freebsd-skq/lib/libkvm/kvm_minidump_amd64.c
ngie a9f56210b8 Fix up pointer issues with lib/libkvm
In particular,
- avoid dereferencing NULL pointers
- test pointers against NULL, not 0
- test for errout == NULL in the top-level functions (kvm_open, kvm_openfiles,
  kvm_open2, etc)
- Replace a realloc and free on failure with reallocf

Found with: devel/cocchinelle

Differential Revision: https://reviews.freebsd.org/D5954
MFC after: 1 week
Reviewed by: jhb
Sponsored by: EMC / Isilon Storage Division
2016-04-22 18:05:34 +00:00

322 lines
8.9 KiB
C

/*-
* Copyright (c) 2006 Peter Wemm
*
* 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 AUTHOR 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 AUTHOR 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>
__FBSDID("$FreeBSD$");
/*
* AMD64 machine dependent routines for kvm and minidumps.
*/
#include <sys/param.h>
#include <sys/endian.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <kvm.h>
#include "../../sys/amd64/include/minidump.h"
#include <limits.h>
#include "kvm_private.h"
#include "kvm_amd64.h"
#define amd64_round_page(x) roundup2((kvaddr_t)(x), AMD64_PAGE_SIZE)
struct vmstate {
struct minidumphdr hdr;
struct hpt hpt;
amd64_pte_t *page_map;
};
static int
_amd64_minidump_probe(kvm_t *kd)
{
return (_kvm_probe_elf_kernel(kd, ELFCLASS64, EM_X86_64) &&
_kvm_is_minidump(kd));
}
static void
_amd64_minidump_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
_kvm_hpt_free(&vm->hpt);
if (vm->page_map)
free(vm->page_map);
free(vm);
kd->vmst = NULL;
}
static int
_amd64_minidump_initvtop(kvm_t *kd)
{
struct vmstate *vmst;
uint64_t *bitmap;
off_t off;
vmst = _kvm_malloc(kd, sizeof(*vmst));
if (vmst == NULL) {
_kvm_err(kd, kd->program, "cannot allocate vm");
return (-1);
}
kd->vmst = vmst;
if (pread(kd->pmfd, &vmst->hdr, sizeof(vmst->hdr), 0) !=
sizeof(vmst->hdr)) {
_kvm_err(kd, kd->program, "cannot read dump header");
return (-1);
}
if (strncmp(MINIDUMP_MAGIC, vmst->hdr.magic, sizeof(vmst->hdr.magic)) != 0) {
_kvm_err(kd, kd->program, "not a minidump for this platform");
return (-1);
}
/*
* NB: amd64 minidump header is binary compatible between version 1
* and version 2; this may not be the case for the future versions.
*/
vmst->hdr.version = le32toh(vmst->hdr.version);
if (vmst->hdr.version != MINIDUMP_VERSION && vmst->hdr.version != 1) {
_kvm_err(kd, kd->program, "wrong minidump version. expected %d got %d",
MINIDUMP_VERSION, vmst->hdr.version);
return (-1);
}
vmst->hdr.msgbufsize = le32toh(vmst->hdr.msgbufsize);
vmst->hdr.bitmapsize = le32toh(vmst->hdr.bitmapsize);
vmst->hdr.pmapsize = le32toh(vmst->hdr.pmapsize);
vmst->hdr.kernbase = le64toh(vmst->hdr.kernbase);
vmst->hdr.dmapbase = le64toh(vmst->hdr.dmapbase);
vmst->hdr.dmapend = le64toh(vmst->hdr.dmapend);
/* Skip header and msgbuf */
off = AMD64_PAGE_SIZE + amd64_round_page(vmst->hdr.msgbufsize);
bitmap = _kvm_malloc(kd, vmst->hdr.bitmapsize);
if (bitmap == NULL) {
_kvm_err(kd, kd->program, "cannot allocate %d bytes for bitmap", vmst->hdr.bitmapsize);
return (-1);
}
if (pread(kd->pmfd, bitmap, vmst->hdr.bitmapsize, off) !=
(ssize_t)vmst->hdr.bitmapsize) {
_kvm_err(kd, kd->program, "cannot read %d bytes for page bitmap", vmst->hdr.bitmapsize);
free(bitmap);
return (-1);
}
off += amd64_round_page(vmst->hdr.bitmapsize);
vmst->page_map = _kvm_malloc(kd, vmst->hdr.pmapsize);
if (vmst->page_map == NULL) {
_kvm_err(kd, kd->program, "cannot allocate %d bytes for page_map", vmst->hdr.pmapsize);
free(bitmap);
return (-1);
}
if (pread(kd->pmfd, vmst->page_map, vmst->hdr.pmapsize, off) !=
(ssize_t)vmst->hdr.pmapsize) {
_kvm_err(kd, kd->program, "cannot read %d bytes for page_map", vmst->hdr.pmapsize);
free(bitmap);
return (-1);
}
off += vmst->hdr.pmapsize;
/* build physical address hash table for sparse pages */
_kvm_hpt_init(kd, &vmst->hpt, bitmap, vmst->hdr.bitmapsize, off,
AMD64_PAGE_SIZE, sizeof(*bitmap));
free(bitmap);
return (0);
}
static int
_amd64_minidump_vatop_v1(kvm_t *kd, kvaddr_t va, off_t *pa)
