1 /* $NetBSD: exec_machdep.c,v 1.10 2021/09/23 15:19:03 ryo Exp $ */
2
3 /*-
4 * Copyright (c) 2014 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
34 __KERNEL_RCSID(1, "$NetBSD: exec_machdep.c,v 1.10 2021/09/23 15:19:03 ryo Exp $");
35
36 #include "opt_compat_netbsd.h"
37 #include "opt_compat_netbsd32.h"
38
39 #include <sys/param.h>
40 #include <sys/systm.h>
41 #include <sys/proc.h>
42 #include <sys/exec.h>
43 #include <sys/cprng.h>
44
45 #include <uvm/uvm_extern.h>
46
47 #include <compat/common/compat_util.h>
48 #include <sys/exec_elf.h> /* mandatory */
49
50 #ifdef COMPAT_NETBSD32
51 #include <compat/netbsd32/netbsd32_exec.h>
52 #endif
53
54 #include <aarch64/armreg.h>
55 #include <aarch64/frame.h>
56 #include <aarch64/machdep.h>
57
58 #include <arm/cpufunc.h>
59
60 #if EXEC_ELF64
61 int
aarch64_netbsd_elf64_probe(struct lwp * l,struct exec_package * epp,void * eh0,char * itp,vaddr_t * start_p)62 aarch64_netbsd_elf64_probe(struct lwp *l, struct exec_package *epp, void *eh0,
63 char *itp, vaddr_t *start_p)
64 {
65 return 0;
66 }
67 #endif
68
69 #if EXEC_ELF32
70 int
aarch64_netbsd_elf32_probe(struct lwp * l,struct exec_package * epp,void * eh0,char * itp,vaddr_t * start_p)71 aarch64_netbsd_elf32_probe(struct lwp *l, struct exec_package *epp, void *eh0,
72 char *itp, vaddr_t *start_p)
73 {
74 const Elf32_Ehdr * const eh = eh0;
75 const bool elf_aapcs_p =
76 (eh->e_flags & EF_ARM_EABIMASK) >= EF_ARM_EABI_VER4;
77
78 /* OABI not support */
79 if (!elf_aapcs_p)
80 return ENOEXEC;
81 #ifdef __AARCH64EB__
82 /* BE32 not support */
83 if ((eh->e_flags & EF_ARM_BE8) == 0)
84 return ENOEXEC;
85 #endif
86
87 /*
88 * require aarch32 feature.
89 * XXX should consider some cluster may have no aarch32?
90 */
91 if (__SHIFTOUT(l->l_cpu->ci_id.ac_aa64pfr0, ID_AA64PFR0_EL1_EL0) !=
92 ID_AA64PFR0_EL1_EL0_64_32)
93 return ENOEXEC;
94
95 /*
96 * Copy (if any) the machine_arch of the executable to the proc.
97 */
98 CTASSERT(sizeof(l->l_proc->p_md.md_march32) ==
99 sizeof(epp->ep_machine_arch));
100 if (epp->ep_machine_arch[0] != 0)
101 strlcpy(l->l_proc->p_md.md_march32, epp->ep_machine_arch,
102 sizeof(l->l_proc->p_md.md_march32));
103
104 return 0;
105 }
106 #endif
107
108 void
aarch64_setregs_ptrauth(struct lwp * l,bool randomize)109 aarch64_setregs_ptrauth(struct lwp *l, bool randomize)
110 {
111 #ifdef ARMV83_PAC
112 if (!aarch64_pac_enabled)
113 return;
114
115 if (randomize) {
116 cprng_strong(kern_cprng, l->l_md.md_ia_user,
117 sizeof(l->l_md.md_ia_user), 0);
118 cprng_strong(kern_cprng, l->l_md.md_ib_user,
119 sizeof(l->l_md.md_ib_user), 0);
120 cprng_strong(kern_cprng, l->l_md.md_da_user,
121 sizeof(l->l_md.md_da_user), 0);
122 cprng_strong(kern_cprng, l->l_md.md_db_user,
123 sizeof(l->l_md.md_db_user), 0);
124 cprng_strong(kern_cprng, l->l_md.md_ga_user,
125 sizeof(l->l_md.md_ga_user), 0);
126 } else {
127 memset(l->l_md.md_ia_user, 0,
128 sizeof(l->l_md.md_ia_user));
129 memset(l->l_md.md_ib_user, 0,
130 sizeof(l->l_md.md_ib_user));
131 memset(l->l_md.md_da_user, 0,
132 sizeof(l->l_md.md_da_user));
133 memset(l->l_md.md_db_user, 0,
134 sizeof(l->l_md.md_db_user));
135 memset(l->l_md.md_ga_user, 0,
136 sizeof(l->l_md.md_ga_user));
137 }
138 #endif
139 }
140
141 void
setregs(struct lwp * l,struct exec_package * pack,vaddr_t stack)142 setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack)
143 {
144 struct proc * const p = l->l_proc;
145 struct trapframe * const tf = lwp_trapframe(l);
146
147 aarch64_setregs_ptrauth(l, true);
148
149 p->p_flag &= ~PK_32;
150
151 /*
152 * void __start(void (*cleanup)(void), const Obj_Entry *obj,
153 * struct ps_strings *ps_strings);
154 */
155 memset(tf, 0, sizeof(*tf));
156 tf->tf_reg[2] = p->p_psstrp;
157 tf->tf_pc = pack->ep_entry;
158 tf->tf_sp = stack & -16L;
159 tf->tf_spsr = SPSR_M_EL0T;
160 }
161