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| author | Jesse Melhuish <melhuishj@chromium.org> | 2021-11-15 22:00:52 +0000 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2021-11-16 14:03:11 +0100 |
| commit | 385315decf65902768a0062b4e594f59f013025e (patch) | |
| tree | b40fa0f530df111ff1d43cd2b9907059797f58bc /net/bluetooth/hci_sync.c | |
| parent | a27c519a816437ec92f0ffa3adbc168c2c08725b (diff) | |
| download | lwn-385315decf65902768a0062b4e594f59f013025e.tar.gz lwn-385315decf65902768a0062b4e594f59f013025e.zip | |
Bluetooth: Don't initialize msft/aosp when using user channel
A race condition is triggered when usermode control is given to
userspace before the kernel's MSFT query responds, resulting in an
unexpected response to userspace's reset command.
Issue can be observed in btmon:
< HCI Command: Vendor (0x3f|0x001e) plen 2 #3 [hci0]
05 01 ..
@ USER Open: bt_stack_manage (privileged) version 2.22 {0x0002} [hci0]
< HCI Command: Reset (0x03|0x0003) plen 0 #4 [hci0]
> HCI Event: Command Complete (0x0e) plen 5 #5 [hci0]
Vendor (0x3f|0x001e) ncmd 1
Status: Command Disallowed (0x0c)
05 .
> HCI Event: Command Complete (0x0e) plen 4 #6 [hci0]
Reset (0x03|0x0003) ncmd 2
Status: Success (0x00)
Reviewed-by: Abhishek Pandit-Subedi <abhishekpandit@chromium.org>
Reviewed-by: Sonny Sasaka <sonnysasaka@chromium.org>
Signed-off-by: Jesse Melhuish <melhuishj@chromium.org>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Diffstat (limited to 'net/bluetooth/hci_sync.c')
| -rw-r--r-- | net/bluetooth/hci_sync.c | 12 |
1 files changed, 8 insertions, 4 deletions
diff --git a/net/bluetooth/hci_sync.c b/net/bluetooth/hci_sync.c index b794605dc882..06d08dc6ad22 100644 --- a/net/bluetooth/hci_sync.c +++ b/net/bluetooth/hci_sync.c @@ -3887,8 +3887,10 @@ setup_failed: hci_dev_test_flag(hdev, HCI_VENDOR_DIAG) && hdev->set_diag) ret = hdev->set_diag(hdev, true); - msft_do_open(hdev); - aosp_do_open(hdev); + if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) { + msft_do_open(hdev); + aosp_do_open(hdev); + } clear_bit(HCI_INIT, &hdev->flags); @@ -4031,8 +4033,10 @@ int hci_dev_close_sync(struct hci_dev *hdev) hci_sock_dev_event(hdev, HCI_DEV_DOWN); - aosp_do_close(hdev); - msft_do_close(hdev); + if (!hci_dev_test_flag(hdev, HCI_USER_CHANNEL)) { + aosp_do_close(hdev); + msft_do_close(hdev); + } if (hdev->flush) hdev->flush(hdev); |