linux-stable.git/net/mac80211, branch v3.14

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem

2014-03-07T20:09:32+00:00

mac80211: clear sequence/fragment number in QoS-null frames

2014-03-05T14:49:54+00:00

Avoid leaking data by sending uninitialized memory and setting an
invalid (non-zero) fragment number (the sequence number is ignored
anyway) by setting the seq_ctrl field to zero.

Cc: stable@vger.kernel.org
Fixes: 3f52b7e328c5 ("mac80211: mesh power save basics")
Fixes: ce662b44ce22 ("mac80211: send (QoS) Null if no buffered frames")
Reviewed-by: Emmanuel Grumbach 
Signed-off-by: Johannes Berg

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem

2014-03-03T19:34:45+00:00

mac80211: consider virtual mon when calculating min_def

2014-03-03T12:48:13+00:00

When calculating the current max bw required for
a channel context, we didn't consider the virtual
monitor interface, resulting in its channel context
being narrower than configured.

This broke monitor mode with iwlmvm, which uses the
minimal width.

Reported-by: Ido Yariv 
Signed-off-by: Eliad Peller 
Signed-off-by: Johannes Berg

Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless into for-davem

2014-02-27T20:05:51+00:00

mac80211: fix association to 20/40 MHz VHT networks

2014-02-27T19:53:01+00:00

When a VHT network uses 20 or 40 MHz as per the HT operation
information, the channel center frequency segment 0 field in
the VHT operation information is reserved, so ignore it.

This fixes association with such networks when the AP puts 0
into the field, previously we'd disconnect due to an invalid
channel with the message
wlan0: AP VHT information is invalid, disable VHT

Cc: stable@vger.kernel.org
Fixes: f2d9d270c15ae ("mac80211: support VHT association")
Reported-by: Tim Nelson 
Signed-off-by: Johannes Berg

mac80211: don't validate unchanged AP bandwidth while tracking

2014-02-24T09:16:40+00:00

The MLME code in mac80211 must track whether or not the AP changed
bandwidth, but if there's no change while tracking it shouldn't do
anything, otherwise regulatory updates can make it impossible to
connect to certain APs if the regulatory database doesn't match the
information from the AP. See the precise scenario described in the
code.

This still leaves some possible problems with CSA or if the AP
actually changed bandwidth, but those cases are less common and
won't completely prevent using it.

This fixes https://bugzilla.kernel.org/show_bug.cgi?id=70881

Cc: stable@vger.kernel.org
Reported-and-tested-by: Nate Carlson 
Signed-off-by: Johannes Berg

mac80211: fix station wakeup powersave race

2014-02-20T10:54:09+00:00

Consider the following (relatively unlikely) scenario:
 1) station goes to sleep while frames are buffered in driver
 2) driver blocks wakeup (until no more frames are buffered)
 3) station wakes up again
 4) driver unblocks wakeup

In this case, the current mac80211 code will do the following:
 1) WLAN_STA_PS_STA set
 2) WLAN_STA_PS_DRIVER set
 3) - nothing -
 4) WLAN_STA_PS_DRIVER cleared

As a result, no frames will be delivered to the client, even
though it is awake, until it sends another frame to us that
triggers ieee80211_sta_ps_deliver_wakeup() in sta_ps_end().

Since we now take the PS spinlock, we can fix this while at
the same time removing the complexity with the pending skb
queue function. This was broken since my commit 50a9432daeec
("mac80211: fix powersaving clients races") due to removing
the clearing of WLAN_STA_PS_STA in the RX path.

While at it, fix a cleanup path issue when a station is
removed while the driver is still blocking its wakeup.

