linux/drivers
Larry Finger 2d838bb608 b43legacy: Fix crash on unload when firmware not available
When b43legacy is loaded without the firmware being available, a following
unload generates a kernel NULL pointer dereference BUG as follows:

[  214.330789] BUG: unable to handle kernel NULL pointer dereference at 0000004c
[  214.330997] IP: [<c104c395>] drain_workqueue+0x15/0x170
[  214.331179] *pde = 00000000
[  214.331311] Oops: 0000 [#1] SMP
[  214.331471] Modules linked in: b43legacy(-) ssb pcmcia mac80211 cfg80211 af_packet mperf arc4 ppdev sr_mod cdrom sg shpchp yenta_socket pcmcia_rsrc pci_hotplug pcmcia_core battery parport_pc parport floppy container ac button edd autofs4 ohci_hcd ehci_hcd usbcore usb_common thermal processor scsi_dh_rdac scsi_dh_hp_sw scsi_dh_emc scsi_dh_alua scsi_dh fan thermal_sys hwmon ata_generic pata_ali libata [last unloaded: cfg80211]
[  214.333421] Pid: 3639, comm: modprobe Not tainted 3.6.0-rc6-wl+ #163 Source Technology VIC 9921/ALI Based Notebook
[  214.333580] EIP: 0060:[<c104c395>] EFLAGS: 00010246 CPU: 0
[  214.333687] EIP is at drain_workqueue+0x15/0x170
[  214.333788] EAX: c162ac40 EBX: cdfb8360 ECX: 0000002a EDX: 00002a2a
[  214.333890] ESI: 00000000 EDI: 00000000 EBP: cd767e7c ESP: cd767e5c
[  214.333957]  DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068
[  214.333957] CR0: 8005003b CR2: 0000004c CR3: 0c96a000 CR4: 00000090
[  214.333957] DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000
[  214.333957] DR6: ffff0ff0 DR7: 00000400
[  214.333957] Process modprobe (pid: 3639, ti=cd766000 task=cf802e90 task.ti=cd766000)
[  214.333957] Stack:
[  214.333957]  00000292 cd767e74 c12c5e09 00000296 00000296 cdfb8360 cdfb9220 00000000
[  214.333957]  cd767e90 c104c4fd cdfb8360 cdfb9220 cd682800 cd767ea4 d0c10184 cd682800
[  214.333957]  cd767ea4 cba31064 cd767eb8 d0867908 cba31064 d087e09c cd96f034 cd767ec4
[  214.333957] Call Trace:
[  214.333957]  [<c12c5e09>] ? skb_dequeue+0x49/0x60
[  214.333957]  [<c104c4fd>] destroy_workqueue+0xd/0x150
[  214.333957]  [<d0c10184>] ieee80211_unregister_hw+0xc4/0x100 [mac80211]
[  214.333957]  [<d0867908>] b43legacy_remove+0x78/0x80 [b43legacy]
[  214.333957]  [<d083654d>] ssb_device_remove+0x1d/0x30 [ssb]
[  214.333957]  [<c126f15a>] __device_release_driver+0x5a/0xb0
[  214.333957]  [<c126fb07>] driver_detach+0x87/0x90
[  214.333957]  [<c126ef4c>] bus_remove_driver+0x6c/0xe0
[  214.333957]  [<c1270120>] driver_unregister+0x40/0x70
[  214.333957]  [<d083686b>] ssb_driver_unregister+0xb/0x10 [ssb]
[  214.333957]  [<d087c488>] b43legacy_exit+0xd/0xf [b43legacy]
[  214.333957]  [<c1089dde>] sys_delete_module+0x14e/0x2b0
[  214.333957]  [<c110a4a7>] ? vfs_write+0xf7/0x150
[  214.333957]  [<c1240050>] ? tty_write_lock+0x50/0x50
[  214.333957]  [<c110a6f8>] ? sys_write+0x38/0x70
[  214.333957]  [<c1397c55>] syscall_call+0x7/0xb
[  214.333957] Code: bc 27 00 00 00 00 a1 74 61 56 c1 55 89 e5 e8 a3 fc ff ff 5d c3 90 55 89 e5 57 56 89 c6 53 b8 40 ac 62 c1 83 ec 14 e8 bb b7 34 00 <8b> 46 4c 8d 50 01 85 c0 89 56 4c 75 03 83 0e 40 80 05 40 ac 62
[  214.333957] EIP: [<c104c395>] drain_workqueue+0x15/0x170 SS:ESP 0068:cd767e5c
[  214.333957] CR2: 000000000000004c
[  214.341110] ---[ end trace c7e90ec026d875a6 ]---Index: wireless-testing/drivers/net/wireless/b43legacy/main.c

The problem is fixed by making certain that the ucode pointer is not NULL
before deregistering the driver in mac80211.

