1 /* $NetBSD: linux_exec_machdep.c,v 1.20 2020/09/05 16:30:10 riastradh 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 1.20 2020/09/05 16:30:10 riastradh 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 <sys/syscallargs.h> 49 50 #ifndef DEBUG_LINUX 51 #define DPRINTF(a) 52 #else 53 #define DPRINTF(a) uprintf a 54 #endif 55 56 #include <compat/linux/common/linux_types.h> 57 #include <compat/linux/common/linux_signal.h> 58 #include <compat/linux/common/linux_machdep.h> 59 #include <compat/linux/common/linux_util.h> 60 #include <compat/linux/common/linux_ioctl.h> 61 #include <compat/linux/common/linux_hdio.h> 62 #include <compat/linux/common/linux_exec.h> 63 #include <compat/linux/common/linux_errno.h> 64 #include <compat/linux/linux_syscallargs.h> 65 66 int 67 linux_exec_setup_stack(struct lwp *l, struct exec_package *epp) 68 { 69 u_long max_stack_size; 70 u_long access_linear_min, access_size; 71 u_long noaccess_linear_min, noaccess_size; 72 73 #ifndef USRSTACK32 74 #define USRSTACK32 (0x00000000ffffffffL&~PGOFSET) 75 #endif 76 77 if (epp->ep_flags & EXEC_32) { 78 epp->ep_minsaddr = USRSTACK32; 79 max_stack_size = MAXSSIZ; 80 } else { 81 epp->ep_minsaddr = USRSTACK; 82 max_stack_size = MAXSSIZ; 83 } 84 85 if (epp->ep_minsaddr > LINUX_USRSTACK) 86 epp->ep_minsaddr = LINUX_USRSTACK; 87 #ifdef DEBUG_LINUX 88 else { 89 /* 90 * Someone needs to make KERNBASE and TEXTADDR 91 * java versions < 1.4.2 need the stack to be 92 * at 0xC0000000 93 */ 94 uprintf("Cannot setup stack to 0xC0000000, " 95 "java will not work properly\n"); 96 } 97 #endif 98 epp->ep_maxsaddr = (u_long)STACK_GROW(epp->ep_minsaddr, 99 max_stack_size); 100 epp->ep_ssize = l->l_proc->p_rlimit[RLIMIT_STACK].rlim_cur; 101 102 /* 103 * set up commands for stack. note that this takes *two*, one to 104 * map the part of the stack which we can access, and one to map 105 * the part which we can't. 106 * 107 * arguably, it could be made into one, but that would require the 108 * addition of another mapping proc, which is unnecessary 109 */ 110 access_size = epp->ep_ssize; 111 access_linear_min = (u_long)STACK_ALLOC(epp->ep_minsaddr, access_size); 112 noaccess_size = max_stack_size - access_size; 113 noaccess_linear_min = (u_long)STACK_ALLOC(STACK_GROW(epp->ep_minsaddr, 114 access_size), noaccess_size); 115 if (noaccess_size > 0) { 116 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, noaccess_size, 117 noaccess_linear_min, NULLVP, 0, VM_PROT_NONE, VMCMD_STACK); 118 } 119 KASSERT(access_size > 0); 120 NEW_VMCMD2(&epp->ep_vmcmds, vmcmd_map_zero, access_size, 121 access_linear_min, NULLVP, 0, VM_PROT_READ | VM_PROT_WRITE, 122 VMCMD_STACK); 123 124 return 0; 125 } 126 127 int 128 linux_sys_set_thread_area(struct lwp *l, 129 const struct linux_sys_set_thread_area_args *uap, register_t *retval) 130 { 131 /* { 132 syscallarg(struct linux_user_desc *) desc; 133 } */ 134 135 return linux_lwp_setprivate(l, SCARG(uap, desc)); 136 } 137 138 int 139 linux_sys_get_thread_area(struct lwp *l, 140 const struct linux_sys_get_thread_area_args *uap, register_t *retval) 141 { 142 /* { 143 syscallarg(struct linux_user_desc *) desc; 144 } */ 145 146 /* glibc doesn't actually call this. */ 147 return ENOSYS; 148 } 149