NetBSD-5.0.2/sys/compat/linux/arch/i386/linux_ptrace.c
/* $NetBSD: linux_ptrace.c,v 1.22 2008/04/28 20:23:42 martin Exp $ */
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Matthias Scheler.
*
* 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: linux_ptrace.c,v 1.22 2008/04/28 20:23:42 martin Exp $");
#include <sys/param.h>
#include <sys/malloc.h>
#include <sys/mount.h>
#include <sys/proc.h>
#include <sys/ptrace.h>
#include <sys/systm.h>
#include <sys/syscall.h>
#include <sys/syscallargs.h>
#include <uvm/uvm_extern.h>
#include <machine/reg.h>
#include <compat/linux/common/linux_types.h>
#include <compat/linux/common/linux_ptrace.h>
#include <compat/linux/common/linux_signal.h>
#include <compat/linux/common/linux_util.h>
#include <compat/linux/common/linux_machdep.h>
#include <compat/linux/common/linux_emuldata.h>
#include <compat/linux/common/linux_exec.h> /* for emul_linux */
#include <compat/linux/linux_syscallargs.h>
#include <lib/libkern/libkern.h> /* for offsetof() */
struct linux_reg {
long ebx;
long ecx;
long edx;
long esi;
long edi;
long ebp;
long eax;
long xds, xes; /* unsigned short ds, __ds, es, __es; */
long __fs, __gs; /* unsigned short fs, __fs, gs, __gs; */
long orig_eax;
long eip;
long xcs; /* unsigned short cs, __cs; */
long eflags;
long esp;
long xss; /* unsigned short ss, __ss; */
};
/* structure used for storing floating point context */
struct linux_fpctx {
long cwd;
long swd;
long twd;
long fip;
long fcs;
long foo;
long fos;
long st_space[20];
};
/* user struct for linux process - this is used for Linux ptrace emulation */
/* most of it is junk only used by gdb */
struct linux_user {
struct linux_reg regs; /* registers */
int u_fpvalid; /* true if math co-processor being used. */
struct linux_fpctx i387; /* Math Co-processor registers. */
/* The rest of this junk is to help gdb figure out what goes where */
#define lusr_startgdb u_tsize
unsigned long int u_tsize; /* Text segment size (pages). */
unsigned long int u_dsize; /* Data segment size (pages). */
unsigned long int u_ssize; /* Stack segment size (pages). */
unsigned long start_code; /* Starting virtual address of text. */
unsigned long start_stack; /* Starting virtual address of stack
area. This is actually the bottom of
the stack, the top of the stack is
always found in the esp register. */
long int __signal; /* Signal that caused the core dump. */
int __reserved; /* unused */
void *u_ar0; /* Used by gdb to help find the values
for the registers. */
struct linux_fpctx *u_fpstate; /* Math Co-processor pointer. */
unsigned long __magic; /* To uniquely identify a core file */
char u_comm[32]; /* User command that was responsible */
int u_debugreg[8];
#define u_debugreg_end u_debugreg[7]
};
#define LUSR_OFF(member) offsetof(struct linux_user, member)
#define ISSET(t, f) ((t) & (f))
int linux_ptrace_disabled = 1; /* bitrotted */
int
linux_sys_ptrace_arch(struct lwp *l, const struct linux_sys_ptrace_args *uap, register_t *retval)
{
/* {
syscallarg(int) request;
syscallarg(int) pid;
syscallarg(int) addr;
syscallarg(int) data;
} */
struct proc *p = l->l_proc;
int request, error;
struct proc *t; /* target process */
struct lwp *lt;
struct reg *regs = NULL;
struct fpreg *fpregs = NULL;
struct linux_reg *linux_regs = NULL;
struct linux_fpctx *linux_fpregs = NULL;
int addr;
if (linux_ptrace_disabled)
return ENOSYS;
request = SCARG(uap, request);
if ((request != LINUX_PTRACE_PEEKUSR) &&
(request != LINUX_PTRACE_POKEUSR) &&
(request != LINUX_PTRACE_GETREGS) &&
(request != LINUX_PTRACE_SETREGS) &&
(request != LINUX_PTRACE_GETFPREGS) &&
(request != LINUX_PTRACE_SETFPREGS))
return EIO;
/* XXXAD locking */
/* Find the process we're supposed to be operating on. */
if ((t = pfind(SCARG(uap, pid))) == NULL)
return ESRCH;
/*
* You can't do what you want to the process if:
* (1) It's not being traced at all,
*/
if (!ISSET(t->p_slflag, PSL_TRACED))
return EPERM;
/*
* (2) it's being traced by procfs (which has
* different signal delivery semantics),
*/
if (ISSET(t->p_slflag, PSL_FSTRACE))
return EBUSY;
/*
* (3) it's not being traced by _you_, or
*/
if (t->p_pptr != p)
return EBUSY;
/*
* (4) it's not currently stopped.
