Commit Graph

109 Commits

Author SHA1 Message Date
Luis R. Rodriguez
724ad42667 cfg80211: fix syntax error on user regulatory hints
commit e12822e1d3 upstream.

This fixes a syntax error when setting up the user regulatory
hint. This change yields the same exact binary object though
so it ends up just being a syntax typo fix, fortunately.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
2010-01-18 10:19:45 -08:00
Thadeu Lima de Souza Cascardo
1fe90b033e trivial: remove duplicate "different" from comment
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-14 09:14:02 -04:00
Pat Erley
d5b96a6f39 mac80211: remove max_bandwidth
This removes the max_bandwidth attribute.  It is only ever
written to, and is duplicated by max_bandwidth_khz in the
regulatory code.

Signed-off-by: Pat Erley <pat-lkml@erley.org>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-14 09:13:53 -04:00
David S. Miller
aa11d958d1 Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	arch/microblaze/include/asm/socket.h
2009-08-12 17:44:53 -07:00
Luis R. Rodriguez
8b19e6ca3b cfg80211: enable country IE support to all cfg80211 drivers
Since the bss is always set now once we are connected, if the
bss has its own information element we refer to it and pass that
instead of relying on mac80211's parsing.

Now all cfg80211 drivers get country IE support, automatically and
we reduce the call overhead that we had on mac80211 which called this
upon every beacon and instead now call this only upon a successfull
connection by a STA on cfg80211.

Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:44:19 -04:00
Luis R. Rodriguez
abc7381bcc cfg80211: decouple regulatory variables from cfg80211_mutex
We change regulatory code to be protected by its own regulatory
mutex and alleviate cfg80211_mutex to only be used to protect
cfg80211_rdev_list, the registered device list.

By doing this we will be able to work on regulatory core components
without having to have hog up the cfg80211_mutex. An example here is
we no longer need to use the cfg80211_mutex during driver specific
wiphy_apply_custom_regulatory(). We also no longer need it for the
the country IE regulatory hint; by doing so we end up curing this
new lockdep warning:

=======================================================
[ INFO: possible circular locking dependency detected ]
2.6.31-rc4-wl #12
-------------------------------------------------------
phy1/1709 is trying to acquire lock:
 (cfg80211_mutex){+.+.+.}, at: [<ffffffffa00af852>] regulatory_hint_11d+0x32/0x3f0 [cfg80211]

but task is already holding lock:
 (&ifmgd->mtx){+.+.+.}, at: [<ffffffffa0144228>] ieee80211_sta_work+0x108/0x10f0 [mac80211]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #3 (&ifmgd->mtx){+.+.+.}:
       [<ffffffff810857b6>] __lock_acquire+0xd76/0x12b0
       [<ffffffff81085dd3>] lock_acquire+0xe3/0x120
       [<ffffffff814eeae4>] mutex_lock_nested+0x44/0x350
       [<ffffffffa0141bb8>] ieee80211_mgd_auth+0x108/0x1f0 [mac80211]
       [<ffffffffa0148563>] ieee80211_auth+0x13/0x20 [mac80211]
       [<ffffffffa00bc3a1>] __cfg80211_mlme_auth+0x1b1/0x2a0 [cfg80211]
       [<ffffffffa00bc516>] cfg80211_mlme_auth+0x86/0xc0 [cfg80211]
       [<ffffffffa00b368d>] nl80211_authenticate+0x21d/0x230 [cfg80211]
       [<ffffffff81416ba6>] genl_rcv_msg+0x1b6/0x1f0
       [<ffffffff81415c39>] netlink_rcv_skb+0x89/0xb0
       [<ffffffff814169d9>] genl_rcv+0x29/0x40
       [<ffffffff8141591d>] netlink_unicast+0x29d/0x2b0
       [<ffffffff81416514>] netlink_sendmsg+0x214/0x300
       [<ffffffff813e4407>] sock_sendmsg+0x107/0x130
       [<ffffffff813e45b9>] sys_sendmsg+0x189/0x320
       [<ffffffff81011f82>] system_call_fastpath+0x16/0x1b
       [<ffffffffffffffff>] 0xffffffffffffffff

