Messages in this thread | | | From | "H. Peter Anvin" <> | Subject | Re: Linux 2.2.18pre21 | Date | 16 Nov 2000 22:40:00 -0800 |
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Followup to: <20001117003000.B2918@wire.cadcamlab.org> By author: Peter Samuelson <peter@cadcamlab.org> In newsgroup: linux.dev.kernel > > > [jesse] > > 1. Your server closes all open directory file descriptors and chroots. > > 2. Someone manages to run some exploit code in your process space which-- > > mkdir("foo") > chroot("foo")
BUG: you *MUST* chdir() into the chroot jail before it does you any good at all!
I usually recommend:
mkdir("foo"); chdir("foo"); chroot(".");
> Bottom line: once you are in the chroot jail, you must drop root > privileges, or you defeat the purpose. Security-conscious coders know > this; it's not Linux-specific behavior or anything.
Indeed. They also know the above.
-hpa -- <hpa@transmeta.com> at work, <hpa@zytor.com> in private! "Unix gives you enough rope to shoot yourself in the foot." http://www.zytor.com/~hpa/puzzle.txt - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org Please read the FAQ at http://www.tux.org/lkml/
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