x86-64: Give vvars their own page
authorAndy Lutomirski <luto@MIT.EDU>
Sun, 5 Jun 2011 17:50:19 +0000 (13:50 -0400)
committerIngo Molnar <mingo@elte.hu>
Sun, 5 Jun 2011 19:30:32 +0000 (21:30 +0200)
commit9fd67b4ed0714ab718f1f9bd14c344af336a6df7
tree7dae7e978b68479b6ee316d92b81d703cee3a894
parent8b4777a4b50cb0c84c1152eac85d24415fb6ff7d
x86-64: Give vvars their own page

Move vvars out of the vsyscall page into their own page and mark
it NX.

Without this patch, an attacker who can force a daemon to call
some fixed address could wait until the time contains, say,
0xCD80, and then execute the current time.

Signed-off-by: Andy Lutomirski <luto@mit.edu>
Cc: Jesper Juhl <jj@chaosbits.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Arjan van de Ven <arjan@infradead.org>
Cc: Jan Beulich <JBeulich@novell.com>
Cc: richard -rw- weinberger <richard.weinberger@gmail.com>
Cc: Mikael Pettersson <mikpe@it.uu.se>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Louis Rilling <Louis.Rilling@kerlabs.com>
Cc: Valdis.Kletnieks@vt.edu
Cc: pageexec@freemail.hu
Link: http://lkml.kernel.org/r/b1460f81dc4463d66ea3f2b5ce240f58d48effec.1307292171.git.luto@mit.edu
Signed-off-by: Ingo Molnar <mingo@elte.hu>
arch/x86/include/asm/fixmap.h
arch/x86/include/asm/pgtable_types.h
arch/x86/include/asm/vvar.h
arch/x86/kernel/vmlinux.lds.S
arch/x86/kernel/vsyscall_64.c