1 /* $NetBSD: exec_aout.c,v 1.34 2008/11/19 18:36:06 ad Exp $ */ 2 3 /* 4 * Copyright (c) 1993, 1994 Christopher G. Demetriou 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. All advertising materials mentioning features or use of this software 16 * must display the following acknowledgement: 17 * This product includes software developed by Christopher G. Demetriou. 18 * 4. The name of the author may not be used to endorse or promote products 19 * derived from this software without specific prior written permission 20 * 21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: exec_aout.c,v 1.34 2008/11/19 18:36:06 ad Exp $"); 35 36 #ifdef _KERNEL_OPT 37 #include "opt_coredump.h" 38 #endif 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/proc.h> 43 #include <sys/malloc.h> 44 #include <sys/vnode.h> 45 #include <sys/exec.h> 46 #include <sys/exec_aout.h> 47 #include <sys/resourcevar.h> 48 #include <sys/module.h> 49 50 #include <uvm/uvm_extern.h> 51 52 #ifdef COREDUMP 53 #define DEP "coredump" 54 #else 55 #define DEP NULL 56 #endif 57 58 MODULE(MODULE_CLASS_MISC, exec_aout, DEP); 59 60 static struct execsw exec_aout_execsw[] = { 61 { sizeof(struct exec), 62 exec_aout_makecmds, 63 { NULL }, 64 &emul_netbsd, 65 EXECSW_PRIO_ANY, 66 0, 67 copyargs, 68 NULL, 69 coredump_netbsd, 70 exec_setup_stack }, 71 }; 72 73 static int 74 exec_aout_modcmd(modcmd_t cmd, void *arg) 75 { 76 77 switch (cmd) { 78 case MODULE_CMD_INIT: 79 return exec_add(exec_aout_execsw, 80 __arraycount(exec_aout_execsw)); 81 82 case MODULE_CMD_FINI: 83 return exec_remove(exec_aout_execsw, 84 __arraycount(exec_aout_execsw)); 85 86 default: 87 return ENOTTY; 88 } 89 } 90 91 /* 92 * exec_aout_makecmds(): Check if it's an a.out-format executable. 93 * 94 * Given a lwp pointer and an exec package pointer, see if the referent 95 * of the epp is in a.out format. First check 'standard' magic numbers for 96 * this architecture. If that fails, try a CPU-dependent hook. 97 * 98 * This function, in the former case, or the hook, in the latter, is 99 * responsible for creating a set of vmcmds which can be used to build 100 * the process's vm space and inserting them into the exec package. 101 */ 102 103 int 104 exec_aout_makecmds(struct lwp *l, struct exec_package *epp) 105 { 106 u_long midmag, magic; 107 u_short mid; 108 int error; 109 struct exec *execp = epp->ep_hdr; 110 111 if (epp->ep_hdrvalid < sizeof(struct exec)) 112 return ENOEXEC; 113 114 midmag = ntohl(execp->a_midmag); 115 mid = (midmag >> 16) & 0x3ff; 116 magic = midmag & 0xffff; 117 118 midmag = mid << 16 | magic; 119 120 switch (midmag) { 121 case (MID_MACHINE << 16) | ZMAGIC: 122 error = exec_aout_prep_zmagic(l, epp); 123 break; 124 case (MID_MACHINE << 16) | NMAGIC: 125 error = exec_aout_prep_nmagic(l, epp); 126 break; 127 case (MID_MACHINE << 16) | OMAGIC: 128 error = exec_aout_prep_omagic(l, epp); 129 break; 130 default: 131 error = cpu_exec_aout_makecmds(l, epp); 132 } 133 134 if (error) 135 kill_vmcmds(&epp->ep_vmcmds); 136 137 return error; 138 } 139 140 /* 141 * exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package 142 * 143 * First, set of the various offsets/lengths in the exec package. 144 * 145 * Then, mark the text image busy (so it can be demand paged) or error 146 * out if this is not possible. Finally, set up vmcmds for the 147 * text, data, bss, and stack segments. 148 */ 149 150 int 151 exec_aout_prep_zmagic(struct lwp *l, struct exec_package *epp) 152 { 153 struct exec *execp = epp->ep_hdr; 154 int error; 155 156 epp->ep_taddr = AOUT_LDPGSZ; 157 epp->ep_tsize = execp->a_text; 158 epp->ep_daddr = epp->ep_taddr + execp->a_text; 159 epp->ep_dsize = execp->a_data + execp->a_bss; 160 epp->ep_entry = execp->a_entry; 161 162 error = vn_marktext(epp->ep_vp); 163 if (error) 164 return (error); 165 166 /* set up command for text segment */ 167 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(execp->a_text), 168 epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE); 169 170 /* set up command for data segment */ 171 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(execp->a_data), 172 epp->ep_daddr, epp->ep_vp, execp->a_text, 173 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 174 175 /* set up command for bss segment */ 176 if (execp->a_bss > 0) 177 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss, 178 epp->ep_daddr + execp->a_data, NULLVP, 0, 179 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 180 181 return (*epp->ep_esch->es_setup_stack)(l, epp); 182 } 183 184 /* 185 * exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's exec package 186 */ 187 188 int 189 exec_aout_prep_nmagic(struct lwp *l, struct exec_package *epp) 190 { 191 struct exec *execp = epp->ep_hdr; 192 long bsize, baddr; 193 194 epp->ep_taddr = AOUT_LDPGSZ; 195 epp->ep_tsize = execp->a_text; 196 epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, AOUT_LDPGSZ); 197 epp->ep_dsize = execp->a_data + execp->a_bss; 198 epp->ep_entry = execp->a_entry; 199 200 /* set up command for text segment */ 201 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text, 202 epp->ep_taddr, epp->ep_vp, sizeof(struct exec), 203 VM_PROT_READ|VM_PROT_EXECUTE); 204 205 /* set up command for data segment */ 206 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data, 207 epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec), 208 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 209 210 /* set up command for bss segment */ 211 baddr = round_page(epp->ep_daddr + execp->a_data); 212 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 213 if (bsize > 0) 214 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 215 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 216 217 return (*epp->ep_esch->es_setup_stack)(l, epp); 218 } 219 220 /* 221 * exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's exec package 222 */ 223 224 int 225 exec_aout_prep_omagic(struct lwp *l, struct exec_package *epp) 226 { 227 struct exec *execp = epp->ep_hdr; 228 long dsize, bsize, baddr; 229 230 epp->ep_taddr = AOUT_LDPGSZ; 231 epp->ep_tsize = execp->a_text; 232 epp->ep_daddr = epp->ep_taddr + execp->a_text; 233 epp->ep_dsize = execp->a_data + execp->a_bss; 234 epp->ep_entry = execp->a_entry; 235 236 /* set up command for text and data segments */ 237 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, 238 execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp, 239 sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 240 241 /* set up command for bss segment */ 242 baddr = round_page(epp->ep_daddr + execp->a_data); 243 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 244 if (bsize > 0) 245 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 246 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 247 248 /* 249 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize); 250 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are 251 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize' 252 * respectively to page boundaries. 253 * Compensate `ep_dsize' for the amount of data covered by the last 254 * text page. 255 */ 256 dsize = epp->ep_dsize + execp->a_text - round_page(execp->a_text); 257 epp->ep_dsize = (dsize > 0) ? dsize : 0; 258 return (*epp->ep_esch->es_setup_stack)(l, epp); 259 } 260