1 /* $NetBSD: exec_aout.c,v 1.43 2024/12/06 16:19:41 riastradh 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 1.43 2024/12/06 16:19:41 riastradh Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/types.h> 38 39 #include <sys/exec.h> 40 #include <sys/exec_aout.h> 41 #include <sys/module.h> 42 #include <sys/proc.h> 43 #include <sys/resourcevar.h> 44 #include <sys/sdt.h> 45 #include <sys/systm.h> 46 #include <sys/vnode.h> 47 48 #include <uvm/uvm_extern.h> 49 50 MODULE(MODULE_CLASS_EXEC, exec_aout, NULL); 51 52 static struct execsw exec_aout_execsw = { 53 .es_hdrsz = sizeof(struct exec), 54 .es_makecmds = exec_aout_makecmds, 55 .u = { 56 .elf_probe_func = NULL, 57 }, 58 .es_emul = &emul_netbsd, 59 .es_prio = EXECSW_PRIO_ANY, 60 .es_arglen = 0, 61 .es_copyargs = copyargs, 62 .es_setregs = NULL, 63 .es_coredump = coredump_netbsd, 64 .es_setup_stack = exec_setup_stack, 65 }; 66 67 static int 68 exec_aout_modcmd(modcmd_t cmd, void *arg) 69 { 70 71 switch (cmd) { 72 case MODULE_CMD_INIT: 73 return exec_add(&exec_aout_execsw, 1); 74 75 case MODULE_CMD_FINI: 76 return exec_remove(&exec_aout_execsw, 1); 77 78 default: 79 return SET_ERROR(ENOTTY); 80 } 81 } 82 83 /* 84 * exec_aout_makecmds(): Check if it's an a.out-format executable. 85 * 86 * Given a lwp pointer and an exec package pointer, see if the referent 87 * of the epp is in a.out format. First check 'standard' magic numbers for 88 * this architecture. If that fails, try a CPU-dependent hook. 89 * 90 * This function, in the former case, or the hook, in the latter, is 91 * responsible for creating a set of vmcmds which can be used to build 92 * the process's vm space and inserting them into the exec package. 93 */ 94 95 int 96 exec_aout_makecmds(struct lwp *l, struct exec_package *epp) 97 { 98 u_long midmag, magic; 99 u_short mid; 100 int error; 101 struct exec *execp = epp->ep_hdr; 102 103 if (epp->ep_hdrvalid < sizeof(struct exec)) 104 return SET_ERROR(ENOEXEC); 105 106 midmag = ntohl(execp->a_midmag); 107 mid = (midmag >> 16) & 0x3ff; 108 magic = midmag & 0xffff; 109 110 midmag = mid << 16 | magic; 111 112 switch (midmag) { 113 case (MID_MACHINE << 16) | ZMAGIC: 114 error = exec_aout_prep_zmagic(l, epp); 115 break; 116 case (MID_MACHINE << 16) | NMAGIC: 117 error = exec_aout_prep_nmagic(l, epp); 118 break; 119 case (MID_MACHINE << 16) | OMAGIC: 120 error = exec_aout_prep_omagic(l, epp); 121 break; 122 default: 123 error = cpu_exec_aout_makecmds(l, epp); 124 } 125 126 if (error) 127 kill_vmcmds(&epp->ep_vmcmds); 128 else 129 epp->ep_flags &= ~EXEC_TOPDOWN_VM; 130 131 return error; 132 } 133 134 /* 135 * exec_aout_prep_zmagic(): Prepare a 'native' ZMAGIC binary's exec package 136 * 137 * First, set of the various offsets/lengths in the exec package. 138 * 139 * Then, mark the text image busy (so it can be demand paged) or error 140 * out if this is not possible. Finally, set up vmcmds for the 141 * text, data, bss, and stack segments. 142 */ 143 144 int 145 exec_aout_prep_zmagic(struct lwp *l, struct exec_package *epp) 146 { 147 struct exec *execp = epp->ep_hdr; 148 int error; 149 150 epp->ep_taddr = AOUT_LDPGSZ; 151 epp->ep_tsize = execp->a_text; 152 epp->ep_daddr = epp->ep_taddr + execp->a_text; 153 epp->ep_dsize = execp->a_data + execp->a_bss; 154 epp->ep_entry = execp->a_entry; 155 156 error = vn_marktext(epp->ep_vp); 157 if (error) 158 return (error); 159 160 /* set up command for text segment */ 161 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(execp->a_text), 