pam_ssh_agent_auth coredump on AMD64 (was Re: PAM modules)

[Mike Tancsa]

On 9/19/2011 2:00 PM, Mike Tancsa wrote:
> On 9/16/2011 3:10 PM, Corey Smith wrote:
>> On 09/16/2011 11:05 AM, Dag-Erling Smørgrav wrote:
>>>  My question is: which ones?
>>
>> security/pam_ssh_agent_auth
>>
>> It is BSD licensed and handy for sudo.
> 
> 
> Neato, I didnt know of this module for sudo!  However, with the default
> install on AMD64, I am getting coredump.

Actually, I tried the same setup on i386 and it seems to work just fine.
 However, on an AMD64 machine, sudo just coredumps.  Anyone running this
setup on amd64 ?

Running with -D9, normally it looks something like

% sudo -D9 su
sudo: settings: debug_level=9
sudo: settings: progname=sudo
sudo: settings: network_addrs=....
sudo: sudo_mode 1
sudo: policy plugin returns 1
sudo: command info: umask=022
sudo: command info: command=/usr/bin/su
sudo: command info: runas_uid=0
sudo: command info: runas_gid=0
sudo: command info: runas_groups=0,5
sudo: command info: closefrom=3
sudo: command info: set_utmp=true
sudo: command info: login_class=default

where as on amd64,

% sudo -D9 su
sudo: settings: debug_level=9
sudo: settings: progname=sudo
sudo: settings: network_addrs=....
sudo: sudo_mode 1
Segmentation fault

It seems to die in the call to

static int
policy_check(struct plugin_container *plugin, int argc, char * const argv[],
    char *env_add[], char **command_info[], char **argv_out[],
    char **user_env_out[])
{
    return plugin->u.policy->check_policy(argc, argv, env_add, command_info,
        argv_out, user_env_out);
}


I cant get it to coredump since its setuid.  Before I start adding more
debug printfs, does anyone have any suggestions as to what it might be ?


	---Mike


> 
> I added
> 
> 
>  # auth
>  auth           include         system
> -
> +auth           sufficient      /usr/local/lib/pam_ssh_agent_auth.so
> file=/etc/sudokeys debug
>  # account
>  account                include         system
> 
> to /usr/local/etc/pam.d/sudo
> 
> and added
> 
> --- sudoers.sample      2011-09-19 13:24:56.000000000 -0400
> +++ sudoers     2011-09-19 13:29:17.000000000 -0400
> @@ -62,6 +62,10 @@
>  ## Uncomment to enable special input methods.  Care should be taken as
>  ## this may allow users to subvert the command being run via sudo.
>  # Defaults env_keep += "XMODIFIERS GTK_IM_MODULE QT_IM_MODULE
> QT_IM_SWITCHER"
> +
> +Defaults env_keep += SSH_AUTH_SOCK
> +
> +
> 
> 
> I must be missing something obvious?
> 
> 	---Mike
> 
> 


-- 
-------------------
Mike Tancsa, tel +1 519 651 3400
Sentex Communications, mike at sentex.net
Providing Internet services since 1994 www.sentex.net
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