* [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close [not found] <20120315134735.GA19821@localhost> @ 2012-03-15 13:48 ` Johan Hovold 2012-03-15 13:48 ` [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister Johan Hovold 2012-03-15 15:21 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Marcel Holtmann 0 siblings, 2 replies; 9+ messages in thread From: Johan Hovold @ 2012-03-15 13:48 UTC (permalink / raw) To: Marcel Holtmann, Gustavo F. Padovan Cc: David S. Miller, linux-bluetooth, linux-kernel, netdev, David Herrmann, Greg KH, Johan Hovold, stable Do not close protocol driver until device has been unregistered. This fixes a race between tty_close and hci_dev_open which can result in a NULL-pointer dereference. The line discipline closes the protocol driver while we may still have hci_dev_open sleeping on the req_lock mutex resulting in a NULL-pointer dereference when lock is acquired and hci_init_req called. Bug is 100% reproducible using hciattach and a disconnected serial port: 0. # hciattach -n 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 detaches protocol driver and cancels init req 5. hci_dev_open (1) releases req lock 6. hci_dev_open (3) grabs req lock, calls hci_init_req, which triggers oops when request is prepared in hci_uart_send_frame [ 137.201263] Unable to handle kernel NULL pointer dereference at virtual address 00000028 [ 137.209838] pgd = c0004000 [ 137.212677] [00000028] *pgd=00000000 [ 137.216430] Internal error: Oops: 17 [#1] [ 137.220642] Modules linked in: [ 137.223846] CPU: 0 Tainted: G W (3.3.0-rc6-dirty #406) [ 137.230529] PC is at __lock_acquire+0x5c/0x1ab0 [ 137.235290] LR is at lock_acquire+0x9c/0x128 [ 137.239776] pc : [<c0071490>] lr : [<c00733f8>] psr: 20000093 [ 137.239776] sp : cf869dd8 ip : c0529554 fp : c051c730 [ 137.251800] r10: 00000000 r9 : cf8673c0 r8 : 00000080 [ 137.257293] r7 : 00000028 r6 : 00000002 r5 : 00000000 r4 : c053fd70 [ 137.264129] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000001 [ 137.270965] Flags: nzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel [ 137.278717] Control: 10c5387d Table: 8f0f4019 DAC: 00000015 [ 137.284729] Process kworker/u:1 (pid: 7, stack limit = 0xcf8682e8) [ 137.291229] Stack: (0xcf869dd8 to 0xcf86a000) [ 137.295776] 9dc0: c0529554 00000000 [ 137.304351] 9de0: cf8673c0 cf868000 d03ea1ef cf868000 000001ef 00000470 00000000 00000002 [ 137.312927] 9e00: cf8673c0 00000001 c051c730 c00716ec 0000000c 00000440 c0529554 00000001 [ 137.321533] 9e20: c051c730 cf868000 d03ea1f3 00000000 c053b978 00000000 00000028 cf868000 [ 137.330078] 9e40: 00000000 00000000 00000002 00000000 00000000 c00733f8 00000002 00000080 [ 137.338684] 9e60: 00000000 c02a1d50 00000000 00000001 60000013 c0969a1c 60000093 c053b96c [ 137.347259] 9e80: 00000002 00000018 20000013 c02a1d50 cf0ac000 00000000 00000002 cf868000 [ 137.355834] 9ea0: 00000089 c0374130 00000002 00000000 c02a1d50 cf0ac000 0000000c cf0fc540 [ 137.364410] 9ec0: 00000018 c02a1d50 cf0fc540 00000000 cf0fc540 c0282238 c028220c cf178d80 [ 137.372985] 9ee0: 127525d8 c02821cc 9a1fa451 c032727c 9a1fa451 127525d8 cf0fc540 cf0ac4ec [ 137.381561] 9f00: cf0ac000 cf0fc540 cf0ac584 c03285f4 c0328580 cf0ac4ec cf85c740 c05510cc [ 137.390136] 9f20: ce825400 c004c914 00000002 00000000 c004c884 ce8254f5 cf869f48 00000000 [ 137.398712] 9f40: c0328580 ce825415 c0a7f914 c061af64 00000000 c048cf3c cf8673c0 cf85c740 [ 137.407287] 9f60: c05510cc c051a66c c05510ec c05510c4 cf85c750 cf868000 00000089 c004d6ac [ 137.415863] 9f80: 00000000 c0073d14 00000001 cf853ed8 cf85c740 c004d558 