value the kernel calculated directly as we already read it with struct vnet. This will make kvm_vnet.c more resilent in case of possible kernel changes. Reviewed by: rwatson Approved by: re (kib)
237 lines
6.4 KiB
C
237 lines
6.4 KiB
C
/*-
|
|
* Copyright (c) 2009 Robert N. M. Watson
|
|
* Copyright (c) 2009 Bjoern A. Zeeb <bz@FreeBSD.org>
|
|
* All rights reserved.
|
|
*
|
|
* 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("$FreeBSD$");
|
|
|
|
#include <sys/param.h>
|
|
|
|
#define _WANT_PRISON
|
|
#define _WANT_UCRED
|
|
#define _WANT_VNET
|
|
|
|
#include <sys/_lock.h>
|
|
#include <sys/_mutex.h>
|
|
#include <sys/_task.h>
|
|
#include <sys/jail.h>
|
|
#include <sys/proc.h>
|
|
#include <sys/types.h>
|
|
|
|
#include <net/vnet.h>
|
|
|
|
#include <nlist.h>
|
|
#include <kvm.h>
|
|
#include <limits.h>
|
|
#include <stdlib.h>
|
|
#include <unistd.h>
|
|
|
|
#include "kvm_private.h"
|
|
|
|
/*
|
|
* Set up libkvm to handle virtual network stack symbols by selecting a
|
|
* starting pid.
|
|
*/
|
|
int
|
|
_kvm_vnet_selectpid(kvm_t *kd, pid_t pid)
|
|
{
|
|
struct proc proc;
|
|
struct thread td;
|
|
struct ucred cred;
|
|
struct prison prison;
|
|
struct vnet vnet;
|
|
struct nlist nl[] = {
|
|
/*
|
|
* Note: kvm_nlist strips the first '_' so add an extra one
|
|
* here to __{start,stop}_set_vnet.
|
|
*/
|
|
#define NLIST_START_VNET 0
|
|
{ .n_name = "___start_" VNET_SETNAME },
|
|
#define NLIST_STOP_VNET 1
|
|
{ .n_name = "___stop_" VNET_SETNAME },
|
|
#define NLIST_VNET_HEAD 2
|
|
{ .n_name = "vnet_head" },
|
|
#define NLIST_ALLPROC 3
|
|
{ .n_name = "allproc" },
|
|
#define NLIST_DUMPTID 4
|
|
{ .n_name = "dumptid" },
|
|
#define NLIST_PROC0 5
|
|
{ .n_name = "proc0" },
|
|
{ .n_name = NULL },
|
|
};
|
|
uintptr_t procp, tdp, credp;
|
|
lwpid_t dumptid;
|
|
|
|
/*
|
|
* Locate and cache locations of important symbols
|
|
* using the internal version of _kvm_nlist, turning
|
|
* off initialization to avoid recursion in case of
|
|
* unresolveable symbols.
|
|
*/
|
|
if (_kvm_nlist(kd, nl, 0) != 0) {
|
|
/*
|
|
* XXX-BZ: ___start_/___stop_VNET_SETNAME may fail.
|
|
* For now do not report an error here as we are called
|
|
* internally and in `void context' until we merge the
|
|
* functionality to optionally activate this into programs.
|
|
* By that time we can properly fail and let the callers
|
|
* handle the error.
|
|
*/
|
|
/* _kvm_err(kd, kd->program, "%s: no namelist", __func__); */
|
|
return (-1);
|
|
}
|
|
|
|
/*
|
|
* Auto-detect if this is a crashdump by reading dumptid.
|
|
*/
|
|
dumptid = 0;
|
|
if (nl[NLIST_DUMPTID].n_value) {
|
|
if (kvm_read(kd, nl[NLIST_DUMPTID].n_value, &dumptid,
|
|
sizeof(dumptid)) != sizeof(dumptid)) {
|
|
_kvm_err(kd, kd->program, "%s: dumptid", __func__);
|
|
return (-1);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* First, find the process for this pid. If we are workig on a dump,
|
|
* either locate the thread dumptid is refering to or proc0.
|
|
* Based on either, take the address of the ucred.
