1/* $NetBSD: linux_exec_powerpc.c,v 1.25 2021/09/07 11:43:04 riastradh Exp $ */ 2 3/*- 4 * Copyright (c) 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Emmanuel Dreyfus. 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/* 33 * From NetBSD's sys/compat/arch/alpha/linux_exec_alpha.c, with some 34 * powerpc add-ons (ifdef LINUX_SHIFT). 35 * 36 * This code is to be common to alpha and powerpc. If it works on alpha, it 37 * should be moved to common/linux_exec_elf32.c. Beware that it needs 38 * LINUX_ELF_AUX_ENTRIES in arch/<arch>/linux_exec.h to also be moved to common 39 * 40 * Emmanuel Dreyfus <p99dreyf@criens.u-psud.fr> 41 */ 42 43#include <sys/cdefs.h> 44__KERNEL_RCSID(0, "$NetBSD: linux_exec_powerpc.c,v 1.25 2021/09/07 11:43:04 riastradh Exp $"); 45 46#define ELFSIZE 32 47 48#include <sys/param.h> 49#include <sys/systm.h> 50#include <sys/kernel.h> 51#include <sys/proc.h> 52#include <sys/exec.h> 53#include <sys/exec_elf.h> 54#include <sys/resourcevar.h> 55#include <sys/kauth.h> 56 57#include <uvm/uvm_extern.h> 58 59#include <compat/linux/common/linux_exec.h> 60 61/* 62 * Alpha and PowerPC specific linux copyargs function. 63 */ 64int 65ELFNAME2(linux,copyargs)(struct lwp *l, struct exec_package *pack, 66 struct ps_strings *arginfo, char **stackp, 67 void *argp) 68{ 69 size_t len; 70 AuxInfo ai[LINUX_ELF_AUX_ENTRIES], *a; 71 struct elf_args *ap; 72 int error; 73 74#ifdef LINUX_SHIFT 75 /* 76 * Seems that PowerPC Linux binaries expect argc to start on a 16 bytes 77 * aligned address. And we need one more 16 byte shift if it was already 78 * 16 bytes aligned, 79 */ 80 *stackp = (char *)(((unsigned long)*stackp - 1) & ~LINUX_SHIFT); 81#endif 82 83 if ((error = copyargs(l, pack, arginfo, stackp, argp)) != 0) 84 return error; 85 86#ifdef LINUX_SHIFT 87 /* 88 * From Linux's arch/ppc/kernel/process.c:shove_aux_table(). GNU ld.so 89 * expects the ELF auxiliary table to start on a 16 bytes boundary on 90 * the PowerPC. 91 */ 92 *stackp = (char *)(((unsigned long)(*stackp) + LINUX_SHIFT) 93 & ~LINUX_SHIFT); 94#endif 95 96 memset(ai, 0, sizeof(ai)); 97 98 a = ai; 99 100 /* 101 * Push extra arguments on the stack needed by dynamically 102 * linked binaries. 103 */ 104 if ((ap = (struct elf_args *)pack->ep_emul_arg)) { 105#if 1 106 /* 107 * The exec_package doesn't have a proc pointer and it's not 108 * exactly trivial to add one since the credentials are 109 * changing. XXX Linux uses curlwp's credentials. 110 * Why can't we use them too? XXXad we do, what's different? 111 */ 112 a->a_type = LINUX_AT_EGID; 113 a->a_v = kauth_cred_getegid(l->l_cred); 114 a++; 115 116 a->a_type = LINUX_AT_GID; 117 a->a_v = kauth_cred_getgid(l->l_cred); 118 a++; 119 120 a->a_type = LINUX_AT_EUID; 121 a->a_v = kauth_cred_geteuid(l->l_cred); 122 a++; 123 124 a->a_type = LINUX_AT_UID; 125 a->a_v = kauth_cred_getuid(l->l_cred); 126 a++; 127#endif 128 129 a->a_type = AT_ENTRY; 130 a->a_v = ap->arg_entry; 131 a++; 132 133 a->a_type = AT_FLAGS; 134 a->a_v = 0; 135 a++; 136 137 a->a_type = AT_BASE; 138 a->a_v = ap->arg_interp; 139 a++; 140 141 a->a_type = AT_PHNUM; 142 a->a_v = ap->arg_phnum; 143 a++; 144 145 a->a_type = AT_PHENT; 146 a->a_v = ap->arg_phentsize; 147 a++; 148 149 a->a_type = AT_PHDR; 150 a->a_v = ap->arg_phaddr; 151 a++; 152 153 a->a_type = LINUX_AT_CLKTCK; 154 a->a_v = LINUX_CLOCKS_PER_SEC; 155 a++; 156 157 a->a_type = AT_PAGESZ; 158 a->a_v = PAGE_SIZE; 159 a++; 160 161 a->a_type = LINUX_AT_HWCAP; 162 a->a_v = LINUX_ELF_HWCAP; 163 a++; 164 165 exec_free_emul_arg(pack); 166 } 167 168 a->a_type = AT_NULL; 169 a->a_v = 0; 170 a++; 171 172 len = (a - ai) * sizeof(AuxInfo); 173 174 if ((error = copyout(ai, *stackp, len)) != 0) 175 return error; 176 *stackp += len; 177 return 0; 178} 179