00000013 00000000 [ 137.424438] 9fa0: 00000000 00000000 00000000 c00516b0 00000000 00000000 cf85c740 00000000 [ 137.433013] 9fc0: 00000001 dead4ead ffffffff ffffffff c0551674 00000000 00000000 c0450aa4 [ 137.441589] 9fe0: cf869fe0 cf869fe0 cf853ed8 c005162c c0013b30 c0013b30 00ffff00 00ffff00 [ 137.450164] [<c0071490>] (__lock_acquire+0x5c/0x1ab0) from [<c00733f8>] (lock_acquire+0x9c/0x128) [ 137.459503] [<c00733f8>] (lock_acquire+0x9c/0x128) from [<c0374130>] (_raw_spin_lock_irqsave+0x44/0x58) [ 137.469360] [<c0374130>] (_raw_spin_lock_irqsave+0x44/0x58) from [<c02a1d50>] (skb_queue_tail+0x18/0x48) [ 137.479339] [<c02a1d50>] (skb_queue_tail+0x18/0x48) from [<c0282238>] (h4_enqueue+0x2c/0x34) [ 137.488189] [<c0282238>] (h4_enqueue+0x2c/0x34) from [<c02821cc>] (hci_uart_send_frame+0x34/0x68) [ 137.497497] [<c02821cc>] (hci_uart_send_frame+0x34/0x68) from [<c032727c>] (hci_send_frame+0x50/0x88) [ 137.507171] [<c032727c>] (hci_send_frame+0x50/0x88) from [<c03285f4>] (hci_cmd_work+0x74/0xd4) [ 137.516204] [<c03285f4>] (hci_cmd_work+0x74/0xd4) from [<c004c914>] (process_one_work+0x1a0/0x4ec) [ 137.525604] [<c004c914>] (process_one_work+0x1a0/0x4ec) from [<c004d6ac>] (worker_thread+0x154/0x344) [ 137.535278] [<c004d6ac>] (worker_thread+0x154/0x344) from [<c00516b0>] (kthread+0x84/0x90) [ 137.543975] [<c00516b0>] (kthread+0x84/0x90) from [<c0013b30>] (kernel_thread_exit+0x0/0x8) [ 137.552734] Code: e59f4e5c e5941000 e3510000 0a000031 (e5971000) [ 137.559234] ---[ end trace 1b75b31a2719ed1e ]--- Cc: stable <stable@vger.kernel.org> Signed-off-by: Johan Hovold <jhovold@gmail.com> --- drivers/bluetooth/hci_ldisc.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/bluetooth/hci_ldisc.c b/drivers/bluetooth/hci_ldisc.c index fd5adb4..98a8c05 100644 --- a/drivers/bluetooth/hci_ldisc.c +++ b/drivers/bluetooth/hci_ldisc.c @@ -299,11 +299,11 @@ static void hci_uart_tty_close(struct tty_struct *tty) hci_uart_close(hdev); if (test_and_clear_bit(HCI_UART_PROTO_SET, &hu->flags)) { - hu->proto->close(hu); if (hdev) { hci_unregister_dev(hdev); hci_free_dev(hdev); } + hu->proto->close(hu); } kfree(hu); -- 1.7.8.4 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister 2012-03-15 13:48 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Johan Hovold @ 2012-03-15 13:48 ` Johan Hovold 2012-03-15 15:23 ` Marcel Holtmann 2012-03-15 15:21 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Marcel Holtmann 1 sibling, 1 reply; 9+ messages in thread From: Johan Hovold @ 2012-03-15 13:48 UTC (permalink / raw) To: Marcel Holtmann, Gustavo F. Padovan Cc: David S. Miller, linux-bluetooth, linux-kernel, netdev, David Herrmann, Greg KH, Johan Hovold, stable 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 Cc: stable <stable@vger.kernel.org> Signed-off-by: Johan Hovold <jhovold@gmail.com> --- include/net/bluetooth/hci.h | 1 + net/bluetooth/hci_core.c | 7 +++++++ 2 files changed, 8 insertions(+), 0 deletions(-) diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index 344b0f9..8f928f7 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -92,6 +92,7 @@ enum { HCI_SERVICE_CACHE, HCI_LINK_KEYS, HCI_DEBUG_KEYS, + HCI_UNREGISTER, HCI_LE_SCAN, HCI_SSP_ENABLED, diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 2f3e1bb..2e3f193 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -666,6 +666,11 @@ int hci_dev_open(__u16 dev) hci_req_lock(hdev); + if (test_bit(HCI_UNREGISTER, &hdev->dev_flags)) { + ret = -ENODEV; + goto done; + } + if (hdev->rfkill && rfkill_blocked(hdev->rfkill)) { ret = -ERFKILL; goto done; @@ -1850,6 +1855,8 @@ void hci_unregister_dev(struct hci_dev *hdev) BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); + set_bit(HCI_UNREGISTER, &hdev->dev_flags); + write_lock(&hci_dev_list_lock); list_del(&hdev->list); write_unlock(&hci_dev_list_lock); -- 1.7.8.4 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister 2012-03-15 13:48 ` [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister Johan Hovold @ 2012-03-15 15:23 ` Marcel Holtmann 0 siblings, 0 replies; 9+ messages in thread From: Marcel Holtmann @ 2012-03-15 15:23 UTC (permalink / raw) To: Johan Hovold Cc: Gustavo F. Padovan, David S. Miller, linux-bluetooth, linux-kernel, netdev, David Herrmann, Greg KH, stable Hi Johan, > 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 > > Cc: stable <stable@vger.kernel.org> > Signed-off-by: Johan Hovold <jhovold@gmail.com> > --- > include/net/bluetooth/hci.h | 1 + > net/bluetooth/hci_core.c | 7 +++++++ > 2 files changed, 8 insertions(+), 0 deletions(-) Acked-by: Marcel Holtmann <marcel@holtmann.org> Regards Marcel ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close 2012-03-15 13:48 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Johan Hovold 2012-03-15 13:48 ` [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister Johan Hovold @ 2012-03-15 15:21 ` Marcel Holtmann 2012-03-16 16:03 ` Johan Hedberg 1 sibling, 1 reply; 9+ messages in thread From: Marcel Holtmann @ 2012-03-15 15:21 UTC (permalink / raw) To: Johan Hovold Cc: Gustavo F. Padovan, David S. Miller, linux-bluetooth, linux-kernel, netdev, David Herrmann, Greg KH, stable Hi Johan, > Do not close protocol driver until device has been unregistered. > > This fixes a race between tty_close and hci_dev_open which can result in > a NULL-pointer dereference. > > The line discipline closes the protocol driver while we may still have > hci_dev_open sleeping on the req_lock mutex resulting in a NULL-pointer > dereference when lock is acquired and hci_init_req called. > > Bug is 100% reproducible using hciattach and a disconnected serial port: > > 0. # hciattach -n 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 detaches protocol driver and cancels init req > 5. hci_dev_open (1) releases req lock > 6. hci_dev_open (3) grabs req lock, calls hci_init_req, which triggers oops > when request is prepared in hci_uart_send_frame > > [ 137.201263] Unable to handle kernel NULL pointer dereference at virtual address 00000028 > [ 137.209838] pgd = c0004000 > [ 137.212677] [00000028] *pgd=00000000 > [ 137.216430] Internal error: Oops: 17 [#1] > [ 137.220642] Modules linked in: > [ 137.223846] CPU: 0 Tainted: G W (3.3.0-rc6-dirty #406) > [ 137.230529] PC is at __lock_acquire+0x5c/0x1ab0 > [ 137.235290] LR is at lock_acquire+0x9c/0x128 > [ 137.239776] pc : [<c0071490>] lr : [<c00733f8>] psr: 20000093 > [ 137.239776] sp : cf869dd8 ip : c0529554 fp : c051c730 > [ 137.251800] r10: 00000000 r9 : cf8673c0 r8 : 00000080 > [ 137.257293] r7 : 00000028 r6 : 00000002 r5 : 00000000 r4 : c053fd70 > [ 137.264129] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000001 > [ 137.270965] Flags: nzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel > [ 137.278717] Control: 10c5387d Table: 8f0f4019 DAC: 00000015 > [ 137.284729] Process kworker/u:1 (pid: 7, stack limit = 0xcf8682e8) > [ 137.291229] Stack: (0xcf869dd8 to 0xcf86a000) > [ 137.295776] 9dc0: c0529554 00000000 > [ 137.304351] 9de0: cf8673c0 cf868000 d03ea1ef cf868000 000001ef 00000470 00000000 00000002 > [ 137.312927] 9e00: cf8673c0 00000001 c051c730 c00716ec 0000000c 00000440 c0529554 00000001 > [ 137.321533] 