1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright 1996-1998 John D. Polstra.
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include <sys/cdefs.h>
29 __FBSDID("$FreeBSD$");
30
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/exec.h>
35 #include <sys/imgact.h>
36 #include <sys/linker.h>
37 #include <sys/proc.h>
38 #include <sys/sysent.h>
39 #include <sys/imgact_elf.h>
40 #include <sys/syscall.h>
41 #include <sys/signalvar.h>
42 #include <sys/vnode.h>
43
44 #include <vm/vm.h>
45 #include <vm/pmap.h>
46 #include <vm/vm_param.h>
47
48 #include <machine/elf.h>
49 #include <machine/fpu.h>
50 #include <machine/md_var.h>
51
52 struct sysentvec elf64_freebsd_sysvec = {
53 .sv_size = SYS_MAXSYSCALL,
54 .sv_table = sysent,
55 .sv_mask = 0,
56 .sv_errsize = 0,
57 .sv_errtbl = NULL,
58 .sv_transtrap = NULL,
59 .sv_fixup = __elfN(freebsd_fixup),
60 .sv_sendsig = sendsig,
61 .sv_sigcode = sigcode,
62 .sv_szsigcode = &szsigcode,
63 .sv_name = "FreeBSD ELF64",
64 .sv_coredump = __elfN(coredump),
65 .sv_imgact_try = NULL,
66 .sv_minsigstksz = MINSIGSTKSZ,
67 .sv_minuser = VM_MIN_ADDRESS,
68 .sv_maxuser = VM_MAXUSER_ADDRESS,
69 .sv_usrstack = USRSTACK,
70 .sv_psstrings = PS_STRINGS,
71 .sv_stackprot = VM_PROT_ALL,
72 .sv_copyout_strings = exec_copyout_strings,
73 .sv_setregs = exec_setregs,
74 .sv_fixlimit = NULL,
75 .sv_maxssiz = NULL,
76 .sv_flags = SV_ABI_FREEBSD | SV_ASLR | SV_LP64 | SV_SHP |
77 SV_TIMEKEEP,
78 .sv_set_syscall_retval = cpu_set_syscall_retval,
79 .sv_fetch_syscall_args = cpu_fetch_syscall_args,
80 .sv_syscallnames = syscallnames,
81 .sv_shared_page_base = SHAREDPAGE,
82 .sv_shared_page_len = PAGE_SIZE,
83 .sv_schedtail = NULL,
84 .sv_thread_detach = NULL,
85 .sv_trap = NULL,
86 .sv_stackgap = elf64_stackgap,
87 };
88 INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec);
89
90 void
91 amd64_lower_shared_page(struct sysentvec *sv)
92 {
93 if (hw_lower_amd64_sharedpage != 0) {
94 sv->sv_maxuser -= PAGE_SIZE;
95 sv->sv_shared_page_base -= PAGE_SIZE;
96 sv->sv_usrstack -= PAGE_SIZE;
97 sv->sv_psstrings -= PAGE_SIZE;
98 }
99 }
100
101 /*
102 * Do this fixup before INIT_SYSENTVEC (SI_ORDER_ANY) because the latter
103 * uses the value of sv_shared_page_base.
104 */
105 SYSINIT(elf64_sysvec_fixup, SI_SUB_EXEC, SI_ORDER_FIRST,
106 (sysinit_cfunc_t) amd64_lower_shared_page,
107 &elf64_freebsd_sysvec);
108
109 static Elf64_Brandinfo freebsd_brand_info = {
110 .brand = ELFOSABI_FREEBSD,
111 .machine = EM_X86_64,
112 .compat_3_brand = "FreeBSD",
113 .emul_path = NULL,
114 .interp_path = "/libexec/ld-elf.so.1",
115 .sysvec = &elf64_freebsd_sysvec,
116 .interp_newpath = NULL,
117 .brand_note = &elf64_freebsd_brandnote,
118 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
119 };
120
121 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST,
122 (sysinit_cfunc_t) elf64_insert_brand_entry,
123 &freebsd_brand_info);
124
125 static Elf64_Brandinfo freebsd_brand_oinfo = {
126 .brand = ELFOSABI_FREEBSD,
127 .machine = EM_X86_64,
128 .compat_3_brand = "FreeBSD",
129 .emul_path = NULL,
130 .interp_path = "/usr/libexec/ld-elf.so.1",
131 .sysvec = &elf64_freebsd_sysvec,
132 .interp_newpath = NULL,
133 .brand_note = &elf64_freebsd_brandnote,
134 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
135 };
136
137 SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
138 (sysinit_cfunc_t) elf64_insert_brand_entry,
139 &freebsd_brand_oinfo);
140
141 static Elf64_Brandinfo kfreebsd_brand_info = {
142 .brand = ELFOSABI_FREEBSD,
143 .machine = EM_X86_64,
144 .compat_3_brand = "FreeBSD",
145 .emul_path = NULL,
146 .interp_path = "/lib/ld-kfreebsd-x86-64.so.1",
147 .sysvec = &elf64_freebsd_sysvec,
148 .interp_newpath = NULL,
149 .brand_note = &elf64_kfreebsd_brandnote,
150 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY
151 };
152
153 SYSINIT(kelf64, SI_SUB_EXEC, SI_ORDER_ANY,
154 (sysinit_cfunc_t) elf64_insert_brand_entry,
155 &kfreebsd_brand_info);
156
157 void
158 elf64_dump_thread(struct thread *td, void *dst, size_t *off)
159 {
160 void *buf;
