There is a theoretical race that if hit will trigger
a crash. The race is between when we issue the first
regulatory hint, regulatory_hint_core(), gets processed
by the workqueue and between when the first device
gets registered to the wireless core. This is not easy
to reproduce but it was easy to do so through the
regulatory simulator I have been working on. This
is a port of the fix I implemented there [1].
[1] https://github.com/mcgrof/regsim/commit/a246ccf81f059cb662eee288aa13100f631e4cc8
Cc: stable@vger.kernel.org
Cc: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When a packet is supposed to sent be as an a-MPDU, mac80211 sets
IEEE80211_TX_CTL_AMPDU to let the driver know. On the other
hand, mac80211 configures the driver for aggregration with the
ampdu_action callback.
There is race between these two mechanisms since the following
scenario can occur when the BA agreement is torn down:
Tx softIRQ drv configuration
========== =================
check OPERATIONAL bit
Set the TX_CTL_AMPDU bit in the packet
clear OPERATIONAL bit
stop Tx AGG
Pass Tx packet to the driver.
In that case the driver would get a packet with TX_CTL_AMPDU set
although it has already been notified that the BA session has been
torn down.
To fix this, we need to synchronize all the Qdisc activity after we
cleared the OPERATIONAL bit. After that step, all the following
packets will be buffered until the driver reports it is ready to get
new packets for this RA / TID. This buffering allows not to run into
another race that would send packets with TX_CTL_AMPDU unset while
the driver hasn't been requested to tear down the BA session yet.
This race occurs in practice and iwlwifi complains with a WARN_ON
when it happens.
Cc: stable@kernel.org
Signed-off-by: Emmanuel Grumbach <emmanuel.grumbach@intel.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
If addBA responses comes in just after addba_resp_timer has
expired mac80211 will still accept it and try to open the
aggregation session. This causes drivers to be confused and
in some cases even crash.
This patch fixes the race condition and makes sure that if
addba_resp_timer has expired addBA response is not longer
accepted and we do not try to open half-closed session.
Cc: stable@vger.kernel.org
Signed-off-by: Nikolay Martynov <mar.kolya@gmail.com>
[some adjustments]
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Nikolay noticed (by code review) that mac80211 can
attempt to stop an aggregation session while it is
already being stopped. So to fix it, check whether
stop is already being done and bail out if so.
Also move setting the STOPPING state into the lock
so things are properly atomic.
Cc: stable@vger.kernel.org
Reported-by: Nikolay Martynov <mar.kolya@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
MAC addresses have a fixed length. The current
policy allows passing < ETH_ALEN bytes, which
might result in reading beyond the buffer.
Cc: stable@vger.kernel.org
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
By the time userspace returns with a response to
the regulatory domain request, the wiphy causing
the request might have gone away. If this is so,
reject the update but mark the request as having
been processed anyway.
Cc: Luis R. Rodriguez <lrodriguez@qca.qualcomm.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When the connection monitor timer fires right before
suspend, the following will happen:
timer fires -> monitor_work gets queued
suspend calls ieee80211_sta_quiesce
ieee80211_sta_quiesce:
- deletes timer
- cancels monitor_work synchronously, running it
[note wrong order of these steps]
monitor_work runs, re-arming the timer
later, timer fires while system should be quiesced
This causes a warning:
WARNING: at net/mac80211/util.c:540 ieee80211_can_queue_work+0x35/0x40 [mac80211]()
but is otherwise harmless. I'm not completely sure
this is the scenario Thomas stumbled across, but it
is the only way I can right now see the warning in
a scenario like the one he reported.
Reported-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Commit 4d9d88d1 by Scott James Remnant <keybuk@google.com> added
the .uevent() callback for the regulatory device used during
the platform device registration. The change was done to account
for queuing up udev change requests through udevadm triggers.
