sys/emulation/linux/i386/imgact_linux.c

   1 /*-
   2  * Copyright (c) 1994-1996 Søren Schmidt
   3  * All rights reserved.
   4  *
   5  * Based heavily on /sys/kern/imgact_aout.c which is:
   6  * Copyright (c) 1993, David Greenman
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer
  13  *    in this position and unchanged.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. The name of the author may not be used to endorse or promote products
  18  *    derived from this software without specific prior written permission
  19  *
  20  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  21  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  22  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  23  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  24  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  25  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  29  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  *
  31  * $FreeBSD: src/sys/i386/linux/imgact_linux.c,v 1.35.2.2 2001/11/03 01:41:08 ps Exp $
  32  * $DragonFly: src/sys/emulation/linux/i386/imgact_linux.c,v 1.10 2006/12/28 21:24:02 dillon Exp $
  33  */
  34
  35 #include <sys/param.h>
  36 #include <sys/systm.h>
  37 #include <sys/resourcevar.h>
  38 #include <sys/exec.h>
  39 #include <sys/mman.h>
  40 #include <sys/imgact.h>
  41 #include <sys/imgact_aout.h>
  42 #include <sys/kernel.h>
  43 #include <sys/lock.h>
  44 #include <sys/proc.h>
  45 #include <sys/vnode.h>
  46
  47 #include <vm/vm.h>
  48 #include <vm/vm_kern.h>
  49 #include <vm/vm_param.h>
  50 #include <vm/pmap.h>
  51 #include <vm/vm_map.h>
  52 #include <vm/vm_extern.h>
  53
  54 #include "linux.h"
  55
  56 static int      exec_linux_imgact (struct image_params *iparams);
  57
  58 static int
  59 exec_linux_imgact(struct image_params *imgp)
  60 {
  61     const struct exec *a_out = (const struct exec *) imgp->image_header;
  62     struct vmspace *vmspace;
  63     vm_offset_t vmaddr;
  64     unsigned long virtual_offset, file_offset;
  65     vm_offset_t buffer;
  66     unsigned long bss_size;
  67     int error;
  68
  69     if (((a_out->a_magic >> 16) & 0xff) != 0x64)
  70         return -1;
  71
  72     /*
  73      * Set file/virtual offset based on a.out variant.
  74      */
  75     switch ((int)(a_out->a_magic & 0xffff)) {
  76     case 0413:
  77         virtual_offset = 0;
  78         file_offset = 1024;
  79         break;
  80     case 0314:
  81         virtual_offset = 4096;
  82         file_offset = 0;
  83         break;
  84     default:
  85         return (-1);
  86     }
  87     bss_size = round_page(a_out->a_bss);
  88 #ifdef DEBUG
  89     kprintf("imgact: text: %08lx, data: %08lx, bss: %08lx\n",
  90         (u_long)a_out->a_text, (u_long)a_out->a_data, bss_size);
  91 #endif
  92
  93     /*
  94      * Check various fields in header for validity/bounds.
  95      */
  96     if (a_out->a_entry < virtual_offset ||
  97         a_out->a_entry >= virtual_offset + a_out->a_text ||
  98         a_out->a_text & PAGE_MASK || a_out->a_data & PAGE_MASK)
  99         return (-1);
 100
 101     /* text + data can't exceed file size */
 102     if (a_out->a_data + a_out->a_text > imgp->attr->va_size)
 103         return (EFAULT);
 104     /*
 105      * text/data/bss must not exceed limits
 106      */
 107     if (a_out->a_text > maxtsiz ||
 108         a_out->a_data + bss_size > imgp->proc->p_rlimit[RLIMIT_DATA].rlim_cur)
 109         return (ENOMEM);
 110
 111     /*
 112      * Destroy old process VM and create a new one (with a new stack)
 113      */
 114     exec_new_vmspace(imgp, NULL);
 115     vmspace = imgp->proc->p_vmspace;
 116
 117     /*
 118      * Check if file_offset page aligned,.
 119      * Currently we cannot handle misalinged file offsets,
 120      * and so we read in the entire image (what a waste).
