BT device keeps changing MAC address on each connect

n0rv · 2024-08-19 14:16:19

Hello.

Something happened recently and my trackball (Logitech MX Ergo) started to change MAC address every time it connects to my PC via bluetooth. This is weird, because I use bt devices quite extensively, but this problem occurs only on Arch and only with this specific device. Everything else works perfectly.

I tried to "repair" a few devices to find out what might be causing this, but I'm not sure where to look.
It doesn't seem to be caused by bluez update, because it was long ago. I use default config files with no modifications.

One suspicious thing I noticed, my trackball have this "(random)" label:

~ $ bluetoothctl info E7:13:DE:98:1C:C6 | head -n1 
Device E7:13:DE:98:1C:C6 (random)

while my headset (and a few other devices) does not and its MAC stays the same:

~ $ bluetoothctl info 80:C3:BA:60:F6:0B | head -n1
Device 80:C3:BA:60:F6:0B (public)

Details:

~ $ bluetoothctl info 80:C3:BA:60:F6:0B            
Device 80:C3:BA:60:F6:0B (public)
    Name: MOMENTUM 4
    Alias: MOMENTUM 4
    Class: 0x00240404 (2360324)
    Icon: audio-headset
    Paired: yes
    Bonded: yes
    Trusted: yes
    Blocked: no
    Connected: yes
    LegacyPairing: no
    UUID: Vendor specific           (00000000-deca-fade-deca-deafdecacaff)
    UUID: Headset                   (00001108-0000-1000-8000-00805f9b34fb)
    UUID: Audio Sink                (0000110b-0000-1000-8000-00805f9b34fb)
    UUID: A/V Remote Control Target (0000110c-0000-1000-8000-00805f9b34fb)
    UUID: Advanced Audio Distribu.. (0000110d-0000-1000-8000-00805f9b34fb)
    UUID: A/V Remote Control        (0000110e-0000-1000-8000-00805f9b34fb)
    UUID: Handsfree                 (0000111e-0000-1000-8000-00805f9b34fb)
    UUID: Vendor specific           (a2129ff3-081b-4c45-8afe-469d9c4842ec)
~ $ bluetoothctl info E7:13:DE:98:1C:C6            
Device E7:13:DE:98:1C:C6 (random)
    Name: MX Ergo
    Alias: MX Ergo
    Appearance: 0x03c2 (962)
    Icon: input-mouse
    Paired: yes
    Bonded: yes
    Trusted: yes
    Blocked: no
    Connected: yes
    WakeAllowed: no
    LegacyPairing: no
    UUID: Generic Access Profile    (00001800-0000-1000-8000-00805f9b34fb)
    UUID: Generic Attribute Profile (00001801-0000-1000-8000-00805f9b34fb)
    UUID: Device Information        (0000180a-0000-1000-8000-00805f9b34fb)
    UUID: Battery Service           (0000180f-0000-1000-8000-00805f9b34fb)
    UUID: Human Interface Device    (00001812-0000-1000-8000-00805f9b34fb)
    UUID: Vendor specific           (00010000-0000-1000-8000-011f2000046d)
    Modalias: usb:v046DpB01Dd0022
    Battery Percentage: 0x64 (100)
~ $ bluetoothctl show                  
Controller B8:9A:2A:28:1C:88 (public)
    Manufacturer: 0x0002 (2)
    Version: 0x0b (11)
    Name: Níðhǫggr
    Alias: Níðhǫggr
    Class: 0x00000104 (260)
    Powered: yes
    PowerState: on
    Discoverable: no
    DiscoverableTimeout: 0x000000b4 (180)
    Pairable: no
    UUID: Generic Attribute Profile (00001801-0000-1000-8000-00805f9b34fb)
    UUID: Generic Access Profile    (00001800-0000-1000-8000-00805f9b34fb)
    UUID: PnP Information           (00001200-0000-1000-8000-00805f9b34fb)
    UUID: A/V Remote Control Target (0000110c-0000-1000-8000-00805f9b34fb)
    UUID: A/V Remote Control        (0000110e-0000-1000-8000-00805f9b34fb)
    UUID: Device Information        (0000180a-0000-1000-8000-00805f9b34fb)
    Modalias: usb:v1D6Bp0246d054D
    Discovering: no
    Roles: central
    Roles: peripheral
Advertising Features:
    ActiveInstances: 0x00 (0)
    SupportedInstances: 0x0c (12)
    SupportedIncludes: tx-power
    SupportedIncludes: appearance
    SupportedIncludes: local-name
    SupportedSecondaryChannels: 1M
    SupportedSecondaryChannels: 2M
    SupportedCapabilities.MinTxPower: 0xffffffde (-34)
    SupportedCapabilities.MaxTxPower: 0x0007 (7)
    SupportedCapabilities.MaxAdvLen: 0xfb (251)
    SupportedCapabilities.MaxScnRspLen: 0xfb (251)
    SupportedFeatures: CanSetTxPower
    SupportedFeatures: HardwareOffload
~ $ pacman -Qi bluez 
Name            : bluez
Version         : 5.77-1
Description     : Daemons for the bluetooth protocol stack
Architecture    : x86_64
URL             : http://www.bluez.org/
Licenses        : GPL-2.0-only
Groups          : None
Provides        : None
Depends On      : systemd-libs  dbus  glib2  alsa-lib  glibc
Optional Deps   : None
Required By     : bluez-tools
Optional For    : None
Conflicts With  : None
Replaces        : None
Installed Size  : 1560,76 KiB
Packager        : Andreas Radke <andyrtr@archlinux.org>
Build Date      : wto, 9 lip 2024, 07:06:13
Install Date    : pon, 19 sie 2024, 15:09:14
Install Reason  : Explicitly installed
Install Script  : No
Validated By    : Signature
~ $ pacman -Qi linux 
Name            : linux
Version         : 6.10.5.arch1-1
Description     : The Linux kernel and modules
Architecture    : x86_64
URL             : https://github.com/archlinux/linux
Licenses        : GPL-2.0-only
Groups          : None
Provides        : KSMBD-MODULE  VIRTUALBOX-GUEST-MODULES  WIREGUARD-MODULE
Depends On      : coreutils  initramfs  kmod
Optional Deps   : wireless-regdb: to set the correct wireless channels of your country [installed]
                  linux-firmware: firmware images needed for some devices [installed]
Required By     : None
Optional For    : base
Conflicts With  : None
Replaces        : virtualbox-guest-modules-arch  wireguard-arch
Installed Size  : 135,65 MiB
Packager        : Jan Alexander Steffens (heftig) <heftig@archlinux.org>
Build Date      : czw, 15 sie 2024, 02:25:30
Install Date    : pon, 19 sie 2024, 16:28:19
Install Reason  : Explicitly installed
Install Script  : No
Validated By    : Signature

Last edited by n0rv (2024-08-19 14:34:20)

Lone_Wolf · 2024-08-20 11:54:46

https://unix.stackexchange.com/question … s-on-every looks relevant .

Which kernel are you using ?

Do other kernels (f.e. linux-lts, linux-zen ) also have this ?

seth · 2024-08-20 16:23:57

Sure it's "random" and not just incrementing?
https://wiki.archlinux.org/title/Blueto … ot_pairing
Do you dual-boot windows or use the mouse on a second computer?

Arch Linux

#1 2024-08-19 14:16:19

BT device keeps changing MAC address on each connect

#2 2024-08-20 11:54:46

Re: BT device keeps changing MAC address on each connect

#3 2024-08-20 16:23:57

Re: BT device keeps changing MAC address on each connect

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