Re: 2.6.25 Kernel - Problems with capabilities

[David <david@unsolicited.net>]

Mike Galbraith wrote:
> On Sat, 2008-04-19 at 19:43 +0100, David wrote:
>   
>> I'm wondering if anyone might be able to help with a capability problem 
>> I've noticed with .25 My ntp daemon will no longer run as any non-root 
>> user, and after some investigation it seems that calls to prctl() are 
>> failing.
>>
>> CONFIG_SECURITY_CAPABILITIES=y , so this should work?
>>
>> System is 32 bit x86 based on a venerable SuSE 9.1 distro.
>>
>> Full .config is attached.
>>
>> Thanks
>> David
>>
>>
>>     
>
> FWIW, ntpd runs just fine here as user ntp on both my P4 and Q6600 boxen
> with opensuse 10.3.
>
> marge:..tmp/linux-2.6.25 # grep SECUR .config
> CONFIG_EXT2_FS_SECURITY=y
> CONFIG_EXT3_FS_SECURITY=y
> CONFIG_EXT4DEV_FS_SECURITY=y
> CONFIG_SECURITY=y
> CONFIG_SECURITY_NETWORK=y
> CONFIG_SECURITY_NETWORK_XFRM=y
> CONFIG_SECURITY_CAPABILITIES=y
> CONFIG_SECURITY_FILE_CAPABILITIES=y
> CONFIG_SECURITY_DEFAULT_MMAP_MIN_ADDR=0
> # CONFIG_SECURITY_SELINUX is not set
> marge:..tmp/linux-2.6.25 # grep SECUR /xx
> CONFIG_EXT2_FS_SECURITY=y
> CONFIG_EXT3_FS_SECURITY=y
> CONFIG_REISERFS_FS_SECURITY=y
> # CONFIG_XFS_SECURITY is not set
> CONFIG_SECURITY=y
> CONFIG_SECURITY_NETWORK=y
> # CONFIG_SECURITY_NETWORK_XFRM is not set
> CONFIG_SECURITY_CAPABILITIES=y
> # CONFIG_SECURITY_FILE_CAPABILITIES is not set
> # CONFIG_SECURITY_ROOTPLUG is not set
> CONFIG_SECURITY_DEFAULT_MMAP_MIN_ADDR=0
>
> I notice I have CONFIG_SECURITY_FILE_CAPABILITIES set, and you don't.  I
> have not even the foggiest clue whether that has anything to do with the
> price of tea in china though :)
>   
I've just set

CONFIG_SECURITY_FILE_CAPABILITIES=y
CONFIG_SECURITY_NETWORK_XFRM=y

to no avail.. I still get


20 Apr 15:04:20 ntpd[15694]: cap_set_proc() failed to drop root 
privileges: Invalid argument

after rebuild & reboot. No massive deal, I'll just run ntpd as root for 
now, but there's definitely something funny going on.

Cheers
David