9e20: c051c730 cf868000 d03ea1f3 00000000 c053b978 00000000 00000028 cf868000 > [ 137.330078] 9e40: 00000000 00000000 00000002 00000000 00000000 c00733f8 00000002 00000080 > [ 137.338684] 9e60: 00000000 c02a1d50 00000000 00000001 60000013 c0969a1c 60000093 c053b96c > [ 137.347259] 9e80: 00000002 00000018 20000013 c02a1d50 cf0ac000 00000000 00000002 cf868000 > [ 137.355834] 9ea0: 00000089 c0374130 00000002 00000000 c02a1d50 cf0ac000 0000000c cf0fc540 > [ 137.364410] 9ec0: 00000018 c02a1d50 cf0fc540 00000000 cf0fc540 c0282238 c028220c cf178d80 > [ 137.372985] 9ee0: 127525d8 c02821cc 9a1fa451 c032727c 9a1fa451 127525d8 cf0fc540 cf0ac4ec > [ 137.381561] 9f00: cf0ac000 cf0fc540 cf0ac584 c03285f4 c0328580 cf0ac4ec cf85c740 c05510cc > [ 137.390136] 9f20: ce825400 c004c914 00000002 00000000 c004c884 ce8254f5 cf869f48 00000000 > [ 137.398712] 9f40: c0328580 ce825415 c0a7f914 c061af64 00000000 c048cf3c cf8673c0 cf85c740 > [ 137.407287] 9f60: c05510cc c051a66c c05510ec c05510c4 cf85c750 cf868000 00000089 c004d6ac > [ 137.415863] 9f80: 00000000 c0073d14 00000001 cf853ed8 cf85c740 c004d558 00000013 00000000 > [ 137.424438] 9fa0: 00000000 00000000 00000000 c00516b0 00000000 00000000 cf85c740 00000000 > [ 137.433013] 9fc0: 00000001 dead4ead ffffffff ffffffff c0551674 00000000 00000000 c0450aa4 > [ 137.441589] 9fe0: cf869fe0 cf869fe0 cf853ed8 c005162c c0013b30 c0013b30 00ffff00 00ffff00 > [ 137.450164] [<c0071490>] (__lock_acquire+0x5c/0x1ab0) from [<c00733f8>] (lock_acquire+0x9c/0x128) > [ 137.459503] [<c00733f8>] (lock_acquire+0x9c/0x128) from [<c0374130>] (_raw_spin_lock_irqsave+0x44/0x58) > [ 137.469360] [<c0374130>] (_raw_spin_lock_irqsave+0x44/0x58) from [<c02a1d50>] (skb_queue_tail+0x18/0x48) > [ 137.479339] [<c02a1d50>] (skb_queue_tail+0x18/0x48) from [<c0282238>] (h4_enqueue+0x2c/0x34) > [ 137.488189] [<c0282238>] (h4_enqueue+0x2c/0x34) from [<c02821cc>] (hci_uart_send_frame+0x34/0x68) > [ 137.497497] [<c02821cc>] (hci_uart_send_frame+0x34/0x68) from [<c032727c>] (hci_send_frame+0x50/0x88) > [ 137.507171] [<c032727c>] (hci_send_frame+0x50/0x88) from [<c03285f4>] (hci_cmd_work+0x74/0xd4) > [ 137.516204] [<c03285f4>] (hci_cmd_work+0x74/0xd4) from [<c004c914>] (process_one_work+0x1a0/0x4ec) > [ 137.525604] [<c004c914>] (process_one_work+0x1a0/0x4ec) from [<c004d6ac>] (worker_thread+0x154/0x344) > [ 137.535278] [<c004d6ac>] (worker_thread+0x154/0x344) from [<c00516b0>] (kthread+0x84/0x90) > [ 137.543975] [<c00516b0>] (kthread+0x84/0x90) from [<c0013b30>] (kernel_thread_exit+0x0/0x8) > [ 137.552734] Code: e59f4e5c e5941000 e3510000 0a000031 (e5971000) > [ 137.559234] ---[ end trace 1b75b31a2719ed1e ]--- > > Cc: stable <stable@vger.kernel.org> > Signed-off-by: Johan Hovold <jhovold@gmail.com> > --- > drivers/bluetooth/hci_ldisc.c | 2 +- > 1 files changed, 1 insertions(+), 1 deletions(-) Acked-by: Marcel Holtmann <marcel@holtmann.org> Regards Marcel ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close 2012-03-15 15:21 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Marcel Holtmann @ 2012-03-16 16:03 ` Johan Hedberg 0 siblings, 0 replies; 9+ messages in thread From: Johan Hedberg @ 2012-03-16 16:03 UTC (permalink / raw) To: Marcel Holtmann Cc: Johan Hovold, Gustavo F. Padovan, David S. Miller, linux-bluetooth, linux-kernel, netdev, David Herrmann, Greg KH, stable Hi, On Thu, Mar 15, 2012, Marcel Holtmann wrote: > Hi Johan, > > > Do not close protocol driver until device has been unregistered. > > > > This fixes a race between tty_close and hci_dev_open which can result in > > a NULL-pointer