*/
if (t->p_stat != SSTOP || !t->p_waited /* XXXSMP */)
return EBUSY;
/* XXX NJWLWP
* The entire ptrace interface needs work to be useful to
* a process with multiple LWPs. For the moment, we'll
* just kluge this and fail on others.
*/
if (p->p_nlwps > 1)
return (ENOSYS);
lt = LIST_FIRST(&t->p_lwps);
*retval = 0;
switch (request) {
case LINUX_PTRACE_GETREGS:
MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
MALLOC(linux_regs, struct linux_reg*, sizeof(struct linux_reg),
M_TEMP, M_WAITOK);
error = process_read_regs(lt, regs);
if (error != 0)
goto out;
linux_regs->ebx = regs->r_ebx;
linux_regs->ecx = regs->r_ecx;
linux_regs->edx = regs->r_edx;
linux_regs->esi = regs->r_esi;
linux_regs->edi = regs->r_edi;
linux_regs->ebp = regs->r_ebp;
linux_regs->eax = regs->r_eax;
linux_regs->xds = regs->r_ds;
linux_regs->xes = regs->r_es;
linux_regs->orig_eax = regs->r_eax; /* XXX is this correct? */
linux_regs->eip = regs->r_cs + regs->r_eip;
linux_regs->xcs = regs->r_cs;
linux_regs->eflags = regs->r_eflags;
linux_regs->esp = regs->r_esp;
linux_regs->xss = regs->r_ss;
error = copyout(linux_regs, (void *)SCARG(uap, data),
sizeof(struct linux_reg));
goto out;
case LINUX_PTRACE_SETREGS:
MALLOC(regs, struct reg*, sizeof(struct reg), M_TEMP, M_WAITOK);
MALLOC(linux_regs, struct linux_reg *, sizeof(struct linux_reg),
M_TEMP, M_WAITOK);
error = copyin((void *)SCARG(uap, data), linux_regs,
sizeof(struct linux_reg));
if (error != 0)
goto out;
regs->r_ebx = linux_regs->ebx;
regs->r_ecx = linux_regs->ecx;
regs->r_edx = linux_regs->edx;
regs->r_esi = linux_regs->esi;
regs->r_edi = linux_regs->edi;
regs->r_ebp = linux_regs->ebp;
regs->r_eax = linux_regs->eax;
regs->r_ds = linux_regs->xds;
regs->r_es = linux_regs->xes;
regs->r_eip = linux_regs->eip - linux_regs->xcs;
regs->r_cs = linux_regs->xcs;
regs->r_eflags = linux_regs->eflags;
regs->r_esp = linux_regs->esp;
regs->r_ss = linux_regs->xss;
error = process_write_regs(lt, regs);
goto out;
case LINUX_PTRACE_GETFPREGS:
MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg),
M_TEMP, M_WAITOK);
MALLOC(linux_fpregs, struct linux_fpctx *,
sizeof(struct linux_fpctx), M_TEMP, M_WAITOK);
error = process_read_fpregs(lt, fpregs);
if (error != 0)
goto out;
/* zero the contents if NetBSD fpreg structure is smaller */
if (sizeof(struct fpreg) < sizeof(struct linux_fpctx))
memset(linux_fpregs, '\0', sizeof(struct linux_fpctx));
memcpy(linux_fpregs, fpregs,
min(sizeof(struct linux_fpctx), sizeof(struct fpreg)));
error = copyout(linux_fpregs, (void *)SCARG(uap, data),
