd_features()
  ...
</content>
</entry>
<entry>
<title>locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns to READ_ONCE()/WRITE_ONCE()</title>
<updated>2017-10-25T09:01:08+00:00</updated>
<author>
<name>Mark Rutland</name>
<email>mark.rutland@arm.com</email>
</author>
<published>2017-10-23T21:07:29+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=6aa7de059173a986114ac43b8f50b297a86f09a8'/>
<id>urn:sha1:6aa7de059173a986114ac43b8f50b297a86f09a8</id>
<content type='text'>
Please do not apply this to mainline directly, instead please re-run the
coccinelle script shown below and apply its output.

For several reasons, it is desirable to use {READ,WRITE}_ONCE() in
preference to ACCESS_ONCE(), and new code is expected to use one of the
former. So far, there's been no reason to change most existing uses of
ACCESS_ONCE(), as these aren't harmful, and changing them results in
churn.

However, for some features, the read/write distinction is critical to
correct operation. To distinguish these cases, separate read/write
accessors must be used. This patch migrates (most) remaining
ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following
coccinelle script:

----
// Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and
// WRITE_ONCE()

// $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch

virtual patch

@ depends on patch @
expression E1, E2;
@@

- ACCESS_ONCE(E1) = E2
+ WRITE_ONCE(E1, E2)

@ depends on patch @
expression E;
@@

- ACCESS_ONCE(E)
+ READ_ONCE(E)
----

Signed-off-by: Mark Rutland &lt;mark.rutland@arm.com&gt;
Signed-off-by: Paul E. McKenney &lt;paulmck@linux.vnet.ibm.com&gt;
Cc: Linus Torvalds &lt;torvalds@linux-foundation.org&gt;
Cc: Peter Zijlstra &lt;peterz@infradead.org&gt;
Cc: Thomas Gleixner &lt;tglx@linutronix.de&gt;
Cc: davem@davemloft.net
Cc: linux-arch@vger.kernel.org
Cc: mpe@ellerman.id.au
Cc: shuah@kernel.org
Cc: snitzer@redhat.com
Cc: thor.thayer@linux.intel.com
Cc: tj@kernel.org
Cc: viro@zeniv.linux.org.uk
Cc: will.deacon@arm.com
Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
</content>
</entry>
<entry>
<title>mac80211_hwsim: use dyndbg for debug messages</title>
<updated>2017-09-21T09:42:02+00:00</updated>
<author>
<name>Lubomir Rintel</name>
<email>lkundrak@v3.sk</email>
</author>
<published>2017-09-18T13:56:51+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=62b093b375e3c10ff39896f2a172146cf5df529f'/>
<id>urn:sha1:62b093b375e3c10ff39896f2a172146cf5df529f</id>
<content type='text'>
The mac80211_hwsim doesn't offer a way to disable the debugging output.
Unfortunately, it's pretty chatty, dumping a  lot of stuff into the message
buffer.

This patch changes it to use dyndbg for controlling the debug output.
It's disabled by default, but can be enabled by a module parameter (1),
at runtime (2) or persisted in modprobe.conf (3).

  (1) modprobe mac80211_hwsim dyndbg=+p
  (2) echo "module mac80211_hwsim +p" &gt;/sys/kernel/debug/dynamic_debug/control
  (3) echo "options mac80211_hwsim dyndbg=+p" &gt;&gt;/etc/modprobe.d/my.conf

Signed-off-by: Lubomir Rintel &lt;lkundrak@v3.sk&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
</entry>
<entry>
<title>mac80211_hwsim: Use proper TX power</title>
<updated>2017-09-05T09:28:52+00:00</updated>
<author>
<name>Beni Lev</name>
<email>beni.lev@intel.com</email>
</author>
<published>2017-07-25T08:25:25+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=9de981f507474f326e42117858dc9a9321331ae5'/>
<id>urn:sha1:9de981f507474f326e42117858dc9a9321331ae5</id>
<content type='text'>
In struct ieee80211_tx_info, control.vif pointer and rate_driver_data[0]
falls on the same place, depending on the union usage.
During the whole TX process, the union is referred to as a control struct,
which holds the vif that is later used in the tx flow, especially in order
to derive the used tx power.
Referring direcly to rate_driver_data[0] and assigning a value to it,
overwrites the vif pointer, hence making all later references irrelevant.
Moreover, rate_driver_data[0] isn't used later in the flow in order to
retrieve the channel that it is pointing to.

Cc: stable@vger.kernel.org
Signed-off-by: Beni Lev &lt;beni.lev@intel.com&gt;
Signed-off-by: Luca Coelho &lt;luciano.coelho@intel.com&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
</content>
</entry>
<entry>
<title>networking: make skb_push &amp; __skb_push return void pointers</title>
<updated>2017-06-16T15:48:40+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2017-06-16T12:29:23+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=d58ff35122847a83ba55394e2ae3a1527b6febf5'/>
<id>urn:sha1:d58ff35122847a83ba55394e2ae3a1527b6febf5</id>
<content type='text'>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions return void * and remove all the casts across
the tree, adding a (u8 *) cast only where the unsigned char pointer
was used directly, all done with the following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

    @@
    expression SKB, LEN;
    identifier fn = { skb_push, __skb_push, skb_push_rcsum };
    @@
    - fn(SKB, LEN)[0]
    + *(u8 *)fn(SKB, LEN)

Note that the last part there converts from push(...)[0] to the
more idiomatic *(u8 *)push(...).

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>networking: make skb_put &amp; friends return void pointers</title>
<updated>2017-06-16T15:48:39+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2017-06-16T12:29:21+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=4df864c1d9afb46e2461a9f808d9f11a42d31bad'/>
<id>urn:sha1:4df864c1d9afb46e2461a9f808d9f11a42d31bad</id>
<content type='text'>
It seems like a historic accident that these return unsigned char *,
and in many places that means casts are required, more often than not.

