Date: Tue, 01 Sep 1998 19:21:07 -0700 From: John Polstra <jdp@polstra.com> To: Bruce Evans <bde@zeta.org.au> Cc: reilly@zeta.org.au, current@FreeBSD.ORG Subject: Re: ELF binaries size Message-ID: <199809020221.TAA17213@austin.polstra.com> In-Reply-To: Your message of "Wed, 02 Sep 1998 12:14:40 %2B1000." <199809020214.MAA20550@godzilla.zeta.org.au>
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> I think it implies that elf wastes a full page of memory (the space > between the ':'s above) most of the time (unless the ':'s are on a > page boundary), while aout only wastes an average of half a page > (the space between the text ':' and the end of the page). But a.out has a repeat of the same situation at the juncture of data and bss, and ELF does not. > >> Is this a security problem? > > > >I don't think so. Do you? > > Maybe if text is supposed to be unreadable. The system would have > to clear the part of the first data page before the ':' to prevent > leakage. FreeBSD doesn't seem to do this. It's moot on the i386, if I remember correctly. Doesn't execute permission imply read permission on the i386? Also, how does it enhance security to prevent a program from reading its own text segment? If a program doesn't want to read its text segment then it should simply ... not read it. :-) John To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message
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