head 1.2; access; symbols pkgsrc-2016Q4:1.1.0.4 pkgsrc-2016Q4-base:1.1 pkgsrc-2016Q3:1.1.0.2 pkgsrc-2016Q3-base:1.1; locks; strict; comment @# @; 1.2 date 2016.12.29.19.13.02; author wiz; state dead; branches; next 1.1; commitid kFYPk8EnajcmFUzz; 1.1 date 2016.09.08.15.41.01; author bouyer; state Exp; branches; next ; commitid c9X7FynnoqZn5vlz; desc @@ 1.2 log @Remove xenkernel and tools versions 3, 33, and 41. As discussed on pkgsrc-users. @ text @$NetBSD: patch-XSA-187-1,v 1.1 2016/09/08 15:41:01 bouyer Exp $ From: Andrew Cooper Subject: x86/shadow: Avoid overflowing sh_ctxt->seg_reg[] hvm_get_seg_reg() does not perform a range check on its input segment, calls hvm_get_segment_register() and writes straight into sh_ctxt->seg_reg[]. x86_seg_none is outside the bounds of sh_ctxt->seg_reg[], and will hit a BUG() in {vmx,svm}_get_segment_register(). HVM guests running with shadow paging can end up performing a virtual to linear translation with x86_seg_none. This is used for addresses which are already linear. However, none of this is a legitimate pagetable update, so fail the emulation in such a case. This is XSA-187 Reported-by: Andrew Cooper Signed-off-by: Andrew Cooper Reviewed-by: Tim Deegan --- xen/arch/x86/mm/shadow/common.c.orig +++ xen/arch/x86/mm/shadow/common.c @@@@ -140,9 +140,18 @@@@ static int hvm_translate_linear_addr( struct sh_emulate_ctxt *sh_ctxt, unsigned long *paddr) { - struct segment_register *reg = hvm_get_seg_reg(seg, sh_ctxt); + struct segment_register *reg; int okay; + /* + * Can arrive here with non-user segments. However, no such cirucmstance + * is part of a legitimate pagetable update, so fail the emulation. + */ + if ( !is_x86_user_segment(seg) ) + return X86EMUL_UNHANDLEABLE; + + reg = hvm_get_seg_reg(seg, sh_ctxt); + okay = hvm_virtual_to_linear_addr( seg, reg, offset, bytes, access_type, sh_ctxt->ctxt.addr_size, paddr); @ 1.1 log @Backport upstream patches for security issues: XSA-185: x86: Disallow L3 recursive pagetable for 32-bit PV guests XSA-187: x86 HVM: Overflow of sh_ctxt->seg_reg[] bump PKGREVISION @ text @d1 1 a1 1 $NetBSD: $ @