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