v0.10.0 + decreased max_bpp causes protocol error #3118
Description
xrdp version
0.10.0
Detailed xrdp version, build options
xrdp 0.10.0
A Remote Desktop Protocol Server.
Copyright (C) 2004-2024 Jay Sorg, Neutrino Labs, and all contributors.
See https://github.com/neutrinolabs/xrdp for more information.
Configure options:
--build=x86_64-redhat-linux-gnu
--host=x86_64-redhat-linux-gnu
--program-prefix=
--disable-dependency-tracking
--prefix=/usr
--exec-prefix=/usr
--bindir=/usr/bin
--sbindir=/usr/sbin
--sysconfdir=/etc
--datadir=/usr/share
--includedir=/usr/include
--libdir=/usr/lib64
--libexecdir=/usr/libexec
--localstatedir=/var
--sharedstatedir=/var/lib
--mandir=/usr/share/man
--infodir=/usr/share/info
--enable-fuse
--enable-pixman
--enable-painter
--enable-vsock
--enable-ipv6
--with-socketdir=/run/xrdp
--with-imlib2
build_alias=x86_64-redhat-linux-gnu
host_alias=x86_64-redhat-linux-gnu
CC=gcc
CFLAGS=-O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -march=x86-64-v2 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection
LDFLAGS=-Wl,-z,relro -Wl,--as-needed -Wl,-z,now -specs=/usr/lib/rpm/redhat/redhat-hardened-ld -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1
CXX=g++
CXXFLAGS=-O2 -flto=auto -ffat-lto-objects -fexceptions -g -grecord-gcc-switches -pipe -Wall -Werror=format-security -Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 -fstack-protector-strong -specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -march=x86-64-v2 -mtune=generic -fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection
LT_SYS_LIBRARY_PATH=/usr/lib64:
PKG_CONFIG_PATH=:/usr/lib64/pkgconfig:/usr/share/pkgconfig
Compiled with OpenSSL 3.0.7 1 Nov 2022
Operating system & version
Almalinux 9
Installation method
dnf / apt / zypper / pkg / etc
Which backend do you use?
xvnc
What desktop environment do you use?
xfce
Environment xrdp running on
vm
What's your client?
No response
Area(s) with issue?
No response
Steps to reproduce
Set max_bpp = 24 and restart. The failure is resolved/worked around by resetting max_bpp to 32.
I forget why we had tuned this on centos 7 + an older xrdp. This setting worked with 0.9.25.
In the MacOS RDP client, the following is what's configured for display
✔️ Expected Behavior
Successful login with reduced color depth. The logs indicated this would occur but the result was a failure.
[2024-06-14T14:15:39.594+0000] [WARN ] Client requested 32 bpp color depth, but the server configuration is limited to 24 bpp. Downgrading the color depth to 24 bits-per-pixel.
❌ Actual Behavior
The above screenshot was from yesterday, the attached logs both working and failure with only the change to ^^ are attached below.
xrdp-failure.txt
xrdp-success.txt
Anything else?
We have also tuned the following settings in addition to the one mentioned above but do not expect them to have any impact on this.
- certificate
- key
- userwindowmanager =
.xsession - defaultwindowmanager =
/bin/xfce4-session - IdleTimeLimit =
86400 - DisconnectTimeLimit =
86400
More than anything this seemed odd to us and wanted to provide the feedback. We have worked around/resolved the issue for now by tuning max_bpp to 32 when using 0.10.0 and things seem to be stable so far.