1 /* $NetBSD: linux32_exec_elf32.c,v 1.23 2021/11/26 08:56:29 ryo Exp $ */
2
3 /*-
4 * Copyright (c) 1995, 1998, 2000, 2001,2006 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, Frank van der Linden, Eric Haszlakiewicz and
9 * Emmanuel Dreyfus.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 * notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 * notice, this list of conditions and the following disclaimer in the
18 * documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33 #include <sys/cdefs.h>
34 __KERNEL_RCSID(0, "$NetBSD: linux32_exec_elf32.c,v 1.23 2021/11/26 08:56:29 ryo Exp $");
35
36 #define ELFSIZE 32
37
38 #include <sys/param.h>
39 #include <sys/systm.h>
40 #include <sys/proc.h>
41 #include <sys/vnode.h>
42 #include <sys/exec.h>
43 #include <sys/exec_elf.h>
44 #include <sys/kauth.h>
45 #include <sys/kernel.h>
46 #include <sys/resourcevar.h>
47 #include <sys/signal.h>
48 #include <sys/signalvar.h>
49 #include <sys/cprng.h>
50
51 #include <compat/linux/common/linux_exec.h>
52 #include <compat/netbsd32/netbsd32.h>
53 #include <compat/netbsd32/netbsd32_exec.h>
54 #include <compat/linux32/common/linux32_exec.h>
55
56 #ifndef __aarch64__
57 #include <machine/cpuvar.h>
58 #endif
59 #include <machine/frame.h>
60
61 #ifdef DEBUG_LINUX
62 #define DPRINTF(a) uprintf a
63 #else
64 #define DPRINTF(a)
65 #endif
66
67 int linux32_copyinargs(struct exec_package *, struct ps_strings *,
68 void *, size_t, const void *, const void *);
69
70 int
ELFNAME2(linux32,probe)71 ELFNAME2(linux32,probe)(struct lwp *l, struct exec_package *epp,
72 void *eh, char *itp, vaddr_t *pos)
73 {
74 int error;
75
76 if (((error = ELFNAME2(linux,signature)(l, epp, eh, itp)) != 0) &&
77 #ifdef LINUX32_GCC_SIGNATURE
78 ((error = ELFNAME2(linux,gcc_signature)(l, epp, eh)) != 0) &&
79 #endif
80 #ifdef LINUX32_ATEXIT_SIGNATURE
81 ((error = ELFNAME2(linux,atexit_signature)(l, epp, eh)) != 0) &&
82 #endif
83 #ifdef LINUX32_DEBUGLINK_SIGNATURE
84 ((error = ELFNAME2(linux,debuglink_signature)(l, epp, eh)) != 0) &&
85 #endif
86 #ifdef LINUX32_GO_RT0_SIGNATURE
87 ((error = ELFNAME2(linux,go_rt0_signature)(l, epp, eh)) != 0) &&
88 #endif
89 1)
90 return error;
91
92 if (itp) {
93 if ((error = emul_find_interp(l, epp, itp)))
94 return (error);
95 }
96 #if 0
97 DPRINTF(("linux32_probe: returning 0\n"));
98 #endif
99
100 epp->ep_flags |= EXEC_32 | EXEC_FORCEAUX;
101 epp->ep_vm_minaddr = exec_vm_minaddr(VM_MIN_ADDRESS);
102 epp->ep_vm_maxaddr = USRSTACK32;
103
104 return 0;
105 }
106
107 /*
108 * Copy arguments onto the stack in the normal way, but add some
109 * extra information in case of dynamic binding.
110 */
111 int
linux32_elf32_copyargs(struct lwp * l,struct exec_package * pack,struct ps_strings * arginfo,char ** stackp,void * argp)112 linux32_elf32_copyargs(struct lwp *l, struct exec_package *pack,
113 struct ps_strings *arginfo, char **stackp, void *argp)
114 {
115 struct linux32_extra_stack_data esd, *esdp;
116 Aux32Info *a, *ai __diagused;
117 struct elf_args *ap;
118 struct vattr *vap;
119 int error;
120
121 if ((error = netbsd32_copyargs(l, pack, arginfo, stackp, argp)) != 0)
122 return error;
123
124 esdp = (struct linux32_extra_stack_data *)(*stackp); /* userspace */
125
126 memset(&esd, 0, sizeof(esd));
127 ai = a = esd.ai;
128
129 /*
130 * Push extra arguments on the stack needed by dynamically
131 * linked binaries and static binaries as well.
