Re: su: Permission denied, (Ignored)

["Ben Hutchings" <ben.hutchings@businesswebsoftware.com>]

martin f krafft wrote:
> I have just encountered a weird message by /bin/su:
>
> master:/tmp# su -c id collector         
> su: Permission denied
> (Ignored)
> uid=200(collector) gid=200(collector) groups=200(collector)
>
> root su's to the collector user (pam_rootok allows this), and the
> command is executed. But where do the messages come from.
>
> strace says:
>
> [...]
> stat64("/root", {st_mode=S_IFDIR|0700, st_size=116, ...}) = 0
> stat64(".", 0xbffffa00)                 = -1 EACCES (Permission denied)
> brk(0)                                  = 0x80ec000
> brk(0x80ee000)                          = 0x80ee000
> getcwd("/root", 4096)                   = 6
> getpid()                                = 15728
> getppid()                               = 15727
> stat64(".", 0xbffffa30)                 = -1 EACCES (Permission denied)
<snip>
> The failing call seems to be a stat of the CWD, which is /tmp,
<snip>

The cwd here is /root (though I don't see why) and collector presumably 
doesn't have execute permission on /root so it can't even look up ".".

Ben.