dereference. > > > > The line discipline closes the protocol driver while we may still have > > hci_dev_open sleeping on the req_lock mutex resulting in a NULL-pointer > > dereference when lock is acquired and hci_init_req called. > > > > Bug is 100% reproducible using hciattach and a disconnected serial port: > > > > 0. # hciattach -n 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 detaches protocol driver and cancels init req > > 5. hci_dev_open (1) releases req lock > > 6. hci_dev_open (3) grabs req lock, calls hci_init_req, which triggers oops > > when request is prepared in hci_uart_send_frame > > > > [ 137.201263] Unable to handle kernel NULL pointer dereference at virtual address 00000028 > > [ 137.209838] pgd = c0004000 > > [ 137.212677] [00000028] *pgd=00000000 > > [ 137.216430] Internal error: Oops: 17 [#1] > > [ 137.220642] Modules linked in: > > [ 137.223846] CPU: 0 Tainted: G W (3.3.0-rc6-dirty #406) > > [ 137.230529] PC is at __lock_acquire+0x5c/0x1ab0 > > [ 137.235290] LR is at lock_acquire+0x9c/0x128 > > [ 137.239776] pc : [<c0071490>] lr : [<c00733f8>] psr: 20000093 > > [ 137.239776] sp : cf869dd8 ip : c0529554 fp : c051c730 > > [ 137.251800] r10: 00000000 r9 : cf8673c0 r8 : 00000080 > > [ 137.257293] r7 : 00000028 r6 : 00000002 r5 : 00000000 r4 : c053fd70 > > [ 137.264129] r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000001 > > [ 137.270965] Flags: nzCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment kernel > > [ 137.278717] Control: 10c5387d Table: 8f0f4019 DAC: 00000015 > > [ 137.284729] Process kworker/u:1 (pid: 7, stack limit = 0xcf8682e8) > > [ 137.291229] Stack: (0xcf869dd8 to 0xcf86a000) > > [ 137.295776] 9dc0: c0529554 00000000 > > [ 137.304351] 9de0: cf8673c0 cf868000 d03ea1ef cf868000 000001ef 00000470 00000000 00000002 > > [ 137.312927] 9e00: cf8673c0 00000001 c051c730 c00716ec 0000000c 00000440 c0529554 00000001 > > [ 137.321533] 9e20: c051c730 cf868000 d03ea1f3 00000000 c053b978 00000000 00000028 cf868000 > > [ 137.330078] 9e40: 00000000 00000000 00000002 00000000 00000000 c00733f8 00000002 00000080 > > [ 137.338684] 9e60: 00000000 c02a1d50 00000000 00000001 60000013 c0969a1c 60000093 c053b96c > > [ 137.347259] 9e80: 00000002 00000018 20000013 c02a1d50 cf0ac000 00000000 00000002 cf868000 > > [ 137.355834] 9ea0: 00000089 c0374130 00000002 00000000 c02a1d50 cf0ac000 0000000c cf0fc540 > > [ 137.364410] 9ec0: 00000018 c02a1d50 cf0fc540 00000000 cf0fc540 c0282238 c028220c cf178d80 > > [ 137.372985] 9ee0: 127525d8 c02821cc 9a1fa451 c032727c 9a1fa451 127525d8 cf0fc540 cf0ac4ec > > [ 137.381561] 9f00: cf0ac000 cf0fc540 cf0ac584 c03285f4 c0328580 cf0ac4ec cf85c740 c05510cc > > [ 137.390136] 9f20: ce825400 c004c914 00000002 00000000 c004c884 ce8254f5 cf869f48 00000000 > > [ 137.398712] 9f40: c0328580 ce825415 c0a7f914 c061af64 00000000 c048cf3c cf8673c0 cf85c740 > > [ 137.407287] 9f60: c05510cc c051a66c c05510ec c05510c4 cf85c750 cf868000 00000089 c004d6ac > > [ 137.415863] 9f80: 00000000 c0073d14 00000001 cf853ed8 cf85c740 c004d558 00000013 00000000 > > [ 137.424438] 9fa0: 00000000 00000000 00000000 c00516b0 00000000 00000000 cf85c740 00000000 > > [ 137.433013] 9fc0: 00000001 dead4ead ffffffff ffffffff c0551674 00000000 00000000 c0450aa4 > > [ 137.441589] 9fe0: cf869fe0 cf869fe0 cf853ed8 c005162c c0013b30 c0013b30 00ffff00 00ffff00 > > [ 137.450164] [<c0071490>] (__lock_acquire+0x5c/0x1ab0) from [<c00733f8>] (lock_acquire+0x9c/0x128) > > [ 137.459503] [<c00733f8>] (lock_acquire+0x9c/0x128) from [<c0374130>] (_raw_spin_lock_irqsave+0x44/0x58) > > [ 