oss-sec mailing list archives
Re: Re: [Security] [oss-security] Re: /proc infoleaks
From: Brad Spengler <spender () grsecurity net>
Date: Wed, 8 Sep 2010 07:47:31 -0400
I agree that distros also have to do some homework there, but there are things that we cant just do via init harden scripts. Take /proc/pid/stack. Other files like my prefered friend /proc/net/netlink gives info that allows exploitation-deluxe if you overwrite your socket destructor.
That's true too -- I was just talking about the ones mentioned in the original post. /proc/pid/stack goes away when you disable CONFIG_STACKTRACE btw, but the best solution going forward (as a lot of these and other infoleaks have been added recently through new features) is this: the internals of the kernel should be a black box to unprivileged processes. This needs to be considered by the people who write and approve these new features that push out all kinds of information via /proc and elsewhere. If it doesn't get considered before it goes into the kernel, then we have to play this game after the fact of staying compatible with apps that now depend on that behavior.
Sure. It was just a proposal since I felt nobody really cared about the low hanging fruits. It wont make your system rocket proof but it makes some head-scratching for exploit developers which is all you need if you make them stuck in doing that.
Be careful about assuming head-scratching -- if something can be worked around (like in the kallsyms case), it only takes one person. Everyone else can reuse that work without any head-scratching. -Brad
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Current thread:
- /proc infoleaks Sebastian Krahmer (Sep 07)
- Re: [Security] /proc infoleaks Andrew Morton (Sep 07)
- Re: [Security] /proc infoleaks Sebastian Krahmer (Sep 07)
- Re: Re: [Security] /proc infoleaks Marcus Meissner (Sep 07)
- Re: [Security] [oss-security] Re: /proc infoleaks Willy Tarreau (Sep 13)
- Re: [Security] /proc infoleaks Sebastian Krahmer (Sep 07)
- Re: Re: [Security] /proc infoleaks Jon Oberheide (Sep 07)
- Re: Re: [Security] /proc infoleaks Andrew Morton (Sep 07)
- Re: [Security] [oss-security] Re: /proc infoleaks Andrew Morton (Sep 07)
- Re: [Security] [oss-security] Re: /proc infoleaks Brad Spengler (Sep 07)
- Re: Re: [Security] [oss-security] Re: /proc infoleaks Sebastian Krahmer (Sep 07)
- Re: Re: [Security] [oss-security] Re: /proc infoleaks Brad Spengler (Sep 08)
- Re: [Security] /proc infoleaks Andrew Morton (Sep 07)
- Re: [Security] [oss-security] Re: /proc infoleaks Linus Torvalds (Sep 07)