-> #2 (&wdev->mtx){+.+.+.}:
       [<ffffffff810857b6>] __lock_acquire+0xd76/0x12b0
       [<ffffffff81085dd3>] lock_acquire+0xe3/0x120
       [<ffffffff814eeae4>] mutex_lock_nested+0x44/0x350
       [<ffffffffa00ab304>] cfg80211_netdev_notifier_call+0x1a4/0x390 [cfg80211]
       [<ffffffff814f3dff>] notifier_call_chain+0x3f/0x80
       [<ffffffff81075a91>] raw_notifier_call_chain+0x11/0x20
       [<ffffffff813f665a>] dev_open+0x10a/0x120
       [<ffffffff813f59bd>] dev_change_flags+0x9d/0x1e0
       [<ffffffff8144eb6e>] devinet_ioctl+0x6fe/0x760
       [<ffffffff81450204>] inet_ioctl+0x94/0xc0
       [<ffffffff813e25fa>] sock_ioctl+0x6a/0x290
       [<ffffffff8111e911>] vfs_ioctl+0x31/0xa0
       [<ffffffff8111ea9a>] do_vfs_ioctl+0x8a/0x5c0
       [<ffffffff8111f069>] sys_ioctl+0x99/0xa0
       [<ffffffff81011f82>] system_call_fastpath+0x16/0x1b
       [<ffffffffffffffff>] 0xffffffffffffffff

-> #1 (&rdev->mtx){+.+.+.}:
       [<ffffffff810857b6>] __lock_acquire+0xd76/0x12b0
       [<ffffffff81085dd3>] lock_acquire+0xe3/0x120
       [<ffffffff814eeae4>] mutex_lock_nested+0x44/0x350
       [<ffffffffa00ac4d0>] cfg80211_get_dev_from_ifindex+0x60/0x90 [cfg80211]
       [<ffffffffa00b21ff>] get_rdev_dev_by_info_ifindex+0x6f/0xa0 [cfg80211]
       [<ffffffffa00b51eb>] nl80211_set_interface+0x3b/0x260 [cfg80211]
       [<ffffffff81416ba6>] genl_rcv_msg+0x1b6/0x1f0
       [<ffffffff81415c39>] netlink_rcv_skb+0x89/0xb0
       [<ffffffff814169d9>] genl_rcv+0x29/0x40
       [<ffffffff8141591d>] netlink_unicast+0x29d/0x2b0
       [<ffffffff81416514>] netlink_sendmsg+0x214/0x300
       [<ffffffff813e4407>] sock_sendmsg+0x107/0x130
       [<ffffffff813e45b9>] sys_sendmsg+0x189/0x320
       [<ffffffff81011f82>] system_call_fastpath+0x16/0x1b
       [<ffffffffffffffff>] 0xffffffffffffffff

other info that might help us debug this:

3 locks held by phy1/1709:
 #0:  ((wiphy_name(local->hw.wiphy))){+.+.+.}, at: [<ffffffff8106b45d>] worker_thread+0x19d/0x340
 #1:  (&ifmgd->work){+.+.+.}, at: [<ffffffff8106b45d>] worker_thread+0x19d/0x340
 #2:  (&ifmgd->mtx){+.+.+.}, at: [<ffffffffa0144228>] ieee80211_sta_work+0x108/0x10f0 [mac80211]

Reported-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:44:18 -04:00
Luis R. Rodriguez
4b44c8bc4d cfg80211: do not iterate over rdev list on country IE hint
Simplify the country IE hint code by just bailing out if
a previous country IE has been issued. We currently just trust
the first AP we connect to on any card. The idea was to perform
conflict resolution within this routine but since we can no longer
iterate over the registered device list here we leave conflict
resolution to be dealt with at a later time on the workqueue.

This code has no functional changes other than saving us an
interation over the registered device list when a second card
is connected, or you unplug and connect the same one, and a
country IE is received. This would have been done upon every
beacon received.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:44:18 -04:00
Luis R. Rodriguez
9828b0170e cfg80211: use goto out on country IE reg hint failure
This has no functional changes.

Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-04 16:44:18 -04:00
Luis R. Rodriguez
371842448c cfg80211: fix regression on beacon world roaming feature
A regression was added through patch a4ed90d6:

"cfg80211: respect API on orig_flags on channel for beacon hint"

We did indeed respect _orig flags but the intention was not clearly
stated in the commit log. This patch fixes firmware issues picked
up by iwlwifi when we lift passive scan of beaconing restrictions
on channels its EEPROM has been configured to always enable.

