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[src/trunk]: src/sys Move the MI parts of KASAN into kern/subr_asan.c. This f...
details: https://anonhg.NetBSD.org/src/rev/56a91fa82b4c
branches: trunk
changeset: 445498:56a91fa82b4c
user: maxv <maxv%NetBSD.org@localhost>
date: Wed Oct 31 06:26:25 2018 +0000
description:
Move the MI parts of KASAN into kern/subr_asan.c. This file includes
machine/asan.h, which contains the MD functions. We use an include rather
than a plain C file, because we want GCC to optimize/inline some functions
into one single block.
The amd64 MD parts of KASAN are moved accordingly.
The naming convention we use is:
kasan_*
a generic kasan object, declared in subr_asan.c
kasan_md_*
an MD kasan object, declared in machine/asan.h, and used
in subr_asan.c
__md_*
an MD object, declared in machine/asan.h, and not used
outside
Overall this makes it easier to add KASAN support on more architectures.
Discussed with several people.
diffstat:
sys/arch/amd64/amd64/asan.c | 725 -------------------------------------
sys/arch/amd64/amd64/machdep.c | 9 +-
sys/arch/amd64/conf/Makefile.amd64 | 4 +-
sys/arch/amd64/conf/files.amd64 | 3 +-
sys/arch/amd64/include/Makefile | 4 +-
sys/arch/amd64/include/asan.h | 221 +++++++++++
sys/arch/x86/x86/pmap.c | 6 +-
sys/kern/files.kern | 3 +-
sys/kern/subr_asan.c | 536 +++++++++++++++++++++++++++
sys/sys/asan.h | 7 +-
10 files changed, 777 insertions(+), 741 deletions(-)
diffs (truncated from 1659 to 300 lines):
diff -r 42ffc96a2903 -r 56a91fa82b4c sys/arch/amd64/amd64/asan.c
--- a/sys/arch/amd64/amd64/asan.c Wed Oct 31 06:04:48 2018 +0000
+++ /dev/null Thu Jan 01 00:00:00 1970 +0000
@@ -1,725 +0,0 @@
-/* $NetBSD: asan.c,v 1.10 2018/10/27 06:35:54 maxv Exp $ */
-
-/*
- * Copyright (c) 2018 The NetBSD Foundation, Inc.
- * All rights reserved.
- *
- * This code is derived from software contributed to The NetBSD Foundation
- * by Maxime Villard, and Siddharth Muralee.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
- * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
- * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
- * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
- * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
- * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
- * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
- * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
- * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
- * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- */
-
-#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: asan.c,v 1.10 2018/10/27 06:35:54 maxv Exp $");
-
-#include <sys/param.h>
-#include <sys/device.h>
-#include <sys/kernel.h>
-#include <sys/module.h>
-#include <sys/param.h>
-#include <sys/conf.h>
-#include <sys/systm.h>
-#include <sys/types.h>
-#include <sys/ksyms.h>
-#include <sys/asan.h>
-
-#include <uvm/uvm.h>
-#include <amd64/pmap.h>
-#include <amd64/vmparam.h>
-
-#define VIRTUAL_SHIFT 47 /* 48bit address space, cut half */
-#define CANONICAL_BASE 0xFFFF800000000000
-
-#define KASAN_SHADOW_SCALE_SHIFT 3
-#define KASAN_SHADOW_SCALE_SIZE (1UL << KASAN_SHADOW_SCALE_SHIFT)
-#define KASAN_SHADOW_MASK (KASAN_SHADOW_SCALE_SIZE - 1)
-
-#define KASAN_SHADOW_SIZE (1ULL << (VIRTUAL_SHIFT - KASAN_SHADOW_SCALE_SHIFT))
-#define KASAN_SHADOW_START (VA_SIGN_NEG((L4_SLOT_KASAN * NBPD_L4)))
-#define KASAN_SHADOW_END (KASAN_SHADOW_START + KASAN_SHADOW_SIZE)
-
-#define __RET_ADDR (unsigned long)__builtin_return_address(0)
-
-void kasan_softint(struct lwp *);
-void kasan_shadow_map(void *, size_t);
-void kasan_early_init(void);
-void kasan_init(void);
-
-static bool kasan_enabled __read_mostly = false;
-
-static inline int8_t *kasan_addr_to_shad(const void *addr)
-{
- vaddr_t va = (vaddr_t)addr;
- return (int8_t *)(KASAN_SHADOW_START +
- ((va - CANONICAL_BASE) >> KASAN_SHADOW_SCALE_SHIFT));
-}
-
-static __always_inline bool
-kasan_unsupported(vaddr_t addr)
-{
- return (addr >= (vaddr_t)PTE_BASE &&
- addr < ((vaddr_t)PTE_BASE + NBPD_L4));
-}
-
-/* -------------------------------------------------------------------------- */
-
-static bool kasan_early __read_mostly = true;
-static uint8_t earlypages[8 * PAGE_SIZE] __aligned(PAGE_SIZE);
-static size_t earlytaken = 0;
-
-static paddr_t
-kasan_early_palloc(void)
-{
- paddr_t ret;
-
- KASSERT(earlytaken < 8);
-
- ret = (paddr_t)(&earlypages[0] + earlytaken * PAGE_SIZE);
- earlytaken++;
-
- ret -= KERNBASE;
-
- return ret;
-}
-
-static paddr_t
-kasan_palloc(void)
-{
- paddr_t pa;
-
- if (__predict_false(kasan_early))
- pa = kasan_early_palloc();
- else
- pa = pmap_get_physpage();
-
- return pa;
-}
-
-static void
-kasan_shadow_map_page(vaddr_t va)
-{
- paddr_t pa;
-
- if (!pmap_valid_entry(L4_BASE[pl4_i(va)])) {
- pa = kasan_palloc();
- L4_BASE[pl4_i(va)] = pa | PG_KW | pmap_pg_nx | PG_V;
- }
- if (!pmap_valid_entry(L3_BASE[pl3_i(va)])) {
- pa = kasan_palloc();
- L3_BASE[pl3_i(va)] = pa | PG_KW | pmap_pg_nx | PG_V;
- }
- if (!pmap_valid_entry(L2_BASE[pl2_i(va)])) {
- pa = kasan_palloc();
- L2_BASE[pl2_i(va)] = pa | PG_KW | pmap_pg_nx | PG_V;
- }
- if (!pmap_valid_entry(L1_BASE[pl1_i(va)])) {
- pa = kasan_palloc();
- L1_BASE[pl1_i(va)] = pa | PG_KW | pmap_pg_g | pmap_pg_nx | PG_V;
- }
-}
-
-/*
- * Allocate the necessary stuff in the shadow, so that we can monitor the
- * passed area.