Signed-off-by: Johannes Berg

mac80211: insert stations before adding to driver

2014-02-20T09:34:33+00:00

There's a race condition in mac80211 because we add stations
to the internal lists after adding them to the driver, which
means that (for example) the following can happen:
 1. a station connects and is added
 2. first, it is added to the driver
 3. then, it is added to the mac80211 lists

If the station goes to sleep between steps 2 and 3, and the
firmware/hardware records it as being asleep, mac80211 will
never instruct the driver to wake it up again as it never
realized it went to sleep since the RX path discarded the
frame as a "spurious class 3 frame", no station entry was
present yet.

Fix this by adding the station in software first, and only
then adding it to the driver. That way, any state that the
driver changes will be reflected properly in mac80211's
station state. The problematic part is the roll-back if the
driver fails to add the station, in that case a bit more is
needed. To not make that overly complex prevent starting BA
sessions in the meantime.

Signed-off-by: Johannes Berg

mac80211: fix AP powersave TX vs. wakeup race

2014-02-20T09:32:29+00:00

There is a race between the TX path and the STA wakeup: while
a station is sleeping, mac80211 buffers frames until it wakes
up, then the frames are transmitted. However, the RX and TX
path are concurrent, so the packet indicating wakeup can be
processed while a packet is being transmitted.

This can lead to a situation where the buffered frames list
is emptied on the one side, while a frame is being added on
the other side, as the station is still seen as sleeping in
the TX path.

As a result, the newly added frame will not be send anytime
soon. It might be sent much later (and out of order) when the
station goes to sleep and wakes up the next time.

Additionally, it can lead to the crash below.

Fix all this by synchronising both paths with a new lock.
Both path are not fastpath since they handle PS situations.

In a later patch we'll remove the extra skb queue locks to
reduce locking overhead.

BUG: unable to handle kernel
NULL pointer dereference at 000000b0
IP: [] ieee80211_report_used_skb+0x11/0x3e0 [mac80211]
*pde = 00000000
Oops: 0000 [#1] SMP DEBUG_PAGEALLOC
EIP: 0060:[] EFLAGS: 00210282 CPU: 1
EIP is at ieee80211_report_used_skb+0x11/0x3e0 [mac80211]
EAX: e5900da0 EBX: 00000000 ECX: 00000001 EDX: 00000000
ESI: e41d00c0 EDI: e5900da0 EBP: ebe458e4 ESP: ebe458b0
 DS: 007b ES: 007b FS: 00d8 GS: 00e0 SS: 0068
CR0: 8005003b CR2: 000000b0 CR3: 25a78000 CR4: 000407d0
DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
DR6: ffff0ff0 DR7: 00000400
Process iperf (pid: 3934, ti=ebe44000 task=e757c0b0 task.ti=ebe44000)
iwlwifi 0000:02:00.0: I iwl_pcie_enqueue_hcmd Sending command LQ_CMD (#4e), seq: 0x0903, 92 bytes at 3[3]:9
Stack:
 e403b32c ebe458c4 00200002 00200286 e403b338 ebe458cc c10960bb e5900da0
 ff76a6ec ebe458d8 00000000 e41d00c0 e5900da0 ebe458f0 ff6f1b75 e403b210
 ebe4598c ff723dc1 00000000 ff76a6ec e597c978 e403b758 00000002 00000002
Call Trace:
 [] ieee80211_free_txskb+0x15/0x20 [mac80211]
 [] invoke_tx_handlers+0x1661/0x1780 [mac80211]
 [] ieee80211_tx+0x75/0x100 [mac80211]
 [] ieee80211_xmit+0x8f/0xc0 [mac80211]
 [] ieee80211_subif_start_xmit+0x4fe/0xe20 [mac80211]
 [] dev_hard_start_xmit+0x450/0x950
 [] sch_direct_xmit+0xa9/0x250
 [] __qdisc_run+0x4b/0x150
 [] dev_queue_xmit+0x2c2/0xca0

Cc: stable@vger.kernel.org
Reported-by: Yaara Rozenblum 
Signed-off-by: Emmanuel Grumbach 
Reviewed-by: Stanislaw Gruszka 
[reword commit log, use a separate lock]
Signed-off-by: Johannes Berg