By doing so though we also disallowed beacon hints on devices
registering their wiphy with custom world regulatory domains
enabled, this happens to be currently ath5k, ath9k and ar9170.
The passive scan and beacon restrictions on those devices would
never be lifted even if we did find a beacon and the hardware did
support such enhancements when world roaming.

Since Johannes indicates iwlwifi firmware cannot be changed to
allow beacon hinting we set up a flag now to specifically allow
drivers to disable beacon hints for devices which cannot use them.

We enable the flag on iwlwifi to disable beacon hints and by default
enable it for all other drivers. It should be noted beacon hints lift
passive scan flags and beacon restrictions when we receive a beacon from
an AP on any 5 GHz non-DFS channels, and channels 12-14 on the 2.4 GHz
band. We don't bother with channels 1-11 as those channels are allowed
world wide.

This should fix world roaming for ath5k, ath9k and ar9170, thereby
improving scan time when we receive the first beacon from any AP,
and also enabling beaconing operation (AP/IBSS/Mesh) on cards which
would otherwise not be allowed to do so. Drivers not using custom
regulatory stuff (wiphy_apply_custom_regulatory()) were not affected
by this as the orig_flags for the channels would have been cleared
upon wiphy registration.

I tested this with a world roaming ath5k card.

Cc: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-08-03 16:31:21 -04:00
Luis R. Rodriguez
ae9e4b0d1a cfg80211: treat ieee80211_regdom hints as user hints
We were treating ieee80211_regdom module parameter hints
as core hints, this means we were not letting the user help
compliance further when using the module parameter. It also
meant that users with a device with a custom regulatory
domain set (wiphy->custom_regulatory) using this module
parameter were being stuck to the original default core
static regualtory domain. We fix this by using the static
cfg80211_regdomain alpha2 as the core hint and treating the
module parameter separately.

All iwlwifi and ath5k/ath9k/ar9170 devices which world roam
set the wiphy->custom_regulatory. This change allows users
using this module parameter to have it trated as a a proper
user hint and not have it ignored.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Acked-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-24 15:05:19 -04:00
Johannes Berg
79c97e97ae cfg80211: clean up naming once and for all
We've named the registered devices 'drv' sometimes,
thinking of "driver", which is not what it is, it's
the internal representation of a wiphy, i.e. a
device. Let's clean up the naming once and and use
'rdev' aka 'registered device' everywhere.

Signed-off-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-07-10 15:02:33 -04:00
Luis R. Rodriguez
558f6d3229 cfg80211: fix for duplicate response for driver reg request
As Pavel puts userspace can be stupid and should not
cause kernel crashes. In this case Pavel was able to
find a crash here but unable to reproduce. Either way
lets deal with this.

This should fix:

------------[ cut here ]------------
kernel BUG at /home/proski/src/linux-2.6/net/wireless/reg.c:2132!
Oops: Exception in kernel mode, sig: 5 [#1]
PowerMac
Modules linked in: ath5k ath [last unloaded: scsi_wait_scan]
NIP: c02f3eac LR: c02f3d08 CTR: 00000000
REGS: ef107aa0 TRAP: 0700   Not tainted  (2.6.30-rc8-wl)
MSR: 00029032 <EE,ME,CE,IR,DR>  CR: 88002442  XER: 20000000
TASK = ef84acb0[834] 'crda' THREAD: ef106000
GPR00: ef953840 ef107b50 ef84acb0 ef1380bc 00000006 c035a5c8 ef107b90 c035a5c8
GPR08: 00080005 efb68980 c0445628 ef130004 28002422 10019ce0 10012d3c 00000001
GPR16: 1070b2ac 00000005 48023558 1070b380 4802304c 00000000 ef107ddc c035a5c8
GPR24: ef107b78 c0443350 ef8bcb00 00000005 ef138080 c04a6a70 c04a0000 ef8bcb00
NIP [c02f3eac] set_regdom+0x4c4/0x4ec
LR [c02f3d08] set_regdom+0x320/0x4ec
Call Trace:
[ef107b50] [c02f3d08] set_regdom+0x320/0x4ec (unreliable)
[ef107b70] [c02f9d10] nl80211_set_reg+0x140/0x2d0
[ef107bc0] [c02aa2b8] genl_rcv_msg+0x204/0x228
[ef107c10] [c02a97cc] netlink_rcv_skb+0xe8/0x10c
[ef107c30] [c02aa094] genl_rcv+0x3c/0x5c
[ef107c40] [c02a9050] netlink_unicast+0x308/0x36c
[ef107c80] [c02a92bc] netlink_sendmsg+0x208/0x2f0
[ef107cd0] [c0282048] sock_sendmsg+0xac/0xe4
[ef107db0] [c02822b4] sys_sendmsg+0x234/0x2d8
[ef107f00] [c0283a88] sys_socketcall+0x108/0x258
[ef107f40] [c0012790] ret_from_syscall+0x0/0x38

Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-06-10 13:28:37 -04:00
Luis R. Rodriguez
729e9c7663 cfg80211: fix for duplicate userspace replies
This fixes an incorrect assumption (BUG_ON) made in
cfg80211 when handling country IE regulatory requests.
The assumption was that we won't try to call_crda()
twice for the same event and therefore we will not
recieve two replies through nl80211 for the regulatory
request. As it turns out it is true we don't call_crda()
twice for the same event, however, kobject_uevent_env()
*might* send the udev event twice and/or userspace can
simply process the udev event twice. We remove the BUG_ON()
and simply ignore the duplicate request.

For details refer to this thread:

http://marc.info/?l=linux-wireless&m=124149987921337&w=2

Cc: stable@kernel.org
Reported-by: Maxim Levitsky <maximlevitsky@gmail.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-06-03 14:05:12 -04:00
David S. Miller
c649c0e31d Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	drivers/net/wireless/ath/ath5k/phy.c
	drivers/net/wireless/iwlwifi/iwl-agn.c
	drivers/net/wireless/iwlwifi/iwl3945-base.c
2009-05-25 01:42:21 -07:00
Luis R. Rodriguez
bbcf3f0277 cfg80211: warn when wiphy_apply_custom_regulatory() does nothing
Device drivers using wiphy_apply_custom_regulatory() want some
regulatory settings applied to their wiphy, if no bands were
configured on the wiphy then something went wrong.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-20 14:46:37 -04:00
Luis R. Rodriguez
61405e9778 cfg80211: fix in nl80211_set_reg()
There is a race on access to last_request and its alpha2
through reg_is_valid_request() and us possibly processing
first another regulatory request on another CPU. We avoid
this improbably race by locking with the cfg80211_mutex as
we should have done in the first place. While at it add
the assert on locking on reg_is_valid_request().

Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-20 14:46:32 -04:00
Luis R. Rodriguez
689da1b3b8 wireless: rename IEEE80211_CHAN_NO_FAT_* to HT40-/+
This is more consistent with our nl80211 naming convention
for HT40-/+.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-20 14:46:22 -04:00
Luis R. Rodriguez
038659e7c6 cfg80211: Process regulatory max bandwidth checks for HT40
We are not correctly listening to the regulatory max bandwidth
settings. To actually make use of it we need to redesign things
a bit. This patch does the work for that. We do this to so we
can obey to regulatory rules accordingly for use of HT40.

We end up dealing with HT40 by having two passes for each channel.

The first check will see if a 20 MHz channel fits into the channel's
center freq on a given frequency range. We check for a 20 MHz
banwidth channel as that is the maximum an individual channel
will use, at least for now. The first pass will go ahead and
check if the regulatory rule for that given center of frequency
allows 40 MHz bandwidths and we use this to determine whether
or not the channel supports HT40 or not. So to support HT40 you'll
need at a regulatory rule that allows you to use 40 MHz channels
but you're channel must also be enabled and support 20 MHz by itself.

The second pass is done after we do the regulatory checks over
an device's supported channel list. On each channel we'll check
if the control channel and the extension both:

 o exist
 o are enabled
 o regulatory allows 40 MHz bandwidth on its frequency range

This work allows allows us to idependently check for HT40- and
HT40+.

Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-20 14:46:22 -04:00
Luis R. Rodriguez
5078b2e32a cfg80211: fix race between core hint and driver's custom apply
Its possible for cfg80211 to have scheduled the work and for
the global workqueue to not have kicked in prior to a cfg80211
driver's regulatory hint or wiphy_apply_custom_regulatory().

Although this is very unlikely its possible and should fix
this race. When this race would happen you are expected to have
hit a null pointer dereference panic.

