Johan Hovold c1a658c944 Bluetooth: hci_core: fix NULL-pointer dereference at unregister ... commit 9432496206 upstream. Make sure hci_dev_open returns immediately if hci_dev_unregister has been called. This fixes a race between hci_dev_open and hci_dev_unregister which can lead to a NULL-pointer dereference. Bug is 100% reproducible using hciattach and a disconnected serial port: 0. # hciattach -n /dev/ttyO1 any noflow 1. hci_dev_open called from hci_power_on grabs req lock 2. hci_init_req executes but device fails to initialise (times out eventually) 3. hci_dev_open is called from hci_sock_ioctl and sleeps on req lock 4. hci_uart_tty_close calls hci_dev_unregister and sleeps on req lock in hci_dev_do_close 5. hci_dev_open (1) releases req lock 6. hci_dev_do_close grabs req lock and returns as device is not up 7. hci_dev_unregister sleeps in destroy_workqueue 8. hci_dev_open (3) grabs req lock, calls hci_init_req and eventually sleeps 9. hci_dev_unregister finishes, while hci_dev_open is still running... [ 79.627136] INFO: trying to register non-static key. [ 79.632354] the code is fine but needs lockdep annotation. [ 79.638122] turning off the locking correctness validator. [ 79.643920] [<c00188bc>] (unwind_backtrace+0x0/0xf8) from [<c00729c4>] (__lock_acquire+0x1590/0x1ab0) [ 79.653594] [<c00729c4>] (__lock_acquire+0x1590/0x1ab0) from [<c00733f8>] (lock_acquire+0x9c/0x128) [ 79.663085] [<c00733f8>] (lock_acquire+0x9c/0x128) from [<c0040a88>] (run_timer_softirq+0x150/0x3ac) [ 79.672668] [<c0040a88>] (run_timer_softirq+0x150/0x3ac) from [<c003a3b8>] (__do_softirq+0xd4/0x22c) [ 79.682281] [<c003a3b8>] (__do_softirq+0xd4/0x22c) from [<c003a924>] (irq_exit+0x8c/0x94) [ 79.690856] [<c003a924>] (irq_exit+0x8c/0x94) from [<c0013a50>] (handle_IRQ+0x34/0x84) [ 79.699157] [<c0013a50>] (handle_IRQ+0x34/0x84) from [<c0008530>] (omap3_intc_handle_irq+0x48/0x4c) [ 79.708648] [<c0008530>] (omap3_intc_handle_irq+0x48/0x4c) from [<c037499c>] (__irq_usr+0x3c/0x60) [ 79.718048] Exception stack(0xcf281fb0 to 0xcf281ff8) [ 79.723358] 1fa0: 0001e6a0 be8dab00 0001e698 00036698 [ 79.731933] 1fc0: 0002df98 0002df38 0000001f 00000000 b6f234d0 00000000 00000004 00000000 [ 79.740509] 1fe0: 0001e6f8 be8d6aa0 be8dac50 0000aab8 80000010 ffffffff [ 79.747497] Unable to handle kernel NULL pointer dereference at virtual address 00000000 [ 79.756011] pgd = cf3b4000 [ 79.758850] [00000000] *pgd=8f0c7831, *pte=00000000, *ppte=00000000 [ 79.765502] Internal error: Oops: 80000007 [#1] [ 79.770294] Modules linked in: [ 79.773529] CPU: 0 Tainted: G W (3.3.0-rc6-00002-gb5d5c87 #421) [ 79.781066] PC is at 0x0 [ 79.783721] LR is at run_timer_softirq+0x16c/0x3ac [ 79.788787] pc : [<00000000>] lr : [<c0040aa4>] psr: 60000113 [ 79.788787] sp : cf281ee0 ip : 00000000 fp : cf280000 [ 79.800903] r10: 00000004 r9 : 00000100 r8 : b6f234d0 [ 79.806427] r7 : c0519c28 r6 : cf093488 r5 : c0561a00 r4 : 00000000 [ 79.813323] r3 : 00000000 r2 : c054eee0 r1 : 00000001 r0 : 00000000 [ 79.820190] Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment user [ 79.827728] Control: 10c5387d Table: 8f3b4019 DAC: 00000015 [ 79.833801] Process gpsd (pid: 1265, stack limit = 0xcf2802e8) [ 79.839965] Stack: (0xcf281ee0 to 0xcf282000) [ 79.844573] 1ee0: 00000002 00000000 c0040a24 00000000 00000002 cf281f08 00200200 00000000 [ 79.853210] 1f00: 00000000 cf281f18 cf281f08 00000000 00000000 00000000 cf281f18 cf281f18 [ 79.861816] 1f20: 00000000 00000001 c056184c 00000000 00000001 b6f234d0 c0561848 00000004 [ 79.870452] 1f40: cf280000 c003a3b8 c051e79c 00000001 00000000 00000100 3fa9e7b8 0000000a [ 79.879089] 1f60: 00000025 cf280000 00000025 00000000 00000000 b6f234d0 00000000 00000004 [ 79.887756] 1f80: 00000000 c003a924 c053ad38 c0013a50 fa200000 cf281fb0 ffffffff c0008530 [ 79.896362] 1fa0: 0001e6a0 0000aab8 80000010 c037499c 0001e6a0 be8dab00 0001e698 00036698 [ 79.904998] 1fc0: 0002df98 0002df38 0000001f 00000000 b6f234d0 00000000 00000004 00000000 [ 79.913665] 1fe0: 0001e6f8 be8d6aa0 be8dac50 0000aab8 80000010 ffffffff 00fbf700 04ffff00 [ 79.922302] [<c0040aa4>] (run_timer_softirq+0x16c/0x3ac) from [<c003a3b8>] (__do_softirq+0xd4/0x22c) [ 79.931945] [<c003a3b8>] (__do_softirq+0xd4/0x22c) from [<c003a924>] (irq_exit+0x8c/0x94) [ 79.940582] [<c003a924>] (irq_exit+0x8c/0x94) from [<c0013a50>] (handle_IRQ+0x34/0x84) [ 79.948913] [<c0013a50>] (handle_IRQ+0x34/0x84) from [<c0008530>] (omap3_intc_handle_irq+0x48/0x4c) [ 79.958404] [<c0008530>] (omap3_intc_handle_irq+0x48/0x4c) from [<c037499c>] (__irq_usr+0x3c/0x60) [ 79.967773] Exception stack(0xcf281fb0 to 0xcf281ff8) [ 79.973083] 1fa0: 0001e6a0 be8dab00 0001e698 00036698 [ 79.981658] 1fc0: 0002df98 0002df38 0000001f 00000000 b6f234d0 00000000 00000004 00000000 [ 79.990234] 1fe0: 0001e6f8 be8d6aa0 be8dac50 0000aab8 80000010 ffffffff [ 79.997161] Code: bad PC value [ 80.000396] ---[ end trace 6f6739840475f9ee ]--- [ 80.005279] Kernel panic - not syncing: Fatal exception in interrupt Signed-off-by: Johan Hovold <jhovold@gmail.com> Acked-by: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: Johan Hedberg <johan.hedberg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2012-04-22 16:21:42 -07:00
..
acpi	ACPI: Store SRAT table revision	2012-01-25 17:24:57 -08:00
asm-generic	compat: use sys_sendfile64() implementation for sendfile syscall	2012-04-02 09:27:21 -07:00
crypto
drm	drm: Fix authentication kernel crash	2012-02-03 09:18:52 -08:00
keys	libceph: Create a new key type "ceph".	2011-03-29 12:11:24 -07:00
linux	sched/x86: Fix overflow in cyc2ns_offset	2012-04-13 08:14:08 -07:00
math-emu
media	[media] tuner-core/v4l2-subdev: document that the type field has to be filled in	2011-07-07 15:04:23 -03:00
mtd	UBI: fix minor stylistic issues	2011-04-14 11:34:41 +03:00
net	Bluetooth: hci_core: fix NULL-pointer dereference at unregister	2012-04-22 16:21:42 -07:00
pcmcia	pcmcia: Make declaration and uses of struct pcmcia_device_id const	2011-05-06 07:46:15 +02:00
rdma	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband	2011-05-26 12:13:57 -07:00
rxrpc	Fix common misspellings	2011-03-31 11:26:23 -03:00
scsi	[SCSI] libsas: Add option for SATA soft reset	2011-05-26 22:49:33 -05:00
sound	ALSA: sb16 - Fix build errors on MIPS and others with 13bit ioctl size	2011-06-30 15:33:57 +02:00
target	target: Set additional sense length field in sense data	2012-01-25 17:25:00 -08:00
trace	writeback: fix dereferencing NULL bdi->dev on trace_writeback_queue	2012-02-20 12:48:11 -08:00
video	OMAPDSS: HDMI: PHY burnout fix	2012-03-12 10:32:59 -07:00
xen	xen/xenbus: Reject replies with payload > XENSTORE_PAYLOAD_MAX.	2012-01-25 17:24:41 -08:00
Kbuild