161 size_t len;
162
163 len = 0;
164 if (use_xsave) {
165 if (dst != NULL) {
166 fpugetregs(td);
167 len += elf64_populate_note(NT_X86_XSTATE,
168 get_pcb_user_save_td(td), dst,
169 cpu_max_ext_state_size, &buf);
170 *(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) =
171 xsave_mask;
172 } else
173 len += elf64_populate_note(NT_X86_XSTATE, NULL, NULL,
174 cpu_max_ext_state_size, NULL);
175 }
176 *off = len;
177 }
178
179 bool
180 elf_is_ifunc_reloc(Elf_Size r_info)
181 {
182
183 return (ELF_R_TYPE(r_info) == R_X86_64_IRELATIVE);
184 }
185
186 /* Process one elf relocation with addend. */
187 static int
188 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
189 int type, elf_lookup_fn lookup)
190 {
191 Elf64_Addr *where, val;
192 Elf32_Addr *where32, val32;
193 Elf_Addr addr;
194 Elf_Addr addend;
195 Elf_Size rtype, symidx;
196 const Elf_Rel *rel;
197 const Elf_Rela *rela;
198 int error;
199
200 switch (type) {
201 case ELF_RELOC_REL:
202 rel = (const Elf_Rel *)data;
203 where = (Elf_Addr *) (relocbase + rel->r_offset);
204 rtype = ELF_R_TYPE(rel->r_info);
205 symidx = ELF_R_SYM(rel->r_info);
206 /* Addend is 32 bit on 32 bit relocs */
207 switch (rtype) {
208 case R_X86_64_PC32:
209 case R_X86_64_32S:
210 case R_X86_64_PLT32:
211 addend = *(Elf32_Addr *)where;
212 break;
213 default:
214 addend = *where;
215 break;
216 }
217 break;
218 case ELF_RELOC_RELA:
219 rela = (const Elf_Rela *)data;
220 where = (Elf_Addr *) (relocbase + rela->r_offset);
221 addend = rela->r_addend;
222 rtype = ELF_R_TYPE(rela->r_info);
223 symidx = ELF_R_SYM(rela->r_info);
224 break;
225 default:
226 panic("unknown reloc type %d\n", type);
227 }
228
229 switch (rtype) {
230 case R_X86_64_NONE: /* none */
231 break;
232
233 case R_X86_64_64: /* S + A */
234 error = lookup(lf, symidx, 1, &addr);
235 val = addr + addend;
236 if (error != 0)
237 return -1;
238 if (*where != val)
239 *where = val;
240 break;
241
242 case R_X86_64_PC32: /* S + A - P */
243 case R_X86_64_PLT32: /* L + A - P, L is PLT location for
244 the symbol, which we treat as S */
245 error = lookup(lf, symidx, 1, &addr);
246 where32 = (Elf32_Addr *)where;
247 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
248 if (error != 0)
249 return -1;
250 if (*where32 != val32)
251 *where32 = val32;
252 break;
253
254 case R_X86_64_32S: /* S + A sign extend */
255 error = lookup(lf, symidx, 1, &addr);
256 val32 = (Elf32_Addr)(addr + addend);
257 where32 = (Elf32_Addr *)where;
258 if (error != 0)
259 return -1;
260 if (*where32 != val32)
261 *where32 = val32;
262 break;
263
264 case R_X86_64_COPY: /* none */
265 /*
266 * There shouldn't be copy relocations in kernel
267 * objects.
268 */
269 printf("kldload: unexpected R_COPY relocation\n");
270 return (-1);
271
272 case R_X86_64_GLOB_DAT: /* S */
273 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */
274 error = lookup(lf, symidx, 1, &addr);
275 if (error != 0)
276 return -1;
277 if (*where != addr)
278 *where = addr;
279 break;
280
281 case R_X86_64_RELATIVE: /* B + A */
282 addr = elf_relocaddr(lf, relocbase + addend);
283 val = addr;
284 if (*where != val)
285 *where = val;
286 break;
287
288 case R_X86_64_IRELATIVE:
289 addr = relocbase + addend;
290 val = ((Elf64_Addr (*)(void))addr)();
291 if (*where != val)
292 *where = val;
293 break;
294
295 default:
296 printf("kldload: unexpected relocation type %ld\n",
297 rtype);
298 return (-1);
299 }
300 return (0);
301 }
302
303 int
304 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
305 elf_lookup_fn lookup)
306 {
307
308 return (elf_reloc_internal(lf, relocbase, data, type, lookup));
309 }
310
311 int
312 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
313 int type, elf_lookup_fn lookup)
314 {
315
316 return (elf_reloc_internal(lf, relocbase, data, type, lookup));
317 }
318
319 int
320 elf_cpu_load_file(linker_file_t lf __unused)
321 {
322
323 return (0);
324 }
325
326 int
327 elf_cpu_unload_file(linker_file_t lf __unused)
328 {
329
330 return (0);
331 }
Cache object: a790efebc45aa0087b7df5e807aa7bf2
|