1 /* $NetBSD: linux32_exec.c,v 1.18 2009/03/14 21:04:18 dsl Exp $ */ 2 3 /*- 4 * Copyright (c) 1994-2007 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas, Frank van der Linden, Eric Haszlakiewicz, 9 * Thor Lancelot Simon, and Emmanuel Dreyfus. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: linux32_exec.c,v 1.18 2009/03/14 21:04:18 dsl Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/kernel.h> 39 #include <sys/proc.h> 40 #include <sys/malloc.h> 41 #include <sys/namei.h> 42 #include <sys/vnode.h> 43 #include <sys/mount.h> 44 #include <sys/exec.h> 45 #include <sys/exec_elf.h> 46 47 #include <sys/mman.h> 48 #include <sys/syscallargs.h> 49 #include <sys/ptrace.h> /* For proc_reparent() */ 50 51 #include <uvm/uvm_extern.h> 52 53 #include <sys/cpu.h> 54 #include <machine/reg.h> 55 56 #include <compat/linux/common/linux_types.h> 57 #include <compat/linux/common/linux_emuldata.h> 58 59 #include <compat/linux32/common/linux32_exec.h> 60 #include <compat/linux32/common/linux32_types.h> 61 #include <compat/linux32/common/linux32_signal.h> 62 #include <compat/linux32/common/linux32_machdep.h> 63 64 #include <compat/linux32/linux32_syscallargs.h> 65 #include <compat/linux32/linux32_syscall.h> 66 67 extern char linux32_sigcode[1]; 68 extern char linux32_rt_sigcode[1]; 69 extern char linux32_esigcode[1]; 70 71 extern struct sysent linux32_sysent[]; 72 extern const char * const linux32_syscallnames[]; 73 74 static void linux32_e_proc_exec(struct proc *, struct exec_package *); 75 static void linux32_e_proc_fork(struct proc *, struct proc *, int); 76 static void linux32_e_proc_exit(struct proc *); 77 static void linux32_e_proc_init(struct proc *, struct proc *, int); 78 79 #ifdef LINUX32_NPTL 80 void linux32_userret(void); 81 void linux_nptl_proc_fork(struct proc *, struct proc *, void (*luserret)(void)); 82 void linux_nptl_proc_exit(struct proc *); 83 void linux_nptl_proc_init(struct proc *, struct proc *); 84 #endif 85 86 /* 87 * Emulation switch. 88 */ 89 90 struct uvm_object *emul_linux32_object; 91 92 struct emul emul_linux32 = { 93 "linux32", 94 "/emul/linux32", 95 #ifndef __HAVE_MINIMAL_EMUL 96 0, 97 NULL, 98 LINUX32_SYS_syscall, 99 LINUX32_SYS_NSYSENT, 100 #endif 101 linux32_sysent, 102 linux32_syscallnames, 103 linux32_sendsig, 104 trapsignal, 105 NULL, 106 linux32_sigcode, 107 linux32_esigcode, 108 &emul_linux32_object, 109 linux32_setregs, 110 linux32_e_proc_exec, 111 linux32_e_proc_fork, 112 linux32_e_proc_exit, 113 NULL, 114 NULL, 115 linux32_syscall_intern, 116 NULL, 117 NULL, 118 netbsd32_vm_default_addr, 119 NULL, 120 NULL, 121 0, 122 NULL 123 }; 124 125 static void 126 linux32_e_proc_init(struct proc *p, struct proc *parent, int forkflags) 127 { 128 struct linux_emuldata *e = p->p_emuldata; 129 struct linux_emuldata_shared *s; 130 struct linux_emuldata *ep = NULL; 131 132 if (!e) { 133 /* allocate new Linux emuldata */ 134 e = malloc(sizeof(struct linux_emuldata), 135 M_EMULDATA, M_WAITOK); 136 } else { 137 mutex_enter(proc_lock); 138 e->s->refs--; 139 if (e->s->refs == 0) 140 free(e->s, M_EMULDATA); 141 mutex_exit(proc_lock); 142 } 143 144 memset(e, '\0', sizeof(struct linux_emuldata)); 145 146 e->proc = p; 147 148 if (parent) 149 ep = parent->p_emuldata; 150 151 if (forkflags & FORK_SHAREVM) { 152 mutex_enter(proc_lock); 153 #ifdef DIAGNOSTIC 154 if (ep == NULL) { 155 killproc(p, "FORK_SHAREVM while emuldata is NULL\n"); 156 mutex_exit(proc_lock); 157 return; 158 } 159 #endif 160 s = ep->s; 161 s->refs++; 162 } else { 163 struct vmspace *vm; 164 165 s = malloc(sizeof(struct linux_emuldata_shared), 166 M_EMULDATA, M_WAITOK); 167 s->refs = 1; 168 169 /* 170 * Set the process idea of the break to the real value. 