/* * This source code is a part of coLinux source package. * * Dan Aloni <da-x@colinux.org>, 2004 (c) * * The code is licensed under the GPL. See the COPYING file at * the root directory. */ #include <colinux/common/common.h>#include <colinux/common/debug.h>#include <colinux/kernel/monitor.h>#include <colinux/os/kernel/alloc.h>#include "manager.h"#include "antinx.h"#include "defs.h"#include "utils.h"/* Workarrount for Intel P4 and Xeon, that's crashing with DEP/noexecute. *//* http://download.intel.com/design/Pentium4/specupdt/249199.htm: *//* N76  Changes to CR3 Register do not Fence Pending Instruction Page Walks. *//* http://download.intel.com/design/Pentium4/manuals/253668.htm: *//* 3.12 TRANSLATION LOOKASIDE BUFFERS (TLBS) */#define flush_tlb()							\	do {								\		unsigned int tmpreg;					\									\		__asm__ __volatile__(					\			"movl %%cr3, %0;              \n"		\			"movl %0, %%cr3;  # flush TLB \n"		\			: "=r" (tmpreg)					\			:: "memory");					\	} while (0)co_rc_t co_arch_anti_nx_init(co_monitor_t *mon){	co_archdep_monitor_t archdep;	co_archdep_manager_t marchdep;	co_rc_t rc;	bool_t pae_enabled;	co_pfn_t pfn, pfn_next;	unsigned long cr3;	unsigned char *page;	unsigned long long *ptes;	unsigned long vaddr;	archdep = mon->archdep;	marchdep = mon->manager->archdep;	vaddr = (unsigned long)mon->passage_page;	co_debug_lvl(misc, 11, "vaddr = %08lx", vaddr);	if (!(marchdep->caps[1] & (1 << CO_ARCH_AMD_FEATURE_NX))) {		co_debug("AMD's NX is not enabled");		return CO_RC(OK);	}	pae_enabled = co_is_pae_enabled();	if (!pae_enabled) {		co_debug("PAE is not enabled");		return CO_RC(OK);	}	cr3 = co_get_cr3();	co_debug_lvl(misc, 11, "cr3 = %08lx", cr3);	pfn = cr3 >> CO_ARCH_PAGE_SHIFT;	co_debug("pfn = %08lx", (long)pfn);	page = co_os_map(mon->manager, pfn);	if (!page) {		rc = CO_RC(ERROR);		goto out;	}	co_debug_lvl(misc, 11, "page = %p", page);	ptes = ((unsigned long long *)&(page[((cr3 & (~CO_ARCH_PAGE_MASK)) & ~0x1f)]));	co_debug_lvl(misc, 11, "ptes = %p", ptes);	pfn_next = ptes[vaddr >> CO_ARCH_PAE_PGD_SHIFT] >> CO_ARCH_PAGE_SHIFT;	co_debug_lvl(misc, 11, "pfn_next = %08lx", pfn_next);	co_os_unmap(mon->manager, page, pfn);	pfn = pfn_next;	page = co_os_map(mon->manager, pfn);	if (!page) {		rc = CO_RC(ERROR);		goto out;	}	co_debug_lvl(misc, 11, "page = %p", page);	ptes = (unsigned long long *)page;	ptes = &ptes[(vaddr & ~CO_ARCH_PAE_PGD_MASK) >> CO_ARCH_PAE_PMD_SHIFT];	co_debug_lvl(misc, 11, "ptes = %p", ptes);	if (!(*ptes & _PAGE_PSE)) {		pfn_next = (*ptes) >> CO_ARCH_PAGE_SHIFT;		co_debug_lvl(misc, 11, "pfn_next = %08lx", pfn_next);		co_os_unmap(mon->manager, page, pfn);		pfn = pfn_next;				page = co_os_map(mon->manager, pfn);		if (!page) {			rc = CO_RC(ERROR);			goto out;		}				co_debug_lvl(misc, 11, "page = %p", page);		ptes = (unsigned long long *)page;		ptes = &ptes[(vaddr & ~CO_ARCH_PAE_PMD_MASK) >> CO_ARCH_PAGE_SHIFT];		co_debug_lvl(misc, 11, "ptes = %p", ptes);	}	co_debug_lvl(misc, 11, "unmask page NX and flush tlb");	*ptes &= ~CO_ARCH_PAGE_NX;	flush_tlb();	archdep->fixed_pte = ptes;	archdep->fixed_page_table_pfn = pfn;	archdep->fixed_page_table_mapping = page;	archdep->antinx_enabled = PTRUE;	return CO_RC(OK);out:	return CO_RC(ERROR);}void co_arch_anti_nx_free(co_monitor_t *mon){	co_archdep_monitor_t archdep = mon->archdep;	if (!archdep->antinx_enabled)		return;	co_os_unmap(mon->manager, 		    archdep->fixed_page_table_mapping,		    archdep->fixed_page_table_pfn);	archdep->antinx_enabled = PFALSE;	}