sizeof(struct linux_fpctx));
goto out;
case LINUX_PTRACE_SETFPREGS:
MALLOC(fpregs, struct fpreg *, sizeof(struct fpreg),
M_TEMP, M_WAITOK);
MALLOC(linux_fpregs, struct linux_fpctx *,
sizeof(struct linux_fpctx), M_TEMP, M_WAITOK);
error = copyin((void *)SCARG(uap, data), linux_fpregs,
sizeof(struct linux_fpctx));
if (error != 0)
goto out;
memset(fpregs, '\0', sizeof(struct fpreg));
memcpy(fpregs, linux_fpregs,
min(sizeof(struct linux_fpctx), sizeof(struct fpreg)));
error = process_write_regs(lt, regs);
goto out;
case LINUX_PTRACE_PEEKUSR:
addr = SCARG(uap, addr);
uvm_lwp_hold(lt); /* need full process info */
error = 0;
if (addr < LUSR_OFF(lusr_startgdb)) {
/* XXX should provide appropriate register */
error = 1;
} else if (addr == LUSR_OFF(u_tsize))
*retval = p->p_vmspace->vm_tsize;
else if (addr == LUSR_OFF(u_dsize))
*retval = p->p_vmspace->vm_dsize;
else if (addr == LUSR_OFF(u_ssize))
*retval = p->p_vmspace->vm_ssize;
else if (addr == LUSR_OFF(start_code))
*retval = (register_t) p->p_vmspace->vm_taddr;
else if (addr == LUSR_OFF(start_stack))
*retval = (register_t) p->p_vmspace->vm_minsaddr;
else if (addr == LUSR_OFF(u_ar0))
*retval = LUSR_OFF(regs);
else if (addr >= LUSR_OFF(u_debugreg)
&& addr <= LUSR_OFF(u_debugreg_end)) {
int off = (addr - LUSR_OFF(u_debugreg)) / sizeof(int);
/* only do this for Linux processes */
if (t->p_emul != &emul_linux)
error = EINVAL;
else {
*retval = ((struct linux_emuldata *)
t->p_emuldata)->debugreg[off];
}
} else if (addr == LUSR_OFF(__signal)) {
error = 1;
} else if (addr == LUSR_OFF(__signal)) {
error = 1;
} else if (addr == LUSR_OFF(u_fpstate)) {
error = 1;
} else if (addr == LUSR_OFF(__magic)) {
error = 1;
} else if (addr == LUSR_OFF(u_comm)) {
error = 1;
} else {
#ifdef DEBUG_LINUX
printf("linux_ptrace: unsupported address: %d\n", addr);
#endif
error = 1;
}
uvm_lwp_rele(lt);
if (!error)
return 0;
case LINUX_PTRACE_POKEUSR:
/* we only support setting debugregs for now */
addr = SCARG(uap, addr);
if (addr >= LUSR_OFF(u_debugreg)
&& addr <= LUSR_OFF(u_debugreg_end)) {
int off = (addr - LUSR_OFF(u_debugreg)) / sizeof(int);
int data = SCARG(uap, data);
/* only do this for Linux processes */
if (t->p_emul != &emul_linux)
return EINVAL;
uvm_lwp_hold(lt);
((struct linux_emuldata *)t->p_emuldata)->debugreg[off] = data;
uvm_lwp_rele(lt);
return (0);
}
break;
default:
/* never reached */
break;
}
return EIO;
out:
if (regs)
FREE(regs, M_TEMP);
if (fpregs)
FREE(fpregs, M_TEMP);
if (linux_regs)
FREE(linux_regs, M_TEMP);
if (linux_fpregs)
FREE(linux_fpregs, M_TEMP);
return (error);
}