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/* $OpenBSD: linux_exec.c,v 1.7 1998/03/06 22:14:01 niklas Exp $ */
/* $NetBSD: linux_exec.c,v 1.13 1996/04/05 00:01:10 christos Exp $ */
/*
* Copyright (c) 1995 Frank van der Linden
* Copyright (c) 1994 Christos Zoulas
* 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.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 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.
*
* based on exec_aout.c, sunos_exec.c and svr4_exec.c
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/kernel.h>
#include <sys/proc.h>
#include <sys/malloc.h>
#include <sys/namei.h>
#include <sys/vnode.h>
#include <sys/mount.h>
#include <sys/exec_elf.h>
#include <sys/exec_olf.h>
#include <sys/mman.h>
#include <sys/syscallargs.h>
#include <vm/vm.h>
#include <vm/vm_param.h>
#include <vm/vm_map.h>
#include <machine/cpu.h>
#include <machine/reg.h>
#include <machine/exec.h>
#include <machine/linux_machdep.h>
#include <compat/linux/linux_types.h>
#include <compat/linux/linux_syscall.h>
#include <compat/linux/linux_signal.h>
#include <compat/linux/linux_syscallargs.h>
#include <compat/linux/linux_util.h>
#include <compat/linux/linux_exec.h>
static void *linux_aout_copyargs __P((struct exec_package *,
struct ps_strings *, void *, void *));
#define LINUX_AOUT_AUX_ARGSIZ 2
#define LINUX_ELF_AUX_ARGSIZ (sizeof(AuxInfo) * 8 / sizeof(char *))
const char linux_emul_path[] = "/emul/linux";
extern int linux_error[];
extern char linux_sigcode[], linux_esigcode[];
extern struct sysent linux_sysent[];
extern char *linux_syscallnames[];
int exec_linux_aout_prep_zmagic __P((struct proc *, struct exec_package *));
int exec_linux_aout_prep_nmagic __P((struct proc *, struct exec_package *));
int exec_linux_aout_prep_omagic __P((struct proc *, struct exec_package *));
int exec_linux_aout_prep_qmagic __P((struct proc *, struct exec_package *));
struct emul emul_linux_aout = {
"linux",
linux_error,
linux_sendsig,
LINUX_SYS_syscall,
LINUX_SYS_MAXSYSCALL,
linux_sysent,
linux_syscallnames,
LINUX_AOUT_AUX_ARGSIZ,
linux_aout_copyargs,
setregs,
NULL,
linux_sigcode,
linux_esigcode,
};
struct emul emul_linux_elf = {
"linux",
linux_error,
linux_sendsig,
LINUX_SYS_syscall,
LINUX_SYS_MAXSYSCALL,
linux_sysent,
linux_syscallnames,
LINUX_ELF_AUX_ARGSIZ,
elf_copyargs,
setregs,
exec_elf_fixup,
linux_sigcode,
linux_esigcode,
};
static void *
linux_aout_copyargs(pack, arginfo, stack, argp)
struct exec_package *pack;
struct ps_strings *arginfo;
void *stack;
void *argp;
{
char **cpp = stack;
char **stk = stack;
char *dp, *sp;
size_t len;
void *nullp = NULL;
int argc = arginfo->ps_nargvstr;
int envc = arginfo->ps_nenvstr;
if (copyout(&argc, cpp++, sizeof(argc)))
return (NULL);
/* leave room for envp and argv */
cpp += 2;
if (copyout(&cpp, &stk[1], sizeof (cpp)))
return (NULL);
dp = (char *)(cpp + argc + envc + 2);
sp = argp;
/* XXX don't copy them out, remap them! */
arginfo->ps_argvstr = cpp; /* remember location of argv for later */
for (; --argc >= 0; sp += len, dp += len)
if (copyout(&dp, cpp++, sizeof(dp)) ||
copyoutstr(sp, dp, ARG_MAX, &len))
return (NULL);
if (copyout(&nullp, cpp++, sizeof(nullp)))
return (NULL);
if (copyout(&cpp, &stk[2], sizeof (cpp)))
return (NULL);
arginfo->ps_envstr = cpp; /* remember location of envp for later */
for (; --envc >= 0; sp += len, dp += len)
if (copyout(&dp, cpp++, sizeof(dp)) ||
copyoutstr(sp, dp, ARG_MAX, &len))
return (NULL);
if (copyout(&nullp, cpp++, sizeof(nullp)))
return (NULL);
return (cpp);
}
int
exec_linux_aout_makecmds(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *linux_ep = epp->ep_hdr;
int machtype, magic;
int error = ENOEXEC;
magic = LINUX_N_MAGIC(linux_ep);
machtype = LINUX_N_MACHTYPE(linux_ep);
if (machtype != LINUX_MID_MACHINE)
return (ENOEXEC);
switch (magic) {
case QMAGIC:
error = exec_linux_aout_prep_qmagic(p, epp);
break;
case ZMAGIC:
error = exec_linux_aout_prep_zmagic(p, epp);
break;
case NMAGIC:
error = exec_linux_aout_prep_nmagic(p, epp);
break;
case OMAGIC:
error = exec_linux_aout_prep_omagic(p, epp);
break;
}
if (error == 0)
epp->ep_emul = &emul_linux_aout;
return (error);
}
/*
* Since text starts at 0x400 in Linux ZMAGIC executables, and 0x400
* is very likely not page aligned on most architectures, it is treated
* as an NMAGIC here. XXX
*/
int
exec_linux_aout_prep_zmagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
