LinuxLists.cc - [PATCH] Bluetooth: SMP: Workaround Microsoft Surface Precision Mouse bug

2019-06-18 22:49:39

Subject: [PATCH] Bluetooth: SMP: Workaround Microsoft Surface Precision Mouse bug

Microsoft Surface Precision Mouse provides bogus identity address when
pairing. It connects with Static Random address but provides Public
Address in SMP Identity Address Information PDU. Address has same
value but type is different. Workaround this by dropping IRK if ID
address discrepancy is detected.

> HCI Event: LE Meta Event (0x3e) plen 19
LE Connection Complete (0x01)
Status: Success (0x00)
Handle: 75
Role: Master (0x00)
Peer address type: Random (0x01)
Peer address: E0:52:33:93:3B:21 (Static)
Connection interval: 50.00 msec (0x0028)
Connection latency: 0 (0x0000)
Supervision timeout: 420 msec (0x002a)
Master clock accuracy: 0x00

....

> ACL Data RX: Handle 75 flags 0x02 dlen 12
SMP: Identity Address Information (0x09) len 7
Address type: Public (0x00)
Address: E0:52:33:93:3B:21

Signed-off-by: Szymon Janc <[email protected]>
Tested-by: Maarten Fonville <[email protected]>
Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199461
Cc: [email protected]
---
net/bluetooth/smp.c | 14 ++++++++++++++
1 file changed, 14 insertions(+)

diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index e68c715f8d37..d528d95a2c27 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -2579,6 +2579,20 @@ static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
goto distribute;
}

+ /*
+ * Drop IRK if peer is using identity address during pairing but is
+ * providing different address as identity information.
+ *
+ * Microsoft Surface Precision Mouse is known to have this bug.
+ */
+ if (hci_is_identity_address(&hcon->dst, hcon->dst_type) &&
+ (bacmp(&info->bdaddr, &hcon->dst) ||
+ info->addr_type != hcon->dst_type)) {
+ bt_dev_err(hcon->hdev,
+ "ignoring IRK with invalid identity address");
+ goto distribute;
+ }
+
bacpy(&smp->id_addr, &info->bdaddr);
smp->id_addr_type = info->addr_type;

--
2.21.0

2019-07-06 14:01:23

by Marcel Holtmann

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Subject: Re: [PATCH] Bluetooth: SMP: Workaround Microsoft Surface Precision Mouse bug

Hi Szymon,

> Microsoft Surface Precision Mouse provides bogus identity address when
> pairing. It connects with Static Random address but provides Public
> Address in SMP Identity Address Information PDU. Address has same
> value but type is different. Workaround this by dropping IRK if ID
> address discrepancy is detected.
>
>> HCI Event: LE Meta Event (0x3e) plen 19
> LE Connection Complete (0x01)
> Status: Success (0x00)
> Handle: 75
> Role: Master (0x00)
> Peer address type: Random (0x01)
> Peer address: E0:52:33:93:3B:21 (Static)
> Connection interval: 50.00 msec (0x0028)
> Connection latency: 0 (0x0000)
> Supervision timeout: 420 msec (0x002a)
> Master clock accuracy: 0x00
>
> ....
>
>> ACL Data RX: Handle 75 flags 0x02 dlen 12
> SMP: Identity Address Information (0x09) len 7
> Address type: Public (0x00)
> Address: E0:52:33:93:3B:21
>
> Signed-off-by: Szymon Janc <[email protected]>
> Tested-by: Maarten Fonville <[email protected]>
> Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=199461
> Cc: [email protected]
> ---
> net/bluetooth/smp.c | 14 ++++++++++++++
> 1 file changed, 14 insertions(+)

patch has been applied to bluetooth-next tree.

Regards

Marcel

2019-07-06 14:05:59

by Marcel Holtmann

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