|
|
*/
|
|
credp = 0;
|
|
|
|
procp = nl[NLIST_ALLPROC].n_value;
|
|
#define VMCORE_VNET_OF_PROC0
|
|
#ifdef VMCORE_VNET_OF_PROC0
|
|
if (dumptid > 0) {
|
|
procp = nl[NLIST_PROC0].n_value;
|
|
pid = 0;
|
|
}
|
|
#endif
|
|
while (procp != 0) {
|
|
if (kvm_read(kd, procp, &proc, sizeof(proc)) != sizeof(proc)) {
|
|
_kvm_err(kd, kd->program, "%s: proc", __func__);
|
|
return (-1);
|
|
}
|
|
#ifndef VMCORE_VNET_OF_PROC0
|
|
if (dumptid > 0) {
|
|
tdp = (uintptr_t)TAILQ_FIRST(&proc.p_threads);
|
|
while (tdp != 0) {
|
|
if (kvm_read(kd, tdp, &td, sizeof(td)) !=
|
|
sizeof(td)) {
|
|
_kvm_err(kd, kd->program, "%s: thread",
|
|
__func__);
|
|
return (-1);
|
|
}
|
|
if (td.td_tid == dumptid) {
|
|
credp = (uintptr_t)td.td_ucred;
|
|
break;
|
|
}
|
|
tdp = (uintptr_t)TAILQ_NEXT(&td, td_plist);
|
|
}
|
|
} else
|
|
#endif
|
|
if (proc.p_pid == pid)
|
|
credp = (uintptr_t)proc.p_ucred;
|
|
if (credp != 0)
|
|
break;
|
|
procp = (uintptr_t)LIST_NEXT(&proc, p_list);
|
|
}
|
|
if (credp == 0) {
|
|
_kvm_err(kd, kd->program, "%s: pid/tid not found", __func__);
|
|
return (-1);
|
|
}
|
|
if (kvm_read(kd, (uintptr_t)credp, &cred, sizeof(cred)) !=
|
|
sizeof(cred)) {
|
|
_kvm_err(kd, kd->program, "%s: cred", __func__);
|
|
return (-1);
|
|
}
|
|
if (cred.cr_prison == NULL) {
|
|
_kvm_err(kd, kd->program, "%s: no jail", __func__);
|
|
return (-1);
|
|
}
|
|
if (kvm_read(kd, (uintptr_t)cred.cr_prison, &prison, sizeof(prison)) !=
|
|
sizeof(prison)) {
|
|
_kvm_err(kd, kd->program, "%s: prison", __func__);
|
|
return (-1);
|
|
}
|
|
if (prison.pr_vnet == NULL) {
|
|
_kvm_err(kd, kd->program, "%s: no vnet", __func__);
|
|
return (-1);
|
|
}
|
|
if (kvm_read(kd, (uintptr_t)prison.pr_vnet, &vnet, sizeof(vnet)) !=
|
|
sizeof(vnet)) {
|
|
_kvm_err(kd, kd->program, "%s: vnet", __func__);
|
|
return (-1);
|
|
}
|
|
if (vnet.vnet_magic_n != VNET_MAGIC_N) {
|
|
_kvm_err(kd, kd->program, "%s: invalid vnet magic#", __func__);
|
|
return (-1);
|
|
}
|
|
kd->vnet_initialized = 1;
|
|
kd->vnet_start = nl[NLIST_START_VNET].n_value;
|
|
kd->vnet_stop = nl[NLIST_STOP_VNET].n_value;
|
|
kd->vnet_current = (uintptr_t)prison.pr_vnet;
|
|
kd->vnet_base = vnet.vnet_data_base;
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Check whether the vnet module has been initialized sucessfully
|
|
* or not, intialize it if permitted.
|
|
*/
|
|
int
|
|
_kvm_vnet_initialized(kvm_t *kd, int intialize)
|
|
{
|
|
|
|
if (kd->vnet_initialized || !intialize)
|
|
return (kd->vnet_initialized);
|
|
|
|
(void) _kvm_vnet_selectpid(kd, getpid());
|
|
|
|
return (kd->vnet_initialized);
|
|
}
|
|
|
|
/*
|
|
* Check whether the value is within the vnet symbol range and
|
|
* only if so adjust the offset relative to the current base.
|
|
*/
|
|
uintptr_t
|
|
_kvm_vnet_validaddr(kvm_t *kd, uintptr_t value)
|
|
{
|
|
|
|
if (value == 0)
|
|
return (value);
|
|
|
|
if (!kd->vnet_initialized)
|
|
return (value);
|
|
|
|
if (value < kd->vnet_start || value >= kd->vnet_stop)
|
|
return (value);
|
|
|
|
return (kd->vnet_base + value);
|
|
}
|