The change also meant that upon regulatory core exit we will now
send a uevent() but the uevent() callback, reg_device_uevent(),
also accessed last_request. Right before commiting device suicide
we free'd last_request but never set it to NULL so
platform_device_unregister() would lead to bogus kernel paging
request. Fix this and also simply supress uevents right before
we commit suicide as they are pointless.
This fix is required for kernels >= v2.6.39
$ git describe --contains 4d9d88d1
v2.6.39-rc1~468^2~25^2^2~21
The impact of not having this present is that a bogus paging
access may occur (only read) upon cfg80211 unload time. You
may also get this BUG complaint below. Although Johannes
could not reproduce the issue this fix is theoretically correct.
mac80211_hwsim: unregister radios
mac80211_hwsim: closing netlink
BUG: unable to handle kernel paging request at ffff88001a06b5ab
IP: [<ffffffffa030df9a>] reg_device_uevent+0x1a/0x50 [cfg80211]
PGD 1836063 PUD 183a063 PMD 1ffcb067 PTE 1a06b160
Oops: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
CPU 0
Modules linked in: cfg80211(-) [last unloaded: mac80211]
Pid: 2279, comm: rmmod Tainted: G W 3.1.0-wl+ #663 Bochs Bochs
RIP: 0010:[<ffffffffa030df9a>] [<ffffffffa030df9a>] reg_device_uevent+0x1a/0x50 [cfg80211]
RSP: 0000:ffff88001c5f9d58 EFLAGS: 00010286
RAX: 0000000000000000 RBX: ffff88001d2eda88 RCX: ffff88001c7468fc
RDX: ffff88001a06b5a0 RSI: ffff88001c7467b0 RDI: ffff88001c7467b0
RBP: ffff88001c5f9d58 R08: 000000000000ffff R09: 000000000000ffff
R10: 0000000000000000 R11: 0000000000000001 R12: ffff88001c7467b0
R13: ffff88001d2eda78 R14: ffffffff8164a840 R15: 0000000000000001
FS: 00007f8a91d8a6e0(0000) GS:ffff88001fc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88001a06b5ab CR3: 000000001c62e000 CR4: 00000000000006f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process rmmod (pid: 2279, threadinfo ffff88001c5f8000, task ffff88000023c780)
Stack:
ffff88001c5f9d98 ffffffff812ff7e5 ffffffff8176ab3d ffff88001c7468c2
000000000000ffff ffff88001d2eda88 ffff88001c7467b0 ffff880000114820
ffff88001c5f9e38 ffffffff81241dc7 ffff88001c5f9db8 ffffffff81040189
Call Trace:
[<ffffffff812ff7e5>] dev_uevent+0xc5/0x170
[<ffffffff81241dc7>] kobject_uevent_env+0x1f7/0x490
[<ffffffff81040189>] ? sub_preempt_count+0x29/0x60
[<ffffffff814cab1a>] ? _raw_spin_unlock_irqrestore+0x4a/0x90
[<ffffffff81305307>] ? devres_release_all+0x27/0x60
[<ffffffff8124206b>] kobject_uevent+0xb/0x10
[<ffffffff812fee27>] device_del+0x157/0x1b0
[<ffffffff8130377d>] platform_device_del+0x1d/0x90
[<ffffffff81303b76>] platform_device_unregister+0x16/0x30
[<ffffffffa030fffd>] regulatory_exit+0x5d/0x180 [cfg80211]
[<ffffffffa032bec3>] cfg80211_exit+0x2b/0x45 [cfg80211]
[<ffffffff8109a84c>] sys_delete_module+0x16c/0x220
[<ffffffff8108a23e>] ? trace_hardirqs_on_caller+0x7e/0x120
[<ffffffff814cba02>] system_call_fastpath+0x16/0x1b
Code: <all your base are belong to me>
RIP [<ffffffffa030df9a>] reg_device_uevent+0x1a/0x50 [cfg80211]
RSP <ffff88001c5f9d58>
CR2: ffff88001a06b5ab
---[ end trace 147c5099a411e8c0 ]---
Reported-by: Johannes Berg <johannes@sipsolutions.net>
Cc: Scott James Remnant <keybuk@google.com>
Cc: stable@vger.kernel.org
Signed-off-by: Luis R. Rodriguez <mcgrof@qca.qualcomm.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When receiving failed PLCP frames is enabled, there
won't be a rate pointer when we add the radiotap
header and thus the kernel will crash. Fix this by
not assuming the rate pointer is always valid. It's
still always valid for frames that have good PLCP
though, and that is checked & enforced.
