On Saturday 11 Aug 2012, Raakesh kumar wrote: > I have reinstalled ubuntu again as going in recovery mode and doing > those changes didn't work for me. > @Balwinder Sir, I know i had made a mistake by doing so. But i was > just doing a kind of experiment but without properly surfing about > that... > > Okay.. just to ask, Can you please tell me what actually happened to > my system when i changed the permission of /etc directory? Why my > system done into an inconsistent state? While as much theory i have > read during my engineering about OSs, i hadn't done anything > special/severe in that..
There are files and directories in /etc that need specific permissions. Hell, there are files and directories everywhere that need those permissions. Off the top of my head, a few /etc-related permissions: Sub-directories: 0755 or similar. If you don't have those on (e.g.) pam.d, apache2, your servers won't work -- the files inside those directories will not be accessible. Files: passwd needs at least 444, because it has to be world readable. shadow needs to be 600 or similar, because it /shouldn't/ be world- readable; however, I don't know if any app enforces /etc/shadow permissions. Scripts and executables: At the very least, scripts in /etc/init.d need to be 755 or equivalent. If they aren't, your system will probably die a horrible death when trying to boot. Special files like the one you found: sudo will fail if sudoers is world readable, because it's paranoid about security. So you can have two types of problems related to file permissions: 1. Truncated permissions on the file (directory), because of which the system is unable to use the file for its intended purpose. 2. Extra permissions on a file, because of which an application that uses the file determines that it is insecure and refuses to use it. You saw the effect of the latter; if you'd continued you'd probably have seen the effects of the former too. /me shakes his head... Nautilus se sara /etc ka permission change kar diya... what will these kids think of next? Regards, -- Raj -- Raj Mathur || r...@kandalaya.org || GPG: http://otheronepercent.blogspot.com || http://kandalaya.org || CC68 It is the mind that moves || http://schizoid.in || D17F _______________________________________________ Ilugd mailing list Ilugd@lists.linux-delhi.org http://frodo.hserus.net/mailman/listinfo/ilugd