epp->ep_taddr = LINUX_N_TXTADDR(*execp, ZMAGIC);
epp->ep_tsize = execp->a_text;
epp->ep_daddr = LINUX_N_DATADDR(*execp, ZMAGIC);
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, ZMAGIC),
VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, ZMAGIC),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
epp->ep_daddr + execp->a_data, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return (exec_setup_stack(p, epp));
}
/*
* exec_aout_prep_nmagic(): Prepare Linux NMAGIC package.
* Not different from the normal stuff.
*/
int
exec_linux_aout_prep_nmagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
long bsize, baddr;
epp->ep_taddr = LINUX_N_TXTADDR(*execp, NMAGIC);
epp->ep_tsize = execp->a_text;
epp->ep_daddr = LINUX_N_DATADDR(*execp, NMAGIC);
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, NMAGIC),
VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, NMAGIC),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0)
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return (exec_setup_stack(p, epp));
}
/*
* exec_aout_prep_omagic(): Prepare Linux OMAGIC package.
* Business as usual.
*/
int
exec_linux_aout_prep_omagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
long dsize, bsize, baddr;
epp->ep_taddr = LINUX_N_TXTADDR(*execp, OMAGIC);
epp->ep_tsize = execp->a_text;
epp->ep_daddr = LINUX_N_DATADDR(*execp, OMAGIC);
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/* set up command for text and data segments */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn,
execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp,
LINUX_N_TXTOFF(*execp, OMAGIC), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
baddr = roundup(epp->ep_daddr + execp->a_data, NBPG);
bsize = epp->ep_daddr + epp->ep_dsize - baddr;
if (bsize > 0)
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/*
* Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize);
* obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are
* computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize'
* respectively to page boundaries.
* Compensate `ep_dsize' for the amount of data covered by the last
* text page.
*/
dsize = epp->ep_dsize + execp->a_text - roundup(execp->a_text, NBPG);
epp->ep_dsize = (dsize > 0) ? dsize : 0;
return (exec_setup_stack(p, epp));
}
int
exec_linux_aout_prep_qmagic(p, epp)
struct proc *p;
struct exec_package *epp;
{
struct exec *execp = epp->ep_hdr;
epp->ep_taddr = LINUX_N_TXTADDR(*execp, QMAGIC);
epp->ep_tsize = execp->a_text;
epp->ep_daddr = LINUX_N_DATADDR(*execp, QMAGIC);
epp->ep_dsize = execp->a_data + execp->a_bss;
epp->ep_entry = execp->a_entry;
/*
* check if vnode is in open for writing, because we want to
* demand-page out of it. if it is, don't do it, for various
* reasons
*/
if ((execp->a_text != 0 || execp->a_data != 0) &&
epp->ep_vp->v_writecount != 0) {
#ifdef DIAGNOSTIC
if (epp->ep_vp->v_flag & VTEXT)
panic("exec: a VTEXT vnode has writecount != 0\n");
#endif
return (ETXTBSY);
}
epp->ep_vp->v_flag |= VTEXT;
/* set up command for text segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_text,
epp->ep_taddr, epp->ep_vp, LINUX_N_TXTOFF(*execp, QMAGIC),
VM_PROT_READ|VM_PROT_EXECUTE);
/* set up command for data segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, execp->a_data,
epp->ep_daddr, epp->ep_vp, LINUX_N_DATOFF(*execp, QMAGIC),
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
/* set up command for bss segment */
NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss,
epp->ep_daddr + execp->a_data, NULLVP, 0,
VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
return (exec_setup_stack(p, epp));
}
int
linux_elf_probe(p, epp, itp, pos, os)
struct proc *p;
struct exec_package *epp;
char *itp;
u_long *pos;
u_int8_t *os;
{
char *bp;
int error;
size_t len;
if (itp[0]) {
if ((error = emul_find(p, NULL, linux_emul_path, itp, &bp, 0)))
return (error);
if ((error = copystr(bp, itp, MAXPATHLEN, &len)))
return (error);
free(bp, M_TEMP);
}
epp->ep_emul = &emul_linux_elf;
*pos = ELF32_NO_ADDR;
if (*os == OOS_NULL)
*os = OOS_LINUX;
return (0);
}
/*
* The Linux system call to load shared libraries, a.out version. The
* a.out shared libs are just files that are mapped onto a fixed
* address in the process' address space. The address is given in
* a_entry. Read in the header, set up some VM commands and run them.