Signed-off-by: Larry Finger <Larry.Finger@lwfinger.net>
Cc: Stable <stable@vger.kernel.org>   [v 3.3.0+]
Signed-off-by: John W. Linville <linville@tuxdriver.com>
2012-09-28 13:54:07 -04:00
..
accessibility
acpi Merge branch 'linux-next' of git://cavan.codon.org.uk/platform-drivers-x86 2012-07-30 11:54:53 -07:00
amba Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-07-27 15:14:26 -07:00
ata ata/pata_arasan: remove conditional compilation of clk code 2012-07-30 17:25:12 -07:00
atm
auxdisplay
base Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-08-01 10:26:23 -07:00
bcma bcma: change delays to follow timers-howto guide 2012-09-28 13:54:02 -04:00
block Merge branch 'for-3.6/drivers' of git://git.kernel.dk/linux-block 2012-08-01 09:06:47 -07:00
bluetooth Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/bluetooth/bluetooth-next 2012-09-24 14:39:16 -04:00
cdrom
char This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
clk clk: validate pointer in __clk_disable() 2012-07-30 17:25:13 -07:00
clocksource arm-soc: new SoC support 2012-07-23 16:31:31 -07:00
connector
cpufreq ARM: arm-soc soc updates, take 2 2012-07-30 09:45:53 -07:00
cpuidle Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-07-26 14:28:55 -07:00
crypto This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
dca
devfreq
dio
dma Merge branch 'dmaengine' of git://git.linaro.org/people/rmk/linux-arm 2012-08-01 16:41:07 -07:00
edac Merge branch 'devel' 2012-07-29 21:11:05 -03:00
eisa
extcon MFD bits for the 3.6 merge window. 2012-07-30 12:41:17 -07:00
firewire - Small fixes and optimizations. 2012-07-30 09:32:39 -07:00
firmware This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
gpio MFD bits for the 3.6 merge window. 2012-07-30 12:41:17 -07:00
gpu Merge branch 'drm-next' of git://people.freedesktop.org/~airlied/linux 2012-07-30 10:06:23 -07:00
hid Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-07-31 18:47:44 -07:00
hsi
hv This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
hwmon Merge branch 'hwmon-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jdelvare/staging 2012-07-30 10:10:26 -07:00
hwspinlock
i2c This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
ide
idle Merge branch 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux 2012-07-26 14:28:55 -07:00
ieee802154
iio
infiniband Merge branches 'cma', 'ipoib', 'ocrdma' and 'qib' into for-next 2012-07-30 07:47:27 -07:00
input This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
iommu IOMMU Updates for Linux v3.6-rc1 2012-07-24 16:24:11 -07:00
isdn mISDN: Bugfix only few bytes are transfered on a connection 2012-07-29 23:18:30 -07:00
leds leds-lp8788: forgotten unlock at lp8788_led_work 2012-07-27 08:16:07 +08:00
lguest
macintosh
md Merge branch 'for-3.6/drivers' of git://git.kernel.dk/linux-block 2012-08-01 09:06:47 -07:00
media Merge branch 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media 2012-07-31 18:47:44 -07:00
memory
memstick
message drivers/message/i2o/i2o_config.c: bound allocation 2012-07-30 17:25:17 -07:00
mfd This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