 121      */
 122     if (file_offset & PAGE_MASK) {
 123 #ifdef DEBUG
 124         kprintf("imgact: Non page aligned binary %lu\n", file_offset);
 125 #endif
 126         /*
 127          * Map text+data+bss read/write/execute
 128          */
 129         vmaddr = virtual_offset;
 130         error = vm_map_find(&vmspace->vm_map, NULL, NULL,
 131                             0, &vmaddr,
 132                             a_out->a_text + a_out->a_data + bss_size,
 133                             PAGE_SIZE,
 134                             FALSE, VM_MAPTYPE_NORMAL,
 135                             VM_PROT_ALL, VM_PROT_ALL, 0);
 136         if (error)
 137             return error;
 138
 139         error = vm_mmap(&kernel_map, &buffer,
 140                         round_page(a_out->a_text + a_out->a_data + file_offset),
 141                         VM_PROT_READ, VM_PROT_READ, 0,
 142                         (caddr_t) imgp->vp, trunc_page(file_offset));
 143         if (error)
 144             return error;
 145
 146         error = copyout((caddr_t)(void *)(uintptr_t)(buffer + file_offset),
 147                         (caddr_t)vmaddr, a_out->a_text + a_out->a_data);
 148
 149         vm_map_remove(&kernel_map, buffer,
 150                       buffer + round_page(a_out->a_text + a_out->a_data + file_offset));
 151
 152         if (error)
 153             return error;
 154
 155         /*
 156          * remove write enable on the 'text' part
 157          */
 158         error = vm_map_protect(&vmspace->vm_map,
 159                                vmaddr,
 160                                vmaddr + a_out->a_text,
 161                                VM_PROT_EXECUTE|VM_PROT_READ,
 162                                TRUE);
 163         if (error)
 164             return error;
 165     }
 166     else {
 167 #ifdef DEBUG
 168         kprintf("imgact: Page aligned binary %lu\n", file_offset);
 169 #endif
 170         /*
 171          * Map text+data read/execute
 172          */
 173         vmaddr = virtual_offset;
 174         error = vm_mmap(&vmspace->vm_map, &vmaddr,
 175                         a_out->a_text + a_out->a_data,
 176                         VM_PROT_READ | VM_PROT_EXECUTE,
 177                         VM_PROT_ALL,
 178                         MAP_PRIVATE | MAP_FIXED,
 179                         (caddr_t)imgp->vp, file_offset);
 180         if (error)
 181             return (error);
 182
 183 #ifdef DEBUG
 184         kprintf("imgact: startaddr=%08lx, length=%08lx\n",
 185             (u_long)vmaddr, a_out->a_text + a_out->a_data);
 186 #endif
 187         /*
 188          * allow read/write of data
 189          */
 190         error = vm_map_protect(&vmspace->vm_map,
 191                                vmaddr + a_out->a_text,
 192                                vmaddr + a_out->a_text + a_out->a_data,
 193                                VM_PROT_ALL,
 194                                FALSE);
 195         if (error)
 196             return (error);
 197
 198         /*
 199          * Allocate anon demand-zeroed area for uninitialized data
 200          */
 201         if (bss_size != 0) {
 202             vmaddr = virtual_offset + a_out->a_text + a_out->a_data;
 203             error = vm_map_find(&vmspace->vm_map, NULL, NULL,
 204                                 0, &vmaddr,
 205                                 bss_size, PAGE_SIZE,
 206                                 FALSE, VM_MAPTYPE_NORMAL,
 207                                 VM_PROT_ALL, VM_PROT_ALL,
 208                                 0);
 209             if (error)
 210                 return (error);
 211 #ifdef DEBUG
 212             kprintf("imgact: bssaddr=%08lx, length=%08lx\n",
 213                 (u_long)vmaddr, bss_size);
 214 #endif
 215
 216         }
 217         /* Indicate that this file should not be modified */
 218         imgp->vp->v_flag |= VTEXT;
 219     }
 220     /* Fill in process VM information */
 221     vmspace->vm_tsize = round_page(a_out->a_text) >> PAGE_SHIFT;
 222     vmspace->vm_dsize = round_page(a_out->a_data + bss_size) >> PAGE_SHIFT;
 223     vmspace->vm_taddr = (caddr_t)(void *)(uintptr_t)virtual_offset;
 224     vmspace->vm_daddr = (caddr_t)(void *)(uintptr_t)
 225         (virtual_offset + a_out->a_text);
 226
 227     /* Fill in image_params */
 228     imgp->interpreted = 0;
 229     imgp->entry_addr = a_out->a_entry;
 230
 231     imgp->proc->p_sysent = &linux_sysvec;
 232     return (0);
 233 }
 234
 235 /*
 236  * Tell kern_execve.c about it, with a little help from the linker.
 237  */
 238 static struct execsw linux_execsw = { exec_linux_imgact, "linux a.out" };
 239 EXEC_SET(linuxaout, linux_execsw);