171 * For fork, we use parent's vmspace since our's 172 * is not setup at the time of this call and is going 173 * to be copy of parent's anyway. For exec, just 174 * use our own vmspace. 175 */ 176 vm = (parent) ? parent->p_vmspace : p->p_vmspace; 177 s->p_break = (char *)vm->vm_daddr + ctob(vm->vm_dsize); 178 179 /* 180 * Linux threads are emulated as NetBSD processes (not lwp) 181 * We use native PID for Linux TID. The Linux TID is the 182 * PID of the first process in the group. It is stored 183 * here 184 */ 185 s->group_pid = p->p_pid; 186 187 /* 188 * Initialize the list of threads in the group 189 */ 190 LIST_INIT(&s->threads); 191 192 s->xstat = 0; 193 s->flags = 0; 194 mutex_enter(proc_lock); 195 } 196 197 e->s = s; 198 199 /* 200 * Add this thread in the group thread list 201 */ 202 LIST_INSERT_HEAD(&s->threads, e, threads); 203 mutex_exit(proc_lock); 204 205 #ifdef LINUX32_NPTL 206 linux_nptl_proc_init(p, parent); 207 #endif /* LINUX32_NPTL */ 208 209 p->p_emuldata = e; 210 } 211 212 /* 213 * Allocate new per-process structures. Called when executing Linux 214 * process. We can reuse the old emuldata - if it's not null, 215 * the executed process is of same emulation as original forked one. 216 */ 217 static void 218 linux32_e_proc_exec(struct proc *p, struct exec_package *epp) 219 { 220 /* exec, use our vmspace */ 221 linux32_e_proc_init(p, NULL, 0); 222 } 223 224 /* 225 * Emulation per-process exit hook. 226 */ 227 static void 228 linux32_e_proc_exit(struct proc *p) 229 { 230 struct linux_emuldata *e = p->p_emuldata; 231 232 #ifdef LINUX32_NPTL 233 linux_nptl_proc_exit(p); 234 #endif /* LINUX32_NPTL */ 235 236 /* Remove the thread for the group thread list */ 237 mutex_enter(proc_lock); 238 LIST_REMOVE(e, threads); 239 240 /* free Linux emuldata and set the pointer to null */ 241 e->s->refs--; 242 if (e->s->refs == 0) 243 free(e->s, M_EMULDATA); 244 p->p_emuldata = NULL; 245 mutex_exit(proc_lock); 246 free(e, M_EMULDATA); 247 } 248 249 /* 250 * Emulation fork hook. 251 */ 252 static void 253 linux32_e_proc_fork(struct proc *p, struct proc *parent, int forkflags) 254 { 255 /* 256 * The new process might share some vmspace-related stuff 257 * with parent, depending on fork flags (CLONE_VM et.al). 258 * Force allocation of new base emuldata, and share the 259 * VM-related parts only if necessary. 260 */ 261 p->p_emuldata = NULL; 262 linux32_e_proc_init(p, parent, forkflags); 263 264 #ifdef LINUX32_NPTL 265 linux_nptl_proc_fork(p, parent, linux32_userret); 266 #endif 267 268 return; 269 } 270 271 #ifdef LINUX32_NPTL 272 void 273 linux32_userret(void) 274 { 275 struct lwp *l = curlwp; 276 struct proc *p = l->l_proc; 277 struct linux_emuldata *led = p->p_emuldata; 278 int error; 279 280 /* LINUX_CLONE_CHILD_SETTID: copy child's TID to child's memory */ 281 if (led->clone_flags & LINUX_CLONE_CHILD_SETTID) { 282 if ((error = copyout(&l->l_proc->p_pid, 283 led->child_tidptr, sizeof(l->l_proc->p_pid))) != 0) 284 printf("linux32_userret: LINUX_CLONE_CHILD_SETTID " 285 "failed (led->child_tidptr = %p, p->p_pid = %d)\n", 286 led->child_tidptr, p->p_pid); 287 } 288 289 /* LINUX_CLONE_SETTLS: allocate a new TLS */ 290 if (led->clone_flags & LINUX_CLONE_SETTLS) { 291 if (linux32_set_newtls(l, linux32_get_newtls(l)) != 0) 292 printf("linux32_userret: linux32_set_tls failed"); 293 } 294 295 return; 296 } 297 #endif /* LINUX32_NPTL */ 298