diff options
author | Konstantin Kostiuk <kkostiuk@redhat.com> | 2023-03-03 21:20:08 +0200 |
---|---|---|
committer | Konstantin Kostiuk <kkostiuk@redhat.com> | 2023-03-08 18:23:40 +0200 |
commit | 07ce178a2b0768eb9e712bb5ad0cf6dc7fcf0158 (patch) | |
tree | 50e4290ed02fc22bbcce4b02519db1f40a6e84a9 /qga | |
parent | 88288c2a51faa7c795f053fc8b31b1c16ff804c5 (diff) | |
download | qemu-07ce178a2b0768eb9e712bb5ad0cf6dc7fcf0158.zip qemu-07ce178a2b0768eb9e712bb5ad0cf6dc7fcf0158.tar.gz qemu-07ce178a2b0768eb9e712bb5ad0cf6dc7fcf0158.tar.bz2 |
qga/win32: Use rundll for VSS installation
The custom action uses cmd.exe to run VSS Service installation
and removal which causes an interactive command shell to spawn.
This shell can be used to execute any commands as a SYSTEM user.
Even if call qemu-ga.exe directly the interactive command shell
will be spawned as qemu-ga.exe is a console application and used
by users from the console as well as a service.
As VSS Service runs from DLL which contains the installer and
uninstaller code, it can be run directly by rundll32.exe without
any interactive command shell.
Add specific entry points for rundll which is just a wrapper
for COMRegister/COMUnregister functions with proper arguments.
resolves: https://bugzilla.redhat.com/show_bug.cgi?id=2167423
fixes: CVE-2023-0664 (part 2 of 2)
Signed-off-by: Konstantin Kostiuk <kkostiuk@redhat.com>
Reviewed-by: Yan Vugenfirer <yvugenfi@redhat.com>
Reported-by: Brian Wiltse <brian.wiltse@live.com>
Diffstat (limited to 'qga')
-rw-r--r-- | qga/installer/qemu-ga.wxs | 10 | ||||
-rw-r--r-- | qga/vss-win32/install.cpp | 9 | ||||
-rw-r--r-- | qga/vss-win32/qga-vss.def | 2 |
3 files changed, 16 insertions, 5 deletions
diff --git a/qga/installer/qemu-ga.wxs b/qga/installer/qemu-ga.wxs index feb629e..46ae9e7 100644 --- a/qga/installer/qemu-ga.wxs +++ b/qga/installer/qemu-ga.wxs @@ -127,22 +127,22 @@ </Directory> </Directory> - <Property Id="cmd" Value="cmd.exe"/> + <Property Id="rundll" Value="rundll32.exe"/> <Property Id="REINSTALLMODE" Value="amus"/> <?ifdef var.InstallVss?> <CustomAction Id="RegisterCom" - ExeCommand='/c "[qemu_ga_directory]qemu-ga.exe" -s vss-install' + ExeCommand='"[qemu_ga_directory]qga-vss.dll",DLLCOMRegister' Execute="deferred" - Property="cmd" + Property="rundll" Impersonate="no" Return="check" > </CustomAction> <CustomAction Id="UnRegisterCom" - ExeCommand='/c "[qemu_ga_directory]qemu-ga.exe" -s vss-uninstall' + ExeCommand='"[qemu_ga_directory]qga-vss.dll",DLLCOMUnregister' Execute="deferred" - Property="cmd" + Property="rundll" Impersonate="no" Return="check" > diff --git a/qga/vss-win32/install.cpp b/qga/vss-win32/install.cpp index b57508f..68662a6 100644 --- a/qga/vss-win32/install.cpp +++ b/qga/vss-win32/install.cpp @@ -357,6 +357,15 @@ out: return hr; } +STDAPI_(void) CALLBACK DLLCOMRegister(HWND, HINSTANCE, LPSTR, int) +{ + COMRegister(); +} + +STDAPI_(void) CALLBACK DLLCOMUnregister(HWND, HINSTANCE, LPSTR, int) +{ + COMUnregister(); +} static BOOL CreateRegistryKey(LPCTSTR key, LPCTSTR value, LPCTSTR data) { diff --git a/qga/vss-win32/qga-vss.def b/qga/vss-win32/qga-vss.def index 927782c..ee97a81 100644 --- a/qga/vss-win32/qga-vss.def +++ b/qga/vss-win32/qga-vss.def @@ -1,6 +1,8 @@ LIBRARY "QGA-PROVIDER.DLL" EXPORTS + DLLCOMRegister + DLLCOMUnregister COMRegister PRIVATE COMUnregister PRIVATE DllCanUnloadNow PRIVATE |