1 /* $NetBSD: cpu_exec.c,v 1.12 2020/11/12 01:03:22 rin Exp $ */ 2 3 /*- 4 * Copyright (c) 2012 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Matt Thomas of 3am Software Foundry. 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: cpu_exec.c,v 1.12 2020/11/12 01:03:22 rin Exp $"); 34 35 #include "opt_compat_netbsd.h" 36 37 #include <sys/param.h> 38 #include <sys/systm.h> 39 #include <sys/proc.h> 40 #include <sys/exec.h> 41 42 #include <uvm/uvm_extern.h> 43 44 #include <compat/common/compat_util.h> 45 #include <sys/exec_elf.h> /* mandatory */ 46 47 #include <arm/locore.h> 48 49 #if EXEC_ELF32 50 int 51 arm_netbsd_elf32_probe(struct lwp *l, struct exec_package *epp, void *eh0, 52 char *itp, vaddr_t *start_p) 53 { 54 const char *itp_suffix = NULL; 55 const Elf_Ehdr * const eh = eh0; 56 const bool elf_aapcs_p = 57 (eh->e_flags & EF_ARM_EABIMASK) >= EF_ARM_EABI_VER4; 58 #if defined(COMPAT_NETBSD32) || defined(MODULAR) 59 const bool netbsd32_p = (epp->ep_esch->es_emul != &emul_netbsd); 60 #else 61 const bool netbsd32_p = false; 62 #endif 63 #ifdef __ARM_EABI__ 64 const bool aapcs_p = true; 65 #else 66 const bool aapcs_p = false; 67 #endif 68 #ifdef __ARMEB__ 69 const bool be8_p = (eh->e_flags & EF_ARM_BE8) != 0; 70 71 /* 72 * If the BE-8 model is supported, CPSR[7] will be clear. 73 * If the BE-32 model is supported, CPSR[7] will be set. 74 */ 75 register_t ctl = armreg_sctlr_read(); 76 if (((ctl & CPU_CONTROL_BEND_ENABLE) != 0) == be8_p) 77 return ENOEXEC; 78 #endif /* __ARMEB__ */ 79 80 /* 81 * This is subtle. If we are netbsd32, then we don't want to match the 82 * same ABI as the kernel. If we aren't (netbsd32 == false), then we 83 * don't want to be different from the kernel's ABI. 84 * true true true ENOEXEC 85 * true false true 0 86 * true true false 0 87 * true false false ENOEXEC 88 * false true true 0 89 * false false true ENOEXEC 90 * false true false ENOEXEC 91 * false false false 0 92 */ 93 if (netbsd32_p ^ elf_aapcs_p ^ aapcs_p) 94 return ENOEXEC; 95 96 if (netbsd32_p) 97 itp_suffix = (elf_aapcs_p) ? "eabi" : "oabi"; 98 99 if (itp_suffix != NULL) 100 (void)compat_elf_check_interp(epp, itp, itp_suffix); 101 102 /* 103 * Copy (if any) the machine_arch of the executable to the proc. 104 */ 105 if (epp->ep_machine_arch[0] != 0) { 106 strlcpy(l->l_proc->p_md.md_march, epp->ep_machine_arch, 107 sizeof(l->l_proc->p_md.md_march)); 108 } 109 110 /* 111 * If we are AAPCS (EABI) and armv6/armv7, we want alignment faults 112 * to be off. 113 */ 114 if (aapcs_p && (CPU_IS_ARMV7_P() || CPU_IS_ARMV6_P())) { 115 l->l_md.md_flags |= MDLWP_NOALIGNFLT; 116 } else { 117 l->l_md.md_flags &= ~MDLWP_NOALIGNFLT; 118 } 119 return 0; 120 } 121 #endif 122