1 /* $NetBSD: linux_exec_machdep.c,v 1.18 2017/08/12 07:21:57 maxv Exp $ */ 2 3 /*- 4 * Copyright (c) 2004 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. 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: linux_exec_machdep.c,v 1.18 2017/08/12 07:21:57 maxv Exp $"); 34 35 #if defined(_KERNEL_OPT) 36 #include "opt_user_ldt.h" 37 #endif 38 39 #include <sys/param.h> 40 #include <sys/systm.h> 41 #include <sys/resource.h> 42 #include <sys/proc.h> 43 #include <sys/conf.h> 44 #include <sys/exec.h> 45 #include <sys/exec_elf.h> 46 #include <sys/vnode.h> 47 #include <sys/lwp.h> 48 49 #include <sys/cpu.h> 50 #include <machine/vmparam.h> 51 52 #include <uvm/uvm.h> 53 54 #include <sys/syscallargs.h> 55 56 #ifndef DEBUG_LINUX 57 #define DPRINTF(a) 58 #else 59 #define DPRINTF(a) uprintf a 60 #endif 61 62 #include <compat/linux/common/linux_types.h> 63 #include <compat/linux/common/linux_signal.h> 64 #include <compat/linux/common/linux_machdep.h> 65 #include <compat/linux/common/linux_util.h> 66 #include <compat/linux/common/linux_ioctl.h> 67 #include <compat/linux/common/linux_hdio.h> 68 #include <compat/linux/common/linux_exec.h> 69 #include <compat/linux/common/linux_errno.h> 70 #include <compat/linux/linux_syscallargs.h> 71 72 int 73 linux_exec_setup_stack(struct lwp *l, struct exec_package *epp) 74 { 75 u_long max_stack_size; 76 u_long access_linear_min, access_size; 77 u_long noaccess_linear_min, noaccess_size; 78 79 #ifndef USRSTACK32 80 #define USRSTACK32 (0x00000000ffffffffL&~PGOFSET) 81 #endif 82 83 if (epp->ep_flags & EXEC_32) { 84 epp->ep_minsaddr = USRSTACK32; 85 max_stack_size = MAXSSIZ; 86 } else { 87 epp->ep_minsaddr = USRSTACK; 88 max_stack_size = MAXSSIZ; 89 } 90 91 if (epp->ep_minsaddr > LINUX_USRSTACK) 92 epp->ep_minsaddr = LINUX_USRSTACK; 93 #ifdef DEBUG_LINUX 94 else { 95 /* 96 * Someone needs to make KERNBASE and TEXTADDR 97 * java versions < 1.4.2 need the stack to be 98 * at 0xC0000000 99 */ 100 uprintf("Cannot setup stack to 0xC0000000, " 101 "java will not work properly\n"); 102 } 103 #endif 104 epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr, 105 max_stack_size); 106 epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur; 107 108 /* 109 * set up commands for stack. note that this takes *two*, one to 110 * map the part of the stack which we can access, and one to map 111 * the part which we can't. 112 * 113 * arguably, it could be made into one, but that would require the 114 * addition of another mapping proc, which is unnecessary 115 */ 116 access_size = epp->ep_ssize; 117 access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size); 118 noaccess_size = max_stack_size - access_size; 119 noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 120 access_size), noaccess_size); 121 if (noaccess_size > 0) { 122 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size, 123 noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK); 124 } 125 KASSERT(access_size > 0); 126 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size, 127 access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE, 128 VMCMD_STACK); 129 130 return 0; 131 } 132 133 int 134 linux_sys_set_thread_area(struct lwp *l, 135 const struct linux_sys_set_thread_area_args *uap, register_t *retval) 136 { 137 /* { 138 syscallarg(struct linux_user_desc *) desc; 139 } */ 140 141 return linux_lwp_setprivate(l, SCARG(uap, desc)); 142 } 143 144 int 145 linux_sys_get_thread_area(struct lwp *l, 146 const struct linux_sys_get_thread_area_args *uap, register_t *retval) 147 { 148 /* { 149 syscallarg(struct linux_user_desc *) desc; 150 } */ 151 152 /* glibc doesn't actually call this. */ 153 return ENOSYS; 154 } 155