{
struct vmstate *vm;
amd64_physaddr_t offset;
amd64_pte_t pte;
kvaddr_t pteindex;
amd64_physaddr_t a;
off_t ofs;
vm = kd->vmst;
offset = va & AMD64_PAGE_MASK;
if (va >= vm->hdr.kernbase) {
pteindex = (va - vm->hdr.kernbase) >> AMD64_PAGE_SHIFT;
if (pteindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
goto invalid;
pte = le64toh(vm->page_map[pteindex]);
if ((pte & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop_v1: pte not valid");
goto invalid;
}
a = pte & AMD64_PG_FRAME;
ofs = _kvm_hpt_find(&vm->hpt, a);
if (ofs == -1) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop_v1: physical address 0x%jx not in minidump",
(uintmax_t)a);
goto invalid;
}
*pa = ofs + offset;
return (AMD64_PAGE_SIZE - offset);
} else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
ofs = _kvm_hpt_find(&vm->hpt, a);
if (ofs == -1) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop_v1: direct map address 0x%jx not in minidump",
(uintmax_t)va);
goto invalid;
}
*pa = ofs + offset;
return (AMD64_PAGE_SIZE - offset);
} else {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop_v1: virtual address 0x%jx not minidumped",
(uintmax_t)va);
goto invalid;
}
invalid:
_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
return (0);
}
static int
_amd64_minidump_vatop(kvm_t *kd, kvaddr_t va, off_t *pa)
{
amd64_pte_t pt[AMD64_NPTEPG];
struct vmstate *vm;
amd64_physaddr_t offset;
amd64_pde_t pde;
amd64_pte_t pte;
kvaddr_t pteindex;
kvaddr_t pdeindex;
amd64_physaddr_t a;
off_t ofs;
vm = kd->vmst;
offset = va & AMD64_PAGE_MASK;
if (va >= vm->hdr.kernbase) {
pdeindex = (va - vm->hdr.kernbase) >> AMD64_PDRSHIFT;
if (pdeindex >= vm->hdr.pmapsize / sizeof(*vm->page_map))
goto invalid;
pde = le64toh(vm->page_map[pdeindex]);
if ((pde & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop: pde not valid");
goto invalid;
}
if ((pde & AMD64_PG_PS) == 0) {
a = pde & AMD64_PG_FRAME;
ofs = _kvm_hpt_find(&vm->hpt, a);
if (ofs == -1) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop: pt physical address 0x%jx not in minidump",
(uintmax_t)a);
goto invalid;
}
/* TODO: Just read the single PTE */
if (pread(kd->pmfd, &pt, AMD64_PAGE_SIZE, ofs) !=
AMD64_PAGE_SIZE) {
_kvm_err(kd, kd->program,
"cannot read %d bytes for page table",
AMD64_PAGE_SIZE);
return (-1);
}
pteindex = (va >> AMD64_PAGE_SHIFT) &
(AMD64_NPTEPG - 1);
pte = le64toh(pt[pteindex]);
if ((pte & AMD64_PG_V) == 0) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop: pte not valid");
goto invalid;
}
a = pte & AMD64_PG_FRAME;
} else {
a = pde & AMD64_PG_PS_FRAME;
a += (va & AMD64_PDRMASK) ^ offset;
}
ofs = _kvm_hpt_find(&vm->hpt, a);
if (ofs == -1) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop: physical address 0x%jx not in minidump",
(uintmax_t)a);
goto invalid;
}
*pa = ofs + offset;
return (AMD64_PAGE_SIZE - offset);
} else if (va >= vm->hdr.dmapbase && va < vm->hdr.dmapend) {
a = (va - vm->hdr.dmapbase) & ~AMD64_PAGE_MASK;
ofs = _kvm_hpt_find(&vm->hpt, a);
if (ofs == -1) {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop: direct map address 0x%jx not in minidump",
(uintmax_t)va);
goto invalid;
}
*pa = ofs + offset;
return (AMD64_PAGE_SIZE - offset);
} else {
_kvm_err(kd, kd->program,
"_amd64_minidump_vatop: virtual address 0x%jx not minidumped",
(uintmax_t)va);
goto invalid;
}
invalid:
_kvm_err(kd, 0, "invalid address (0x%jx)", (uintmax_t)va);
return (0);
}
static int
_amd64_minidump_kvatop(kvm_t *kd, kvaddr_t va, off_t *pa)
{
if (ISALIVE(kd)) {
_kvm_err(kd, 0,
"_amd64_minidump_kvatop called in live kernel!");
return (0);
}
if (((struct vmstate *)kd->vmst)->hdr.version == 1)
return (_amd64_minidump_vatop_v1(kd, va, pa));
else
return (_amd64_minidump_vatop(kd, va, pa));
}
struct kvm_arch kvm_amd64_minidump = {
.ka_probe = _amd64_minidump_probe,
.ka_initvtop = _amd64_minidump_initvtop,
.ka_freevtop = _amd64_minidump_freevtop,
.ka_kvatop = _amd64_minidump_kvatop,
.ka_native = _amd64_native,
};
KVM_ARCH(kvm_amd64_minidump);