Lark client patch for Wayland

lark-wayland-binary-patch.md

Version 7.36.11

The process to make this version work is similar to version 7.28.10. Simply modify /usr/share/applications/bytedance-lark.desktop, adding the --ozone-platform-hint=auto flag to the Exec line.

Set app_id

To fix this, look for this pattern in libframe.so (ui::XDGToplevelWrapperImpl::SetAppId):

55 48 89 e5 49 89 f1 48 8b 7f 20 80 7e 17 00 79 03 4d
8b 09

Replace with:

55 48 89 e5 49 89 f1 48 8b 7f 20 4c 8d 0d 0e 57 8b fa
90 90
                                 ^ Replacement starts here

This hardcodes the string lookup for SetAppId to the string bytedance-feishu.

To update it to bytedance-lark, go to offset 0x029fef30, replacing the value:

62 79 74 65 64 61 6e 63 65 2d 66 65 69 73 68 75

With this:

62 79 74 65 64 61 6e 63 65 2d 6c 61 72 6B

Version 7.28.10

As of version 7.28.10, Lark no longer crashes with SIGILL. In addition, the process of running in Wayland natively has been greatly simplified. It suffices to modify /usr/share/applications/bytedance-lark.desktop, adding the --ozone-platform-hint=auto flag to the Exec line.

However, the flag doesn't seem to propagate to the video meeting client, nor is app_id set correctly.

Unfortunately, it seems to be built on Chromium 121.0.6167.86. For Chinese text input to work, we probably need Chromium 129+ which adds the new --wayland-text-input-version=3 parameter. We will need to wait for ByteDance to update.

Set app_id

To fix this, look for this pattern in libframe.so (ui::XDGToplevelWrapperImpl::SetAppId):

55 48 89 e5 49 89 f1 48 8b 7f 20 80 7e 17 00 79 03 4d
8b 09

Replace with:

55 48 89 e5 49 89 f1 48 8b 7f 20 4c 8d 0d 1e c6 55 fa
90 90
                                 ^ Replacement starts here

This hardcodes the string lookup for SetAppId to the string bytedance-feishu.

To update it to bytedance-lark, go to offset 0x29c0c10, replacing the value:

62 79 74 65 64 61 6e 63 65 2d 66 65 69 73 68 75

With this:

62 79 74 65 64 61 6e 63 65 2d 6c 61 72 6B

Version 7.22.9

When running the Lark/Feishu client under Linux using the flags:

--ozone-platform-hint=wayland

As of version 7.22.9, It crashes with SIGILL.

Crash fix

To fix this, look for this pattern in libframe.so:

48 8b 05 53 26 b7 09 48 89 87 90 00 00 00

Replace the two bytes before the pattern with:

90 90

I have no idea why this code path is being taken. However, replacing the path with no-ops seems to have no visible side effects.

Start via Wayland by default

To start without needing a wrapper script or CLI option, look for this pattern in libframe.so:

55 48 89 e5 41 57 41 56 41 55 41 54 53 48 81 ec 58 01
00 00 64 48 8b 04 25 28 00 00 00 48 89 45 d0 44 8b 35
00 39 bb 0c

Replace the 5th byte onwards with:

b8 02 00 00 00 5d c3

This is equivalent to:

mov eax, 2
pop rbp
ret

There is some code path in the video meeting client that calls XGetWindowProperty even under Wayland, causing a crash like:

X Error of failed request:  BadWindow (invalid Window parameter)
  Major opcode of failed request:  20 (X_GetProperty)
  Resource id in failed request:  0x0
  Serial number of failed request:  104
  Current serial number in output stream:  104

To fix this, look for this pattern in libframe.so:

55 48 89 e5 41 57 41 56 41 55 41 54 53 48 83 ec 38 48
89 7d d0 8a 05 15 8b f3 00 84 c0 0f 84 ca 00 00 00

Replace the 5th byte onwards with:

b8 03 00 00 00 48 89 ec 5d c3

This is equivalent to:

mov eax, 3
pop rbp
ret

This stubs the call to XGetWindowProperty, hardcoding its return value to 3 (BadWindow).

Set app_id

This is needed for the tray icon to be correct.

To fix this, look for this pattern in libframe.so (ui::XDGToplevelWrapperImpl::SetAppId):

55 48 89 e5 49 89 f1 48 8b 7f 20 80 7e 17 00 79
03 4d 8b 09 8b 4f 40 be 03 00 00 00 31 d2 45 31
c0 31 c0

Replace the bytes that come after with:

4c 8d 0d c6 17 7f fa 5d e9 20 ce 9c 03

This hardcodes the string lookup for SetAppId to 0x2e97b00, which is the string bytedance-feishu. This string appears to be unused anywhere else.

To update it to bytedance-lark, go to offset 0x2d97b00, replacing the value:

62 79 74 65 64 61 6e 63 65 2d 66 65 69 73 68 75

With this:

62 79 74 65 64 61 6e 63 65 2d 6c 61 72 6B

Known issues

• There is instability.
  • Sometimes, when dragging text, the Lark client will crash entirely.
  • Sometimes, when joining meetings, the meeting client disappears.
• Hover state can sometimes get broken.
• Tooltip positions in the video meeting client can be wrong.
• Pop-up subtitles window in the video meeting client can't be dragged. However, using the drag modifier on the keyboard (usually Alt) works.
• Chinese IME doesn't work. However, this applies to all Electron-based apps (electron/electron#33662).

Appendix

The following is for my own reference:

• Memory address to file offsets:
  • .text: subtract 0x7FFFE5A01000 from the memory address.
  • .data: subtract 0x7FFFE5A00000 from the memory address.
• Lark 7.22.9 seems to be built on Chromium 109.0.5414.128. This is found by attaching a remote debugger and checking the navigator object.