132 */
133
134 a->a_type = AT_PAGESZ;
135 a->a_v = PAGE_SIZE;
136 a++;
137
138 if ((ap = (struct elf_args *)pack->ep_emul_arg)) {
139
140 a->a_type = AT_PHDR;
141 a->a_v = ap->arg_phaddr;
142 a++;
143
144 a->a_type = AT_PHENT;
145 a->a_v = ap->arg_phentsize;
146 a++;
147
148 a->a_type = AT_PHNUM;
149 a->a_v = ap->arg_phnum;
150 a++;
151
152 a->a_type = AT_BASE;
153 a->a_v = ap->arg_interp;
154 a++;
155
156 a->a_type = AT_FLAGS;
157 a->a_v = 0;
158 a++;
159
160 a->a_type = AT_ENTRY;
161 a->a_v = ap->arg_entry;
162 a++;
163
164 exec_free_emul_arg(pack);
165 }
166
167 /* Linux-specific items */
168 a->a_type = LINUX_AT_CLKTCK;
169 a->a_v = hz;
170 a++;
171
172 vap = pack->ep_vap;
173
174 a->a_type = LINUX_AT_UID;
175 a->a_v = kauth_cred_getuid(l->l_cred);
176 a++;
177
178 a->a_type = LINUX_AT_EUID;
179 a->a_v = ((vap->va_mode & S_ISUID) ?
180 vap->va_uid : kauth_cred_geteuid(l->l_cred));
181 a++;
182
183 a->a_type = LINUX_AT_GID;
184 a->a_v = kauth_cred_getgid(l->l_cred);
185 a++;
186
187 a->a_type = LINUX_AT_EGID;
188 a->a_v = ((vap->va_mode & S_ISGID) ?
189 vap->va_gid : kauth_cred_getegid(l->l_cred));
190 a++;
191
192 a->a_type = LINUX_AT_SECURE;
193 a->a_v = 0;
194 a++;
195
196 a->a_type = LINUX_AT_RANDOM;
197 a->a_v = NETBSD32PTR32I(&esdp->randbytes[0]);
198 a++;
199 esd.randbytes[0] = cprng_strong32();
200 esd.randbytes[1] = cprng_strong32();
201 esd.randbytes[2] = cprng_strong32();
202 esd.randbytes[3] = cprng_strong32();
203
204 #if 0 /* defined(__amd64__) */
205 /* XXX: broken. vsyscall must be placed in the executable page */
206 a->a_type = LINUX_AT_SYSINFO;
207 a->a_v = NETBSD32PTR32I(&esdp->kernel_vsyscall[0]);
208 a++;
209 memcpy(esd.kernel_vsyscall, linux32_kernel_vsyscall,
210 sizeof(linux32_kernel_vsyscall));
211 #endif
212
213 #if 0 /* notyet */
214 a->a_type = LINUX_AT_SYSINFO_EHDR;
215 a->a_v = NETBSD32PTR32I(&esdp->elfhdr);
216 a++;
217 memcpy(&esd.elfhdr, eh, sizeof(*eh));
218 #endif
219
220 #ifdef LINUX32_CPUCAP
221 a->a_type = LINUX_AT_HWCAP;
222 a->a_v = LINUX32_CPUCAP;
223 a++;
224 #endif
225
226 #ifdef LINUX32_PLATFORM
227 a->a_type = LINUX_AT_PLATFORM;
228 a->a_v = NETBSD32PTR32I(&esdp->hw_platform[0]);
229 a++;
230 strncpy(esd.hw_platform, LINUX32_PLATFORM, sizeof(esd.hw_platform));
231 #endif
232
233 a->a_type = AT_NULL;
234 a->a_v = 0;
235 a++;
236
237 KASSERTMSG(a <= &ai[LINUX32_ELF_AUX_ENTRIES],
238 "increase LINUX32_ELF_AUX_ENTRIES to %lu", a - ai);
239
240 /*
241 * Copy out the ELF auxiliary table and hw platform name
242 */
243 if ((error = copyout(&esd, esdp, sizeof(esd))) != 0)
244 return error;
245 *stackp += sizeof(esd);
246
247 return 0;
248 }
249