Cc: stable@kernel.org
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Tested-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-20 14:29:54 -04:00
David S. Miller
a8679be207 Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless-next-2.6 2009-05-08 12:46:17 -07:00
David S. Miller
22f6dacdfc Merge branch 'master' of master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6
Conflicts:
	include/net/tcp.h
2009-05-08 02:48:30 -07:00
Chris Wright
0ef9ccdd9e cfg80211: remove superfluous !last_request check in reg_device_remove()
Commit 0ad8acaf "cfg80211: fix NULL pointer deference in
reg_device_remove()" added a check that last_request is non-NULL,
rendering the 2nd check superfluous.  While there, rearrange the code a
bit so it's a little more straight forward.

Signed-off-by: Chris Wright <chrisw@sous-sol.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-06 15:14:40 -04:00
Luis R. Rodriguez
30a548c727 cfg80211: fix comment on regulatory hint processing
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-04 16:22:14 -04:00
Luis R. Rodriguez
b1ed8ddd21 cfg80211: fix bug while trying to process beacon hints on init
During initialization we would not have received any beacons
so skip processing reg beacon hints, also adds a check to
reg_is_world_roaming() for last_request before accessing its
fields.

This should fix this:

BUG: unable to handle kernel NULL pointer dereference at

IP: [<e0171332>] wiphy_update_regulatory+0x20f/0x295

*pdpt = 0000000008bf1001 *pde = 0000000000000000
Oops: 0000 [#1]
last sysfs file: /sys/class/backlight/eeepc/brightness
Modules linked in: ath5k(+) mac80211 led_class cfg80211
go_bit cfbcopyarea cfbimgblt cfbfillrect ipv6
ydev usual_tables(P) snd_hda_codec_realtek snd_hda_intel
nd_hwdep uhci_hcd snd_pcm_oss snd_mixer_oss i2c_i801
e serio_raw i2c_core pcspkr atl2 snd_pcm intel_agp
re agpgart eeepc_laptop snd_page_alloc ac video backlight
rfkill button processor evdev thermal fan ata_generic

Pid: 2909, comm: modprobe Tainted: Pc #112) 701
EIP: 0060:[<e0171332>] EFLAGS: 00010246 CPU: 0
EIP is at wiphy_update_regulatory+0x20f/0x295 [cfg80211]
EAX: 00000000 EBX: c5da0000 ECX: 00000000 EDX: c5da0060
ESI: 0000001a EDI: c5da0060 EBP: df3bdd70 ESP: df3bdd40
 DS: 007b ES: 007b FS: 0000 GS: 0033 SS: 0068
Process modprobe (pid: 2909, ti=df3bc000 task=c5d030000)
Stack:
 df3bdd90 c5da0060 c04277e0 00000001 00000044 c04277e402
 00000002 c5da0000 0000001a c5da0060 df3bdda8 e01706a2 02
 00000282 000080d0 00000068 c5d53500 00000080 0000028240
Call Trace:
 [<e01706a2>] ? wiphy_register+0x122/0x1b7 [cfg80211]
 [<e0328e02>] ? ieee80211_register_hw+0xd8/0x346
 [<e06a7c9f>] ? ath5k_hw_set_bssid_mask+0x71/0x78 [ath5k]
 [<e06b0c52>] ? ath5k_pci_probe+0xa5c/0xd0a [ath5k]
 [<c01a6037>] ? sysfs_find_dirent+0x16/0x27
 [<c01fec95>] ? local_pci_probe+0xe/0x10
 [<c01ff526>] ? pci_device_probe+0x48/0x66
 [<c024c9fd>] ? driver_probe_device+0x7f/0xf2
 [<c024cab3>] ? __driver_attach+0x43/0x5f
 [<c024c0af>] ? bus_for_each_dev+0x39/0x5a
 [<c024c8d0>] ? driver_attach+0x14/0x16
 [<c024ca70>] ? __driver_attach+0x0/0x5f
 [<c024c5b3>] ? bus_add_driver+0xd7/0x1e7
 [<c024ccb9>] ? driver_register+0x7b/0xd7
 [<c01ff827>] ? __pci_register_driver+0x32/0x85
 [<e00a8018>] ? init_ath5k_pci+0x18/0x30 [ath5k]
 [<c0101131>] ? _stext+0x49/0x10b
 [<e00a8000>] ? init_ath5k_pci+0x0/0x30 [ath5k]
 [<c012f452>] ? __blocking_notifier_call_chain+0x40/0x4c
 [<c013a714>] ? sys_init_module+0x87/0x18b
 [<c0102804>] ? sysenter_do_call+0x12/0x22
Code: b8 da 17 e0 83 c0 04 e8 92 f9 ff ff 84 c0 75 2a 8b
85 c0 74 0c 83 c0 04 e8 7c f9 ff ff 84 c0 75 14 a1 bc da
4 03 74 66 8b 4d d4 80 79 08 00 74 5d a1 e0 d2 17 e0 48
EIP: [<e0171332>] wiphy_update_regulatory+0x20f/0x295
SP 0068:df3bdd40
CR2: 0000000000000004
---[ end trace 830f2dd2a95fd1a8 ]---

