1 /* $NetBSD: linux_exec_machdep.c,v 1.19 2020/07/19 13:55:08 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 1.19 2020/07/19 13:55:08 maxv Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/resource.h> 38 #include <sys/proc.h> 39 #include <sys/conf.h> 40 #include <sys/exec.h> 41 #include <sys/exec_elf.h> 42 #include <sys/vnode.h> 43 #include <sys/lwp.h> 44 45 #include <sys/cpu.h> 46 #include <machine/vmparam.h> 47 48 #include <uvm/uvm.h> 49 50 #include <sys/syscallargs.h> 51 52 #ifndef DEBUG_LINUX 53 #define DPRINTF(a) 54 #else 55 #define DPRINTF(a) uprintf a 56 #endif 57 58 #include <compat/linux/common/linux_types.h> 59 #include <compat/linux/common/linux_signal.h> 60 #include <compat/linux/common/linux_machdep.h> 61 #include <compat/linux/common/linux_util.h> 62 #include <compat/linux/common/linux_ioctl.h> 63 #include <compat/linux/common/linux_hdio.h> 64 #include <compat/linux/common/linux_exec.h> 65 #include <compat/linux/common/linux_errno.h> 66 #include <compat/linux/linux_syscallargs.h> 67 68 int 69 linux_exec_setup_stack(struct lwp *l, struct exec_package *epp) 70 { 71 u_long max_stack_size; 72 u_long access_linear_min, access_size; 73 u_long noaccess_linear_min, noaccess_size; 74 75 #ifndef USRSTACK32 76 #define USRSTACK32 (0x00000000ffffffffL&~PGOFSET) 77 #endif 78 79 if (epp->ep_flags & EXEC_32) { 80 epp->ep_minsaddr = USRSTACK32; 81 max_stack_size = MAXSSIZ; 82 } else { 83 epp->ep_minsaddr = USRSTACK; 84 max_stack_size = MAXSSIZ; 85 } 86 87 if (epp->ep_minsaddr > LINUX_USRSTACK) 88 epp->ep_minsaddr = LINUX_USRSTACK; 89 #ifdef DEBUG_LINUX 90 else { 91 /* 92 * Someone needs to make KERNBASE and TEXTADDR 93 * java versions < 1.4.2 need the stack to be 94 * at 0xC0000000 95 */ 96 uprintf("Cannot setup stack to 0xC0000000, " 97 "java will not work properly\n"); 98 } 99 #endif 100 epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr, 101 max_stack_size); 102 epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur; 103 104 /* 105 * set up commands for stack. note that this takes *two*, one to 106 * map the part of the stack which we can access, and one to map 107 * the part which we can't. 108 * 109 * arguably, it could be made into one, but that would require the 110 * addition of another mapping proc, which is unnecessary 111 */ 112 access_size = epp->ep_ssize; 113 access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size); 114 noaccess_size = max_stack_size - access_size; 115 noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 116 access_size), noaccess_size); 117 if (noaccess_size > 0) { 118 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size, 119 noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK); 120 } 121 KASSERT(access_size > 0); 122 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size, 123 access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE, 124 VMCMD_STACK); 125 126 return 0; 127 } 128 129 int 130 linux_sys_set_thread_area(struct lwp *l, 131 const struct linux_sys_set_thread_area_args *uap, register_t *retval) 132 { 133 /* { 134 syscallarg(struct linux_user_desc *) desc; 135 } */ 136 137 return linux_lwp_setprivate(l, SCARG(uap, desc)); 138 } 139 140 int 141 linux_sys_get_thread_area(struct lwp *l, 142 const struct linux_sys_get_thread_area_args *uap, register_t *retval) 143 { 144 /* { 145 syscallarg(struct linux_user_desc *) desc; 146 } */ 147 148 /* glibc doesn't actually call this. */ 149 return ENOSYS; 150 } 151