Make these functions (skb_put, __skb_put and pskb_put) return void *
and remove all the casts across the tree, adding a (u8 *) cast only
where the unsigned char pointer was used directly, all done with the
following spatch:

    @@
    expression SKB, LEN;
    typedef u8;
    identifier fn = { skb_put, __skb_put };
    @@
    - *(fn(SKB, LEN))
    + *(u8 *)fn(SKB, LEN)

    @@
    expression E, SKB, LEN;
    identifier fn = { skb_put, __skb_put };
    type T;
    @@
    - E = ((T *)(fn(SKB, LEN)))
    + E = fn(SKB, LEN)

which actually doesn't cover pskb_put since there are only three
users overall.

A handful of stragglers were converted manually, notably a macro in
drivers/isdn/i4l/isdn_bsdcomp.c and, oddly enough, one of the many
instances in net/bluetooth/hci_sock.c. In the former file, I also
had to fix one whitespace problem spatch introduced.

Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>networking: introduce and use skb_put_data()</title>
<updated>2017-06-16T15:48:37+00:00</updated>
<author>
<name>Johannes Berg</name>
<email>johannes.berg@intel.com</email>
</author>
<published>2017-06-16T12:29:20+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=59ae1d127ac0ae404baf414c434ba2651b793f46'/>
<id>urn:sha1:59ae1d127ac0ae404baf414c434ba2651b793f46</id>
<content type='text'>
A common pattern with skb_put() is to just want to memcpy()
some data into the new space, introduce skb_put_data() for
this.

An spatch similar to the one for skb_put_zero() converts many
of the places using it:

    @@
    identifier p, p2;
    expression len, skb, data;
    type t, t2;
    @@
    (
    -p = skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    |
    -p = (t)skb_put(skb, len);
    +p = skb_put_data(skb, data, len);
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, len);
    |
    -memcpy(p, data, len);
    )

    @@
    type t, t2;
    identifier p, p2;
    expression skb, data;
    @@
    t *p;
    ...
    (
    -p = skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    |
    -p = (t *)skb_put(skb, sizeof(t));
    +p = skb_put_data(skb, data, sizeof(t));
    )
    (
    p2 = (t2)p;
    -memcpy(p2, data, sizeof(*p));
    |
    -memcpy(p, data, sizeof(*p));
    )

    @@
    expression skb, len, data;
    @@
    -memcpy(skb_put(skb, len), data, len);
    +skb_put_data(skb, data, len);

(again, manually post-processed to retain some comments)

Reviewed-by: Stephen Hemminger &lt;stephen@networkplumber.org&gt;
Signed-off-by: Johannes Berg &lt;johannes.berg@intel.com&gt;
Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
<entry>
<title>net: Fix inconsistent teardown and release of private netdev state.</title>
<updated>2017-06-07T19:53:24+00:00</updated>
<author>
<name>David S. Miller</name>
<email>davem@davemloft.net</email>
</author>
<published>2017-05-08T16:52:56+00:00</published>
<link rel='alternate' type='text/html' href='http://mirrors.hust.edu.cn/git/lwn.git/commit/?id=cf124db566e6b036b8bcbe8decbed740bdfac8c6'/>
<id>urn:sha1:cf124db566e6b036b8bcbe8decbed740bdfac8c6</id>
<content type='text'>
Network devices can allocate reasources and private memory using
netdev_ops-&gt;ndo_init().  However, the release of these resources
can occur in one of two different places.

Either netdev_ops-&gt;ndo_uninit() or netdev-&gt;destructor().

The decision of which operation frees the resources depends upon
whether it is necessary for all netdev refs to be released before it
is safe to perform the freeing.

netdev_ops-&gt;ndo_uninit() presumably can occur right after the
NETDEV_UNREGISTER notifier completes and the unicast and multicast
address lists are flushed.

netdev-&gt;destructor(), on the other hand, does not run until the
netdev references all go away.

Further complicating the situation is that netdev-&gt;destructor()
almost universally does also a free_netdev().

This creates a problem for the logic in register_netdevice().
Because all callers of register_netdevice() manage the freeing
of the netdev, and invoke free_netdev(dev) if register_netdevice()
fails.

If netdev_ops-&gt;ndo_init() succeeds, but something else fails inside
of register_netdevice(), it does call ndo_ops-&gt;ndo_uninit().  But
it is not able to invoke netdev-&gt;destructor().

This is because netdev-&gt;destructor() will do a free_netdev() and
then the caller of register_netdevice() will do the same.

However, this means that the resources that would normally be released
by netdev-&gt;destructor() will not be.

Over the years drivers have added local hacks to deal with this, by
invoking their destructor parts by hand when register_netdevice()
fails.

Many drivers do not try to deal with this, and instead we have leaks.

Let's close this hole by formalizing the distinction between what
private things need to be freed up by netdev-&gt;destructor() and whether
the driver needs unregister_netdevice() to perform the free_netdev().

netdev-&gt;priv_destructor() performs all actions to free up the private
resources that used to be freed by netdev-&gt;destructor(), except for
free_netdev().

netdev-&gt;needs_free_netdev is a boolean that indicates whether
free_netdev() should be done at the end of unregister_netdevice().

Now, register_netdevice() can sanely release all resources after
ndo_ops-&gt;ndo_init() succeeds, by invoking both ndo_ops-&gt;ndo_uninit()
and netdev-&gt;priv_destructor().

And at the end of unregister_netdevice(), we invoke
netdev-&gt;priv_destructor() and optionally call free_netdev().

Signed-off-by: David S. Miller &lt;davem@davemloft.net&gt;
</content>
</entry>
</feed>