162 epp->ep_taddr, epp->ep_vp, 0, VM_PROT_READ|VM_PROT_EXECUTE); 163 164 /* set up command for data segment */ 165 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_pagedvn, round_page(execp->a_data), 166 epp->ep_daddr, epp->ep_vp, execp->a_text, 167 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 168 169 /* set up command for bss segment */ 170 if (execp->a_bss > 0) 171 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, execp->a_bss, 172 epp->ep_daddr + execp->a_data, NULLVP, 0, 173 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 174 175 return (*epp->ep_esch->es_setup_stack)(l, epp); 176 } 177 178 /* 179 * exec_aout_prep_nmagic(): Prepare a 'native' NMAGIC binary's exec package 180 */ 181 182 int 183 exec_aout_prep_nmagic(struct lwp *l, struct exec_package *epp) 184 { 185 struct exec *execp = epp->ep_hdr; 186 long bsize, baddr; 187 188 epp->ep_taddr = AOUT_LDPGSZ; 189 epp->ep_tsize = execp->a_text; 190 epp->ep_daddr = roundup(epp->ep_taddr + execp->a_text, AOUT_LDPGSZ); 191 epp->ep_dsize = execp->a_data + execp->a_bss; 192 epp->ep_entry = execp->a_entry; 193 194 /* set up command for text segment */ 195 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_text, 196 epp->ep_taddr, epp->ep_vp, sizeof(struct exec), 197 VM_PROT_READ|VM_PROT_EXECUTE); 198 199 /* set up command for data segment */ 200 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, execp->a_data, 201 epp->ep_daddr, epp->ep_vp, execp->a_text + sizeof(struct exec), 202 VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 203 204 /* set up command for bss segment */ 205 baddr = round_page(epp->ep_daddr + execp->a_data); 206 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 207 if (bsize > 0) 208 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 209 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 210 211 return (*epp->ep_esch->es_setup_stack)(l, epp); 212 } 213 214 /* 215 * exec_aout_prep_omagic(): Prepare a 'native' OMAGIC binary's exec package 216 */ 217 218 int 219 exec_aout_prep_omagic(struct lwp *l, struct exec_package *epp) 220 { 221 struct exec *execp = epp->ep_hdr; 222 long dsize, bsize, baddr; 223 224 epp->ep_taddr = AOUT_LDPGSZ; 225 epp->ep_tsize = execp->a_text; 226 epp->ep_daddr = epp->ep_taddr + execp->a_text; 227 epp->ep_dsize = execp->a_data + execp->a_bss; 228 epp->ep_entry = execp->a_entry; 229 230 /* set up command for text and data segments */ 231 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_readvn, 232 execp->a_text + execp->a_data, epp->ep_taddr, epp->ep_vp, 233 sizeof(struct exec), VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 234 235 /* set up command for bss segment */ 236 baddr = round_page(epp->ep_daddr + execp->a_data); 237 bsize = epp->ep_daddr + epp->ep_dsize - baddr; 238 if (bsize > 0) 239 NEW_VMCMD(&epp->ep_vmcmds, vmcmd_map_zero, bsize, baddr, 240 NULLVP, 0, VM_PROT_READ|VM_PROT_WRITE|VM_PROT_EXECUTE); 241 242 /* 243 * Make sure (# of pages) mapped above equals (vm_tsize + vm_dsize); 244 * obreak(2) relies on this fact. Both `vm_tsize' and `vm_dsize' are 245 * computed (in execve(2)) by rounding *up* `ep_tsize' and `ep_dsize' 246 * respectively to page boundaries. 247 * Compensate `ep_dsize' for the amount of data covered by the last 248 * text page. 249 */ 250 dsize = epp->ep_dsize + execp->a_text - round_page(execp->a_text); 251 epp->ep_dsize = (dsize > 0) ? dsize : 0; 252 return (*epp->ep_esch->es_setup_stack)(l, epp); 253 } 254
Indexes created Sat Sep 20 22:09:52 GMT 2025