Re: nfsd-ganesha allows anyone to call into DBUS?

[Siddharth Sharma <siddharth () redhat com>]

Hi,

Which version of nfs-ganesha did you use ? Can you be more specific
I tried to reproduce this quite a lot of times in my testing environment
But I always get 

~]$  dbus-send --print-reply --system --dest=org.ganesha.nfsd  /org/ganesha/nfsd/ExportMgr 
org.ganesha.nfsd.exportmgr.AddExport  string:$GANESHA_DIR/exports/export.$VOL.conf 
string:"EXPORT(Path=/$SERV_MALICIOUS_CONTENT)"
Error org.freedesktop.DBus.Error.AccessDenied: Rejected send message, 1 matched rules; type="method_call", 
sender=":1.159" (uid=1000 pid=3852 comm="dbus-send --print-reply --system --dest=org.ganesh") 

anything you did differently ?
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Siddharth Sharma / Red Hat Product Security / Key ID : 0xD9F6489A      
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----- Original Message -----
From: "Sebastian Krahmer" <krahmer () suse com>
To: oss-security () lists openwall com
Cc: matt () linuxbox com, "philippe deniel" <philippe.deniel () cea fr>
Sent: Monday, September 12, 2016 3:23:53 PM
Subject: [oss-security] nfsd-ganesha allows anyone to call into DBUS?

Hi

The nfs-ganesha (userspace nfsd) offers a dbus API to control/admin
the nfsd via cmdline tools and some qt+python code.

The default dbus config seems to allow anyone to connect to
it and invoke methods. The code at least does not check any polkit
authorizations or dbus sender (at a first look). Am I missing something? If I dont,
the DBUS API should be declared experimental and disabled by default,
since there are some methods which would allow users to gain root.

https://github.com/nfs-ganesha/nfs-ganesha/
https://github.com/nfs-ganesha/nfs-ganesha/wiki/Dbusinterface

Sebastian

-- 

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