freebsd-skq/sys/i386/linux/imgact_linux.c
dillon ce08285d5a Fix #! script exec under linux emulation. If a script is exec'd from a
program running under linux emulation, the script binary is checked for
    in /compat/linux first.  Without this patch the wrong script binary
    (i.e. the FreeBSD binary) will be run instead of the linux binary.
    For example, #!/bin/sh, thus breaking out of linux compatibility mode.

    This solves a number of problems people have had installing linux
    software on FreeBSD boxes.
2000-04-26 20:58:40 +00:00

238 lines
6.9 KiB
C

/*-
* Copyright (c) 1994-1996 Søren Schmidt
* All rights reserved.
*
* Based heavily on /sys/kern/imgact_aout.c which is:
* Copyright (c) 1993, David Greenman
*
* 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
* in this position and unchanged.
* 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 withough 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.
*
* $FreeBSD$
*/
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/resourcevar.h>
#include <sys/exec.h>
#include <sys/mman.h>
#include <sys/imgact.h>
#include <sys/imgact_aout.h>
#include <sys/kernel.h>
#include <sys/lock.h>
#include <sys/proc.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/vm_kern.h>
#include <vm/vm_param.h>
#include <vm/pmap.h>
#include <vm/vm_map.h>
#include <vm/vm_extern.h>
#include <i386/linux/linux.h>
static int exec_linux_imgact __P((struct image_params *iparams));
static int
exec_linux_imgact(imgp)
struct image_params *imgp;
{
const struct exec *a_out = (const struct exec *) imgp->image_header;
struct vmspace *vmspace;
vm_offset_t vmaddr;
unsigned long virtual_offset, file_offset;
vm_offset_t buffer;
unsigned long bss_size;
int error;
if (((a_out->a_magic >> 16) & 0xff) != 0x64)
return -1;
/*
* Set file/virtual offset based on a.out variant.
*/
switch ((int)(a_out->a_magic & 0xffff)) {
case 0413:
virtual_offset = 0;
file_offset = 1024;
break;
case 0314:
virtual_offset = 4096;
file_offset = 0;
break;
default:
return (-1);
}
bss_size = round_page(a_out->a_bss);
#ifdef DEBUG
printf("imgact: text: %08lx, data: %08lx, bss: %08lx\n",
(u_long)a_out->a_text, (u_long)a_out->a_data, bss_size);
#endif
/*
* Check various fields in header for validity/bounds.
*/
if (a_out->a_entry < virtual_offset ||
a_out->a_entry >= virtual_offset + a_out->a_text ||
a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK)
return (-1);
/* text + data can't exceed file size */
if (a_out->a_data + a_out->a_text > imgp->attr->va_size)
return (EFAULT);
/*
* text/data/bss must not exceed limits
*/
if (a_out->a_text > MAXTSIZ ||
a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur)
return (ENOMEM);
/* copy in arguments and/or environment from old process */
error = exec_extract_strings(imgp);
if (error)
return (error);
/*
* Destroy old process VM and create a new one (with a new stack)
*/
exec_new_vmspace(imgp);
vmspace = imgp->proc->p_vmspace;
/*
* Check if file_offset page aligned,.
* Currently we cannot handle misalinged file offsets,
* and so we read in the entire image (what a waste).
*/
if (file_offset & PAGE_MASK) {
#ifdef DEBUG
printf("imgact: Non page aligned binary %lu\n", file_offset);
#endif
/*
* Map text+data+bss read/write/execute
*/
vmaddr = virtual_offset;
error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
a_out->a_text + a_out->a_data + bss_size, FALSE,
VM_PROT_ALL, VM_PROT_ALL, 0);
if (error)
return error;
error = vm_mmap(kernel_map, &buffer,
round_page(a_out->a_text + a_out->a_data + file_offset),
VM_PROT_READ, VM_PROT_READ, 0,
(caddr_t) imgp->vp, trunc_page(file_offset));
if (error)
return error;
error = copyout((caddr_t)(void *)(uintptr_t)(buffer + file_offset),
(caddr_t)vmaddr, a_out->a_text + a_out->a_data);
vm_map_remove(kernel_map, buffer,
buffer + round_page(a_out->a_text + a_out->a_data + file_offset));
if (error)
return error;
/*
* remove write enable on the 'text' part
*/
error = vm_map_protect(&vmspace->vm_map,
vmaddr,
vmaddr + a_out->a_text,
VM_PROT_EXECUTE|VM_PROT_READ,
TRUE);
if (error)
return error;
}
else {
#ifdef DEBUG
printf("imgact: Page aligned binary %lu\n", file_offset);
#endif
/*
* Map text+data read/execute
*/
vmaddr = virtual_offset;
error = vm_mmap(&vmspace->vm_map, &vmaddr,
a_out->a_text + a_out->a_data,
VM_PROT_READ | VM_PROT_EXECUTE,
VM_PROT_ALL,
MAP_PRIVATE | MAP_FIXED,
(caddr_t)imgp->vp, file_offset);
if (error)
return (error);
#ifdef DEBUG
printf("imgact: startaddr=%08lx, length=%08lx\n",
(u_long)vmaddr, a_out->a_text + a_out->a_data);
#endif
/*
* allow read/write of data
*/
error = vm_map_protect(&vmspace->vm_map,
vmaddr + a_out->a_text,
vmaddr + a_out->a_text + a_out->a_data,
VM_PROT_ALL,
FALSE);
if (error)
return (error);
/*
* Allocate anon demand-zeroed area for uninitialized data
*/
if (bss_size != 0) {
vmaddr = virtual_offset + a_out->a_text + a_out->a_data;
error = vm_map_find(&vmspace->vm_map, NULL, 0, &vmaddr,
bss_size, FALSE, VM_PROT_ALL, VM_PROT_ALL, 0);
if (error)
return (error);
#ifdef DEBUG
printf("imgact: bssaddr=%08lx, length=%08lx\n",
(u_long)vmaddr, bss_size);
#endif
}
/* Indicate that this file should not be modified */
imgp->vp->v_flag |= VTEXT;
}
/* Fill in process VM information */
vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT;
vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT;
vmspace->vm_taddr = (caddr_t)(void *)(uintptr_t)virtual_offset;
vmspace->vm_daddr = (caddr_t)(void *)(uintptr_t)
(virtual_offset + a_out->a_text);
/* Fill in image_params */
imgp->interpreted = 0;
imgp->entry_addr = a_out->a_entry;
imgp->proc->p_sysent = &linux_sysvec;
return (0);
}
/*
* Tell kern_execve.c about it, with a little help from the linker.
*/
static struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" };
EXEC_SET(linuxaout, linux_execsw);