misc Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-30 17:25:34 -07:00
mmc Merge branch 'dmaengine' of git://git.linaro.org/people/rmk/linux-arm 2012-08-01 16:41:07 -07:00
mtd Merge branch 'dmaengine' of git://git.linaro.org/people/rmk/linux-arm 2012-08-01 16:41:07 -07:00
net b43legacy: Fix crash on unload when firmware not available 2012-09-28 13:54:07 -04:00
nfc NFC: Fix missing mutex unlock in pn533_send_cmd_frame_async 2012-09-27 10:47:48 +02:00
nubus
of Devicetree updates for 3.6 2012-07-24 14:07:22 -07:00
oprofile
parisc PCI changes for the 3.6 merge window: 2012-07-24 16:17:07 -07:00
parport
pci PCI changes for the 3.6 merge window: 2012-07-24 16:17:07 -07:00
pcmcia Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-07-27 15:14:26 -07:00
pinctrl Pin control changes for v3.6: 2012-07-24 14:05:46 -07:00
platform Merge branch 'linux-next' of git://cavan.codon.org.uk/platform-drivers-x86 2012-07-30 11:54:53 -07:00
pnp
power This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
pps pps: return PTR_ERR on error in device_create 2012-07-30 17:25:21 -07:00
ps3
ptp
pwm pwm: pwm-tiehrpwm: PWM driver support for EHRPWM 2012-07-26 07:45:20 +02:00
rapidio
regulator regulator: Fix an s5m8767 build failure 2012-07-31 00:51:09 +02:00
remoteproc A batch of remoteproc patches for 3.6: 2012-07-26 16:19:08 -07:00
rpmsg A batch of remoteproc patches for 3.6: 2012-07-26 16:19:08 -07:00
rtc Merge branch 'akpm' (Andrew's patch-bomb) 2012-07-31 19:25:39 -07:00
s390 Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2012-07-26 18:09:01 -07:00
sbus
scsi Merge branch 'for-3.6/core' of git://git.kernel.dk/linux-block 2012-08-01 09:02:41 -07:00
sfi
sh Merge branch 'common/pinctrl' into sh-latest 2012-07-20 16:42:59 +09:00
sn
spi Merge branch 'dmaengine' of git://git.linaro.org/people/rmk/linux-arm 2012-08-01 16:41:07 -07:00
ssb ssb: check for flash presentence 2012-08-10 15:27:02 -04:00
staging Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/linville/wireless 2012-09-07 15:07:55 -04:00
target Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-08-01 10:26:23 -07:00
tc
thermal The tag contains just a few battery-related changes for v3.6. It's is 2012-07-31 18:08:25 -07:00
tty This patch series contains a major revamp of how we collect entropy 2012-07-31 19:07:42 -07:00
uio
usb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2012-08-01 10:26:23 -07:00
uwb
vfio vfio: Add PCI device driver 2012-07-31 08:16:24 -06:00
vhost vhost: make vhost work queue visible 2012-07-22 01:22:23 +03:00
video fbdev updates for 3.6 2012-08-01 10:45:12 -07:00
virt
virtio [SCSI] virtio-scsi: Add vdrv->scan for post VIRTIO_CONFIG_S_DRIVER_OK LUN scanning 2012-07-20 08:59:03 +01:00
vlynq
vme VME: Prevent D16 cycles being split into 8-bit blocks 2012-07-19 15:39:39 -07:00
w1 Driver core merge for 3.6-rc1 2012-07-26 11:25:33 -07:00
watchdog Merge branch 'for-linus' of git://git.linaro.org/people/rmk/linux-arm 2012-07-27 15:14:26 -07:00
xen PCI changes for the 3.6 merge window: 2012-07-24 16:17:07 -07:00
zorro
Kconfig vfio: VFIO core 2012-07-31 08:16:22 -06:00
Makefile vfio: VFIO core 2012-07-31 08:16:22 -06:00