137.469360] [<c0374130>] (_raw_spin_lock_irqsave+0x44/0x58) from [<c02a1d50>] (skb_queue_tail+0x18/0x48) > > [ 137.479339] [<c02a1d50>] (skb_queue_tail+0x18/0x48) from [<c0282238>] (h4_enqueue+0x2c/0x34) > > [ 137.488189] [<c0282238>] (h4_enqueue+0x2c/0x34) from [<c02821cc>] (hci_uart_send_frame+0x34/0x68) > > [ 137.497497] [<c02821cc>] (hci_uart_send_frame+0x34/0x68) from [<c032727c>] (hci_send_frame+0x50/0x88) > > [ 137.507171] [<c032727c>] (hci_send_frame+0x50/0x88) from [<c03285f4>] (hci_cmd_work+0x74/0xd4) > > [ 137.516204] [<c03285f4>] (hci_cmd_work+0x74/0xd4) from [<c004c914>] (process_one_work+0x1a0/0x4ec) > > [ 137.525604] [<c004c914>] (process_one_work+0x1a0/0x4ec) from [<c004d6ac>] (worker_thread+0x154/0x344) > > [ 137.535278] [<c004d6ac>] (worker_thread+0x154/0x344) from [<c00516b0>] (kthread+0x84/0x90) > > [ 137.543975] [<c00516b0>] (kthread+0x84/0x90) from [<c0013b30>] (kernel_thread_exit+0x0/0x8) > > [ 137.552734] Code: e59f4e5c e5941000 e3510000 0a000031 (e5971000) > > [ 137.559234] ---[ end trace 1b75b31a2719ed1e ]--- > > > > Cc: stable <stable@vger.kernel.org> > > Signed-off-by: Johan Hovold <jhovold@gmail.com> > > --- > > drivers/bluetooth/hci_ldisc.c | 2 +- > > 1 files changed, 1 insertions(+), 1 deletions(-) > > Acked-by: Marcel Holtmann <marcel@holtmann.org> Both patches have been applied to my bluetooth-next tree. Thanks. Johan ^ permalink raw reply [flat|nested] 9+ messages in thread
[parent not found: <1331136120-27075-1-git-send-email-jhovold@gmail.com>]
* [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister [not found] <1331136120-27075-1-git-send-email-jhovold@gmail.com> @ 2012-03-07 16:02 ` Johan Hovold 2012-03-07 19:29 ` Marcel Holtmann 0 siblings, 1 reply; 9+ messages in thread From: Johan Hovold @ 2012-03-07 16:02 UTC (permalink / raw) To: Marcel Holtmann, Gustavo F. Padovan Cc: David S. Miller, linux-bluetooth, linux-kernel, netdev, Johan Hovold, stable 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 Cc: stable <stable@vger.kernel.org> Signed-off-by: Johan Hovold <jhovold@gmail.com> --- include/net/bluetooth/hci.h | 1 + net/bluetooth/hci_core.c | 7 +++++++ 2 files changed, 8 insertions(+), 0 deletions(-) diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h index 00596e8..f626f44 100644 --- a/include/net/bluetooth/hci.h +++ b/include/net/bluetooth/hci.h @@ -86,6 +86,7 @@ enum { HCI_DEBUG_KEYS, HCI_RESET, + HCI_UNREGISTER, }; /* diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index 5aeb624..3937ce3 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -525,6 +525,11 @@ int hci_dev_open(__u16 dev) hci_req_lock(hdev); + if (test_bit(HCI_UNREGISTER, &hdev->flags)) { + ret = -ENODEV; + goto done; + } + if (hdev->rfkill && rfkill_blocked(hdev->rfkill)) { ret = -ERFKILL; goto done; @@ -1577,6 +1582,8 @@ void hci_unregister_dev(struct hci_dev *hdev) BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); + set_bit(HCI_UNREGISTER, &hdev->flags); + write_lock(&hci_dev_list_lock); list_del(&hdev->list); write_unlock(&hci_dev_list_lock); -- 1.7.8.4 ^ permalink raw reply related [flat|nested] 9+ messages in thread