- */
-void
-kasan_shadow_map(void *addr, size_t size)
-{
- size_t sz, npages, i;
- vaddr_t sva, eva;
-
- KASSERT((vaddr_t)addr % KASAN_SHADOW_SCALE_SIZE == 0);
-
- sz = roundup(size, KASAN_SHADOW_SCALE_SIZE) / KASAN_SHADOW_SCALE_SIZE;
-
- sva = (vaddr_t)kasan_addr_to_shad(addr);
- eva = (vaddr_t)kasan_addr_to_shad(addr) + sz;
-
- sva = rounddown(sva, PAGE_SIZE);
- eva = roundup(eva, PAGE_SIZE);
-
- npages = (eva - sva) / PAGE_SIZE;
-
- KASSERT(sva >= KASAN_SHADOW_START && eva < KASAN_SHADOW_END);
-
- for (i = 0; i < npages; i++) {
- kasan_shadow_map_page(sva + i * PAGE_SIZE);
- }
-}
-
-/* -------------------------------------------------------------------------- */
-
-#ifdef __HAVE_PCPU_AREA
-#error "PCPU area not allowed with KASAN"
-#endif
-#ifdef __HAVE_DIRECT_MAP
-#error "DMAP not allowed with KASAN"
-#endif
-
-static void
-kasan_ctors(void)
-{
- extern uint64_t __CTOR_LIST__, __CTOR_END__;
- size_t nentries, i;
- uint64_t *ptr;
-
- nentries = ((size_t)&__CTOR_END__ - (size_t)&__CTOR_LIST__) /
- sizeof(uintptr_t);
-
- ptr = &__CTOR_LIST__;
- for (i = 0; i < nentries; i++) {
- void (*func)(void);
-
- func = (void *)(*ptr);
- (*func)();
-
- ptr++;
- }
-}
-
-/*
- * Map only the current stack. We will map the rest in kasan_init.
- */
-void
-kasan_early_init(void)
-{
- extern vaddr_t lwp0uarea;
-
- kasan_shadow_map((void *)lwp0uarea, USPACE);
- kasan_early = false;
-}
-
-/*
- * Create the shadow mapping. We don't create the 'User' area, because we
- * exclude it from the monitoring. The 'Main' area is created dynamically
- * in pmap_growkernel.
- */
-void
-kasan_init(void)
-{
- extern struct bootspace bootspace;
- size_t i;
-
- CTASSERT((KASAN_SHADOW_SIZE / NBPD_L4) == NL4_SLOT_KASAN);
-
- /* Kernel. */
- for (i = 0; i < BTSPACE_NSEGS; i++) {
- if (bootspace.segs[i].type == BTSEG_NONE) {
- continue;
- }
- kasan_shadow_map((void *)bootspace.segs[i].va,
- bootspace.segs[i].sz);
- }
-
- /* Boot region. */
- kasan_shadow_map((void *)bootspace.boot.va, bootspace.boot.sz);
-
- /* Module map. */
- kasan_shadow_map((void *)bootspace.smodule,
- (size_t)(bootspace.emodule - bootspace.smodule));
-
- /* The bootstrap spare va. */
- kasan_shadow_map((void *)bootspace.spareva, PAGE_SIZE);
-
- kasan_enabled = true;
-
- /* Call the ASAN constructors. */
- kasan_ctors();
-}
-
-/* -------------------------------------------------------------------------- */
-
-static inline bool
-kasan_unwind_end(const char *name)
-{
- if (!strcmp(name, "syscall") ||
- !strcmp(name, "handle_syscall") ||
- !strncmp(name, "Xintr", 5) ||
- !strncmp(name, "Xhandle", 7) ||
- !strncmp(name, "Xresume", 7) ||
- !strncmp(name, "Xstray", 6) ||
- !strncmp(name, "Xhold", 5) ||
- !strncmp(name, "Xrecurse", 8) ||
- !strcmp(name, "Xdoreti") ||
- !strncmp(name, "Xsoft", 5)) {
- return true;
- }
-
- return false;
-}
-
-static void
-kasan_unwind(void)
-{
- uint64_t *rbp, rip;
- const char *mod;
- const char *sym;
- size_t nsym;
- int error;
-
- rbp = (uint64_t *)__builtin_frame_address(0);
- nsym = 0;
-
- while (1) {
- /* 8(%rbp) contains the saved %rip. */
- rip = *(rbp + 1);
-
- if (rip < KERNBASE) {
- break;
- }
- error = ksyms_getname(&mod, &sym, (vaddr_t)rip, KSYMS_PROC);
- if (error) {
- break;
- }
- printf("#%zu %p in %s <%s>\n", nsym, (void *)rip, sym, mod);
- if (kasan_unwind_end(sym)) {
- break;
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