This issue is hard to reproduce, but it was noticed and discussed on
this thread:

http://marc.info/?t=123938022700005&r=1&w=2

Cc: stable@kernel.org
Reported-by: Alan Jenkins <alan-jenkins@tuffmail.co.uk>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-04 16:22:13 -04:00
Luis R. Rodriguez
ac46d48e00 cfg80211: fix race condition with wiphy_apply_custom_regulatory()
We forgot to lock using the cfg80211_mutex in
wiphy_apply_custom_regulatory(). Without the lock
there is possible race between processing a reply from CRDA
and a driver calling wiphy_apply_custom_regulatory(). During
the processing of the reply from CRDA we free last_request and
wiphy_apply_custom_regulatory() eventually accesses an
element from last_request in the through freq_reg_info_regd().

This is very difficult to reproduce (I haven't), it takes us
3 hours and you need to be banging hard, but the race is obvious
by looking at the code.

This should only affect those who use this caller, which currently
is ath5k, ath9k, and ar9170.

EIP: 0060:[<f8ebec50>] EFLAGS: 00210282 CPU: 1
EIP is at freq_reg_info_regd+0x24/0x121 [cfg80211]
EAX: 00000000 EBX: f7ca0060 ECX: f5183d94 EDX: 0024cde0
ESI: f8f56edc EDI: 00000000 EBP: 00000000 ESP: f5183d44
DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
Process modprobe (pid: 14617, ti=f5182000 task=f3934d10 task.ti=f5182000)
Stack: c0505300 f7ca0ab4 f5183d94 0024cde0 f8f403a6 f8f63160 f7ca0060 00000000
00000000 f8ebedf8 f5183d90 f8f56edc 00000000 00000004 00000f40 f8f56edc
f7ca0060 f7ca1234 00000000 00000000 00000000 f7ca14f0 f7ca0ab4 f7ca1289
Call Trace:
[<f8ebedf8>] wiphy_apply_custom_regulatory+0x8f/0x122 [cfg80211]
[<f8f3f798>] ath_attach+0x707/0x9e6 [ath9k]
[<f8f45e46>] ath_pci_probe+0x18d/0x29a [ath9k]
[<c023c7ba>] pci_device_probe+0xa3/0xe4
[<c02a860b>] really_probe+0xd7/0x1de
[<c02a87e7>] __driver_attach+0x37/0x55
[<c02a7eed>] bus_for_each_dev+0x31/0x57
[<c02a83bd>] driver_attach+0x16/0x18
[<c02a78e6>] bus_add_driver+0xec/0x21b
[<c02a8959>] driver_register+0x85/0xe2
[<c023c9bb>] __pci_register_driver+0x3c/0x69
[<f8e93043>] ath9k_init+0x43/0x68 [ath9k]
[<c010112b>] _stext+0x3b/0x116
[<c014a872>] sys_init_module+0x8a/0x19e
[<c01049ad>] sysenter_do_call+0x12/0x21
[<ffffe430>] 0xffffe430
=======================
Code: 0f 94 c0 c3 31 c0 c3 55 57 56 53 89 c3 83 ec 14 8b 74 24 2c 89 54 24 0c 89 4c 24 08 85 f6 75
06 8b 35 c8 bb ec f8 a1 cc bb ec f8 <8b> 40 04 83 f8 03 74 3a 48 74 37 8b 43 28 85 c0 74 30 89 c6
8b
EIP: [<f8ebec50>] freq_reg_info_regd+0x24/0x121 [cfg80211] SS:ESP 0068:f5183d44

Cc: stable@kernel.org
Reported-by: Nataraj Sadasivam <Nataraj.Sadasivam@Atheros.com>
Reported-by: Vivek Natarajan <Vivek.Natarajan@Atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2009-05-04 16:22:12 -04:00