This was broken by my
commit fc88518916
Author: Johannes Berg <johannes.berg@intel.com>
Date: Fri Jul 30 13:23:12 2010 +0200
mac80211: don't check rates on PLCP error frames
where I removed the check in this case but didn't
take into account that the rate info would be used.
Reported-by: Xiaokang Qin <xiaokang.qin@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Timers set by __set_chan_timer() should use miliseconds instead of
jiffies. Commit 942ecc9c46 updated
l2cap_set_timer() so it expects timeout to be specified in msecs
instead of jiffies. This makes timeouts unreliable when CONFIG_HZ
is not set to 1000.
Signed-off-by: Andrzej Kaczmarek <andrzej.kaczmarek@tieto.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
When comparing two items by IE, the sort order
wasn't stable, which could lead to issues in the
rbtree. Make it stable by making a missing IE
sort before a present IE.
Also sort by length first if it differs and then
by contents.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
In other modes the parameters should not be set.
Right now, mac80211 will set them, even if the
user asked for setting them on VLANs which the
driver doesn't know about, causing all kinds of
trouble.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Since the NL80211_ATTR_HT_CAPABILITY attribute is
used as a struct, it needs a minimum, not maximum
length. Enforce that properly. Not doing so could
potentially lead to reading after the buffer.
Cc: stable@vger.kernel.org
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Some buggy APs (and even P2P_GO) don't advertise their
basic rates in the association response.
In such case, use the min supported rate as the
basic rate.
Reported-by: Pontus Fuchs <pontus.fuchs@gmail.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Only AID values 1-2007 are valid, but some APs have been
found to send random bogus values, in the reported case an
AP that was sending the AID field value 0xffff, an AID of
0x3fff (16383).
There isn't much we can do but disable powersave since
there's no way it can work properly in this case.
Cc: stable@vger.kernel.org
Reported-by: Bill C Riemers <briemers@redhat.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
We need to verify whether the command is successful before allocating
the station entry to avoid extra processing. This also fixes a memory
leak on the error path.
Signed-off-by: Jouni Malinen <j@w1.fi>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
When going back on-channel, we should reconfigure
the hw iff the hardware is not already configured
to the operational channel.
Signed-off-by: Eliad Peller <eliad@wizery.com>
Cc: stable@kernel.org # 2.6.39+
Signed-off-by: John W. Linville <linville@tuxdriver.com>
The offchannel code is currently broken - we should
remain_off_channel if the work was started, and
the work's channel and channel_type are the same
as local->tmp_channel and local->tmp_channel_type.
However, if wk->chan_type and local->tmp_channel_type
coexist (e.g. have the same channel type), we won't
remain_off_channel.
This behavior was introduced by commit da2fd1f
("mac80211: Allow work items to use existing
channel type.")
Tested-by: Ben Greear <greearb@candelatech.com>
Signed-off-by: Eliad Peller <eliad@wizery.com>
Cc: stable@kernel.org # 2.6.39+
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Luis R. Rodriguez
Emmanuel Grumbach
Nikolay Martynov
Johannes Berg
Eliad Peller
Helmut Schaa
Ben Greear
John W. Linville
Andrzej Kaczmarek
Arek Lichwa
Janusz.Dziedzic@tieto.com
Jouni Malinen