1 /* $NetBSD: linux_exec.c,v 1.53 2001/09/18 19:36:39 jdolecek Exp $ */ 2 3 /*- 4 * Copyright (c) 1994, 1995, 1998, 2000 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 and 9 * Thor Lancelot Simon. 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 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #include <sys/param.h> 41 #include <sys/systm.h> 42 #include <sys/kernel.h> 43 #include <sys/proc.h> 44 #include <sys/malloc.h> 45 #include <sys/namei.h> 46 #include <sys/vnode.h> 47 #include <sys/mount.h> 48 #include <sys/exec.h> 49 #include <sys/exec_elf.h> 50 51 #include <sys/mman.h> 52 #include <sys/syscallargs.h> 53 54 #include <machine/cpu.h> 55 #include <machine/reg.h> 56 57 #include <compat/linux/common/linux_types.h> 58 #include <compat/linux/common/linux_signal.h> 59 #include <compat/linux/common/linux_util.h> 60 #include <compat/linux/common/linux_exec.h> 61 #include <compat/linux/common/linux_machdep.h> 62 63 #include <compat/linux/linux_syscallargs.h> 64 #include <compat/linux/linux_syscall.h> 65 #include <compat/linux/common/linux_misc.h> 66 #include <compat/linux/common/linux_errno.h> 67 #include <compat/linux/common/linux_emuldata.h> 68 69 extern struct sysent linux_sysent[]; 70 extern const char * const linux_syscallnames[]; 71 extern char linux_sigcode[], linux_esigcode[]; 72 #ifndef __HAVE_SYSCALL_INTERN 73 void syscall __P((void)); 74 #endif 75 76 static void linux_e_proc_exec __P((struct proc *, struct exec_package *)); 77 static void linux_e_proc_fork __P((struct proc *, struct proc *)); 78 static void linux_e_proc_exit __P((struct proc *)); 79 static void linux_e_proc_init __P((struct proc *, struct vmspace *)); 80 81 /* 82 * Execve(2). Just check the alternate emulation path, and pass it on 83 * to the NetBSD execve(). 84 */ 85 int 86 linux_sys_execve(p, v, retval) 87 struct proc *p; 88 void *v; 89 register_t *retval; 90 { 91 struct linux_sys_execve_args /* { 92 syscallarg(const char *) path; 93 syscallarg(char **) argv; 94 syscallarg(char **) envp; 95 } */ *uap = v; 96 struct sys_execve_args ap; 97 caddr_t sg; 98 99 sg = stackgap_init(p->p_emul); 100 CHECK_ALT_EXIST(p, &sg, SCARG(uap, path)); 101 102 SCARG(&ap, path) = SCARG(uap, path); 103 SCARG(&ap, argp) = SCARG(uap, argp); 104 SCARG(&ap, envp) = SCARG(uap, envp); 105 106 return sys_execve(p, &ap, retval); 107 } 108 109 /* 110 * Emulation switch. 111 */ 112 const struct emul emul_linux = { 113 "linux", 114 "/emul/linux", 115 #ifndef __HAVE_MINIMAL_EMUL 116 0, 117 (int*)native_to_linux_errno, 118 LINUX_SYS_syscall, 119 LINUX_SYS_MAXSYSCALL, 120 #endif 121 linux_sysent, 122 linux_syscallnames, 123 linux_sendsig, 124 linux_trapsignal, 125 linux_sigcode, 126 linux_esigcode, 127 linux_setregs, 128 linux_e_proc_exec, 129 linux_e_proc_fork, 130 linux_e_proc_exit, 131 #ifdef __HAVE_SYSCALL_INTERN 132 linux_syscall_intern, 133 #else 134 syscall, 135 #endif 136 }; 137 138 static void 139 linux_e_proc_init(p, vmspace) 140 struct proc *p; 141 struct vmspace *vmspace; 142 { 143 if (!p->p_emuldata) { 144 /* allocate new Linux emuldata */ 145 MALLOC(p->p_emuldata, void *, sizeof(struct linux_emuldata), 146 M_EMULDATA, M_WAITOK); 147 } 148 149 memset(p->p_emuldata, '\0', sizeof(struct linux_emuldata)); 150 151 /* Set the process idea of the break to the real value */ 152 ((struct linux_emuldata*)(p->p_emuldata))->p_break = 153 vmspace->vm_daddr + ctob(vmspace->vm_dsize); 154 } 155 156 /* 157 * Allocate per-process structures. Called when executing Linux 158 * process. We can reuse the old emuldata - if it's not null, 159 * the executed process is of same emulation as original forked one. 160 */ 161 static void 162 linux_e_proc_exec(p, epp) 163 struct proc *p; 164 struct exec_package *epp; 165 { 166 /* exec, use our vmspace */ 167 linux_e_proc_init(p, p->p_vmspace); 168 } 169 170 /* 171 * Emulation per-process exit hook. 172 */ 173 static void 174 linux_e_proc_exit(p) 175 struct proc *p; 176 { 177 /* free Linux emuldata and set the pointer to null */ 178 FREE(p->p_emuldata, M_EMULDATA); 179 p->p_emuldata = NULL; 180 } 181 182 /* 183 * Emulation fork hook. 184 */ 185 static void 186 linux_e_proc_fork(p, parent) 187 struct proc *p, *parent; 188 { 189 /* 190 * It could be desirable to copy some stuff from parent's 191 * emuldata. We don't need anything like that for now. 192 * So just allocate new emuldata for the new process. 193 */ 194 p->p_emuldata = NULL; 195 196 /* fork, use parent's vmspace (our vmspace may not be setup yet) */ 197 linux_e_proc_init(p, parent->p_vmspace); 198 } 199