*
* Yes, both text and data are mapped at once, so we're left with
* writeable text for the shared libs. The Linux crt0 seemed to break
* sometimes when data was mapped seperately. It munmapped a uselib()
* of ld.so by hand, which failed with shared text and data for ld.so
* Yuck.
*
* Because of the problem with ZMAGIC executables (text starts
* at 0x400 in the file, but needs to be mapped at 0), ZMAGIC
* shared libs are not handled very efficiently :-(
*/
int
linux_sys_uselib(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct linux_sys_uselib_args /* {
syscallarg(char *) path;
} */ *uap = v;
caddr_t sg;
long bsize, dsize, tsize, taddr, baddr, daddr;
struct nameidata ni;
struct vnode *vp;
struct exec hdr;
struct exec_vmcmd_set vcset;
int rem, i, magic, error;
sg = stackgap_init(p->p_emul);
LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
NDINIT(&ni, LOOKUP, FOLLOW, UIO_USERSPACE, SCARG(uap, path), p);
if ((error = namei(&ni)))
return (error);
vp = ni.ni_vp;
if ((error = vn_rdwr(UIO_READ, vp, (caddr_t) &hdr, LINUX_AOUT_HDR_SIZE,
0, UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred,
&rem, p))) {
vrele(vp);
return (error);
}
if (rem != 0) {
vrele(vp);
return (ENOEXEC);
}
if (LINUX_N_MACHTYPE(&hdr) != LINUX_MID_MACHINE)
return (ENOEXEC);
magic = LINUX_N_MAGIC(&hdr);
taddr = hdr.a_entry & (~(NBPG - 1));
tsize = hdr.a_text;
daddr = taddr + tsize;
dsize = hdr.a_data + hdr.a_bss;
if ((hdr.a_text != 0 || hdr.a_data != 0) && vp->v_writecount != 0) {
vrele(vp);
return (ETXTBSY);
}
vp->v_flag |= VTEXT;
vcset.evs_cnt = 0;
vcset.evs_used = 0;
NEW_VMCMD(
&vcset, magic == ZMAGIC ? vmcmd_map_readvn : vmcmd_map_pagedvn,
hdr.a_text + hdr.a_data, taddr, vp, LINUX_N_TXTOFF(hdr, magic),
VM_PROT_READ|VM_PROT_EXECUTE|VM_PROT_WRITE);
baddr = roundup(daddr + hdr.a_data, NBPG);
bsize = daddr + dsize - baddr;
if (bsize > 0) {
NEW_VMCMD(&vcset, vmcmd_map_zero, bsize, baddr,
NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE);
}
for (i = 0; i < vcset.evs_used && !error; i++) {
struct exec_vmcmd *vcp;
vcp = &vcset.evs_cmds[i];
error = (*vcp->ev_proc)(p, vcp);
}
kill_vmcmds(&vcset);
vrele(vp);
return (error);
}
/*
* Execve(2). Just check the alternate emulation path, and pass it on
* to the regular execve().
*/
int
linux_sys_execve(p, v, retval)
struct proc *p;
void *v;
register_t *retval;
{
struct linux_sys_execve_args /* {
syscallarg(char *) path;
syscallarg(char **) argv;
syscallarg(char **) envp;
} */ *uap = v;
struct sys_execve_args ap;
caddr_t sg;
sg = stackgap_init(p->p_emul);
LINUX_CHECK_ALT_EXIST(p, &sg, SCARG(uap, path));
SCARG(&ap, path) = SCARG(uap, path);
SCARG(&ap, argp) = SCARG(uap, argp);
SCARG(&ap, envp) = SCARG(uap, envp);
return (sys_execve(p, &ap, retval));
}
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