* Re: [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister 2012-03-07 16:02 ` [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister Johan Hovold @ 2012-03-07 19:29 ` Marcel Holtmann 2012-03-08 11:56 ` Johan Hovold 0 siblings, 1 reply; 9+ messages in thread From: Marcel Holtmann @ 2012-03-07 19:29 UTC (permalink / raw) To: Johan Hovold Cc: Gustavo F. Padovan, David S. Miller, linux-bluetooth, linux-kernel, netdev, stable Hi Johan, > 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 > > Cc: stable <stable@vger.kernel.org> > Signed-off-by: Johan Hovold <jhovold@gmail.com> > --- > include/net/bluetooth/hci.h | 1 + > net/bluetooth/hci_core.c | 7 +++++++ > 2 files changed, 8 insertions(+), 0 deletions(-) > > diff --git a/include/net/bluetooth/hci.h b/include/net/bluetooth/hci.h > index 00596e8..f626f44 100644 > --- a/include/net/bluetooth/hci.h > +++ b/include/net/bluetooth/hci.h > @@ -86,6 +86,7 @@ enum { > HCI_DEBUG_KEYS, > > HCI_RESET, > + HCI_UNREGISTER, > }; what version of the kernel is this patch against? Since we cleaned up the flags in bluetooth-next tree. Also in addition you can not just add flags here. > > /* > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c > index 5aeb624..3937ce3 100644 > --- a/net/bluetooth/hci_core.c > +++ b/net/bluetooth/hci_core.c > @@ -525,6 +525,11 @@ int hci_dev_open(__u16 dev) > > hci_req_lock(hdev); > > + if (test_bit(HCI_UNREGISTER, &hdev->flags)) { > + ret = -ENODEV; > + goto done; > + } > + > if (hdev->rfkill && rfkill_blocked(hdev->rfkill)) { > ret = -ERFKILL; > goto done; > @@ -1577,6 +1582,8 @@ void hci_unregister_dev(struct hci_dev *hdev) > > BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); > > + set_bit(HCI_UNREGISTER, &hdev->flags); > + > write_lock(&hci_dev_list_lock); > list_del(&hdev->list); > write_unlock(&hci_dev_list_lock); Is this really enough to protect this race condition? Regards Marcel ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister 2012-03-07 19:29 ` Marcel Holtmann @ 2012-03-08 11:56 ` Johan Hovold 2012-03-08 17:43 ` Marcel Holtmann 0 siblings, 1 reply; 9+ messages in thread From: Johan Hovold @ 2012-03-08 11:56 UTC (permalink / raw) To: Marcel Holtmann Cc: Gustavo F. Padovan, David S. Miller, linux-bluetooth, linux-kernel, netdev, stable Hi Marcel, On Wed, Mar 07, 2012 at 11:29:20AM -0800, Marcel Holtmann wrote: > Hi Johan, > > > 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. [...] > what version of the kernel is this patch against? Since we cleaned up > the flags in bluetooth-next tree. Also in addition you can not just add > flags here. As this to be fixed in 3.3 it is against 3.3-rc6. > > /* > > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c > > index 5aeb624..3937ce3 100644 > > --- a/net/bluetooth/hci_core.c > > +++ b/net/bluetooth/hci_core.c > > @@ -525,6 +525,11 @@ int hci_dev_open(__u16 dev) > > > > hci_req_lock(hdev); > > > > + if (test_bit(HCI_UNREGISTER, &hdev->flags)) { > > + ret = -ENODEV; > > + goto done; > > + } > > + > > if (hdev->rfkill && rfkill_blocked(hdev->rfkill)) { > > ret = -ERFKILL; > > goto done; > > @@ -1577,6 +1582,8 @@ void hci_unregister_dev(struct hci_dev *hdev) > > > > BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); > > > > + set_bit(HCI_UNREGISTER, &hdev->flags); > > + > > write_lock(&hci_dev_list_lock); > > list_del(&hdev->list); > > write_unlock(&hci_dev_list_lock); > > Is this really enough to protect this race condition? 1. first hci_dev_open grabs req lock 2. second hci_dev_open sleeps on req lock 3. hci_dev_unregister sleep on req lock (in do_close) 4. first hci_dev_open times out and releases req lock Now either a) the second open grabs the lock or b) close does. a) The second open will time out eventually as well and setting a flag at unregister will only speed things up (at least when the first patch in my series is applied -- otherwise this leads to a NULL-pointer exception as well). b) If close grabs the lock while we have open sleeping on it things go really bad and this is the case this patch intends