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| author | Gustavo Padovan <gustavo.padovan@collabora.co.uk> | 2013-07-11 11:34:28 +0100 |
|---|---|---|
| committer | Gustavo Padovan <gustavo.padovan@collabora.co.uk> | 2013-07-25 19:52:36 +0100 |
| commit | fcee337704d76446e0d4714cc5eff53e896f7c6f (patch) | |
| tree | a94aadef90f1e20b76a2bf5005deb815239fd63e /net | |
| parent | 1ebd0b21ab14efb75950079840eac29afea2a26e (diff) | |
| download | blackbird-op-linux-fcee337704d76446e0d4714cc5eff53e896f7c6f.tar.gz blackbird-op-linux-fcee337704d76446e0d4714cc5eff53e896f7c6f.zip | |
Bluetooth: Fix race between hci_register_dev() and hci_dev_open()
If hci_dev_open() is called after hci_register_dev() added the device to
the hci_dev_list but before the workqueue are created we could run into a
NULL pointer dereference (see below).
This bug is very unlikely to happen, systems using bluetoothd to
manage their bluetooth devices will never see this happen.
BUG: unable to handle kernel NULL pointer dereference
0100
IP: [<ffffffff81077502>] __queue_work+0x32/0x3d0
(...)
Call Trace:
[<ffffffff81077be5>] queue_work_on+0x45/0x50
[<ffffffffa016e8ff>] hci_req_run+0xbf/0xf0 [bluetooth]
[<ffffffffa01709b0>] ? hci_init2_req+0x720/0x720 [bluetooth]
[<ffffffffa016ea06>] __hci_req_sync+0xd6/0x1c0 [bluetooth]
[<ffffffff8108ee10>] ? try_to_wake_up+0x2b0/0x2b0
[<ffffffff8150e3f0>] ? usb_autopm_put_interface+0x30/0x40
[<ffffffffa016fad5>] hci_dev_open+0x275/0x2e0 [bluetooth]
[<ffffffffa0182752>] hci_sock_ioctl+0x1f2/0x3f0 [bluetooth]
[<ffffffff815c6050>] sock_do_ioctl+0x30/0x70
[<ffffffff815c75f9>] sock_ioctl+0x79/0x2f0
[<ffffffff811a8046>] do_vfs_ioctl+0x96/0x560
[<ffffffff811a85a1>] SyS_ioctl+0x91/0xb0
[<ffffffff816d989d>] system_call_fastpath+0x1a/0x1f
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>
Diffstat (limited to 'net')
| -rw-r--r-- | net/bluetooth/hci_core.c | 11 |
1 files changed, 4 insertions, 7 deletions
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c index ace5e55fe5a3..64d33d1e14c8 100644 --- a/net/bluetooth/hci_core.c +++ b/net/bluetooth/hci_core.c @@ -2207,10 +2207,6 @@ int hci_register_dev(struct hci_dev *hdev) BT_DBG("%p name %s bus %d", hdev, hdev->name, hdev->bus); - write_lock(&hci_dev_list_lock); - list_add(&hdev->list, &hci_dev_list); - write_unlock(&hci_dev_list_lock); - hdev->workqueue = alloc_workqueue(hdev->name, WQ_HIGHPRI | WQ_UNBOUND | WQ_MEM_RECLAIM, 1); if (!hdev->workqueue) { @@ -2246,6 +2242,10 @@ int hci_register_dev(struct hci_dev *hdev) if (hdev->dev_type != HCI_AMP) set_bit(HCI_AUTO_OFF, &hdev->dev_flags); + write_lock(&hci_dev_list_lock); + list_add(&hdev->list, &hci_dev_list); + write_unlock(&hci_dev_list_lock); + hci_notify(hdev, HCI_DEV_REG); hci_dev_hold(hdev); @@ -2258,9 +2258,6 @@ err_wqueue: destroy_workqueue(hdev->req_workqueue); err: ida_simple_remove(&hci_index_ida, hdev->id); - write_lock(&hci_dev_list_lock); - list_del(&hdev->list); - write_unlock(&hci_dev_list_lock); return error; } |