to fix. As far as I can see, a flag set at unregister (before acquiring the lock) will suffice to fix this race, but perhaps I'm missing something? Where should such an internal flag be added as hdev->flags can not be used? hdev->dev_flags? Thanks, Johan ^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister 2012-03-08 11:56 ` Johan Hovold @ 2012-03-08 17:43 ` Marcel Holtmann 0 siblings, 0 replies; 9+ messages in thread From: Marcel Holtmann @ 2012-03-08 17:43 UTC (permalink / raw) To: Johan Hovold Cc: Gustavo F. Padovan, David S. Miller, linux-bluetooth, linux-kernel, netdev, stable Hi Johan, > > > 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. > > [...] > > > what version of the kernel is this patch against? Since we cleaned up > > the flags in bluetooth-next tree. Also in addition you can not just add > > flags here. > > As this to be fixed in 3.3 it is against 3.3-rc6. > > > > /* > > > diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c > > > index 5aeb624..3937ce3 100644 > > > --- a/net/bluetooth/hci_core.c > > > +++ b/net/bluetooth/hci_core.c > > > @@ -525,6 +525,11 @@ int hci_dev_open(__u16 dev) > > > > > > hci_req_lock(hdev); > > > > > > + if (test_bit(HCI_UNREGISTER, &hdev->flags)) { > > > + ret = -ENODEV; > > > + goto done; > > > + } > > > + > > > if (hdev->rfkill && rfkill_blocked(hdev->rfkill)) { > > > ret = -ERFKILL; > > > goto done; > > > @@ -1577,6 +1582,8 @@ void hci_unregister_dev(struct hci_dev *hdev) > > > > > > BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); > > > > > > + set_bit(HCI_UNREGISTER, &hdev->flags); > > > + > > > write_lock(&hci_dev_list_lock); > > > list_del(&hdev->list); > > > write_unlock(&hci_dev_list_lock); > > > > Is this really enough to protect this race condition? > > 1. first hci_dev_open grabs req lock > 2. second hci_dev_open sleeps on req lock > 3. hci_dev_unregister sleep on req lock (in do_close) > 4. first hci_dev_open times out and releases req lock > > Now either a) the second open grabs the lock or b) close does. > > a) The second open will time out eventually as well and setting a flag > at unregister will only speed things up (at least when the first > patch in my series is applied -- otherwise this leads to a > NULL-pointer exception as well). > > b) If close grabs the lock while we have open sleeping on it things go > really bad and this is the case this patch intends to fix. > > As far as I can see, a flag set at unregister (before acquiring the lock) > will suffice to fix this race, but perhaps I'm missing something? > > Where should such an internal flag be added as hdev->flags can not be > used? hdev->dev_flags? please add them to hdev->dev_flags as internal flag. Regards Marcel ^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2012-03-16 16:03 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
[not found] <20120315134735.GA19821@localhost>
2012-03-15 13:48 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Johan Hovold
2012-03-15 13:48 ` [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister Johan Hovold
2012-03-15 15:23 ` Marcel Holtmann
2012-03-15 15:21 ` [PATCH 1/2] bluetooth: hci_ldisc: fix NULL-pointer dereference on tty_close Marcel Holtmann
2012-03-16 16:03 ` Johan Hedberg
[not found] <1331136120-27075-1-git-send-email-jhovold@gmail.com>
2012-03-07 16:02 ` [PATCH 2/2] bluetooth: hci_core: fix NULL-pointer dereference at unregister Johan Hovold
2012-03-07 19:29 ` Marcel Holtmann
2012-03-08 11:56 ` Johan Hovold
2012-03-08 17:43 ` Marcel Holtmann
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox