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_la48 = {
53 .sv_size = SYS_MAXSYSCALL,
54 .sv_table = sysent,
55 .sv_transtrap = NULL,
56 .sv_fixup = __elfN(freebsd_fixup),
57 .sv_sendsig = sendsig,
58 .sv_sigcode = sigcode,
59 .sv_szsigcode = &szsigcode,
60 .sv_name = "FreeBSD ELF64",
61 .sv_coredump = __elfN(coredump),
62 .sv_imgact_try = NULL,
63 .sv_minsigstksz = MINSIGSTKSZ,
64 .sv_minuser = VM_MIN_ADDRESS,
65 .sv_maxuser = VM_MAXUSER_ADDRESS_LA48,
66 .sv_usrstack = USRSTACK_LA48,
67 .sv_psstrings = PS_STRINGS_LA48,
68 .sv_stackprot = VM_PROT_ALL,
69 .sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
70 .sv_copyout_strings = exec_copyout_strings,
71 .sv_setregs = exec_setregs,
72 .sv_fixlimit = NULL,
73 .sv_maxssiz = NULL,
74 .sv_flags = SV_ABI_FREEBSD | SV_ASLR | SV_LP64 | SV_SHP |
75 SV_TIMEKEEP | SV_RNG_SEED_VER,
76 .sv_set_syscall_retval = cpu_set_syscall_retval,
77 .sv_fetch_syscall_args = cpu_fetch_syscall_args,
78 .sv_syscallnames = syscallnames,
79 .sv_shared_page_base = SHAREDPAGE_LA48,
80 .sv_shared_page_len = PAGE_SIZE,
81 .sv_schedtail = NULL,
82 .sv_thread_detach = NULL,
83 .sv_trap = NULL,
84 .sv_stackgap = elf64_stackgap,
85 };
86
87 struct sysentvec elf64_freebsd_sysvec_la57 = {
88 .sv_size = SYS_MAXSYSCALL,
89 .sv_table = sysent,
90 .sv_transtrap = NULL,
91 .sv_fixup = __elfN(freebsd_fixup),
92 .sv_sendsig = sendsig,
93 .sv_sigcode = sigcode,
94 .sv_szsigcode = &szsigcode,
95 .sv_name = "FreeBSD ELF64",
96 .sv_coredump = __elfN(coredump),
97 .sv_imgact_try = NULL,
98 .sv_minsigstksz = MINSIGSTKSZ,
99 .sv_minuser = VM_MIN_ADDRESS,
100 .sv_maxuser = VM_MAXUSER_ADDRESS_LA57,
101 .sv_usrstack = USRSTACK_LA57,
102 .sv_psstrings = PS_STRINGS_LA57,
103 .sv_stackprot = VM_PROT_ALL,
104 .sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
105 .sv_copyout_strings = exec_copyout_strings,
106 .sv_setregs = exec_setregs,
107 .sv_fixlimit = NULL,
108 .sv_maxssiz = NULL,
109 .sv_flags = SV_ABI_FREEBSD | SV_ASLR | SV_LP64 | SV_SHP |
110 SV_TIMEKEEP | SV_RNG_SEED_VER,
111 .sv_set_syscall_retval = cpu_set_syscall_retval,
112 .sv_fetch_syscall_args = cpu_fetch_syscall_args,
113 .sv_syscallnames = syscallnames,
114 .sv_shared_page_base = SHAREDPAGE_LA57,
115 .sv_shared_page_len = PAGE_SIZE,
116 .sv_schedtail = NULL,
117 .sv_thread_detach = NULL,
118 .sv_trap = NULL,
119 .sv_stackgap = elf64_stackgap,
120 };
121
122 static void
amd64_init_sysvecs(void * arg)123 amd64_init_sysvecs(void *arg)
124 {
125 amd64_lower_shared_page(&elf64_freebsd_sysvec_la48);
126 if (la57) {
127 exec_sysvec_init(&elf64_freebsd_sysvec_la57);
128 exec_sysvec_init_secondary(&elf64_freebsd_sysvec_la57,
129 &elf64_freebsd_sysvec_la48);
130 } else {
131 exec_sysvec_init(&elf64_freebsd_sysvec_la48);
132 }
133 }
134 SYSINIT(elf64_sysvec, SI_SUB_EXEC, SI_ORDER_ANY, amd64_init_sysvecs, NULL);
135
136 void
amd64_lower_shared_page(struct sysentvec * sv)137 amd64_lower_shared_page(struct sysentvec *sv)
138 {
139 if (hw_lower_amd64_sharedpage != 0) {
140 sv->sv_maxuser -= PAGE_SIZE;
141 sv->sv_shared_page_base -= PAGE_SIZE;
142 sv->sv_usrstack -= PAGE_SIZE;
143 sv->sv_psstrings -= PAGE_SIZE;
144 }
145 }
146
147 static boolean_t
freebsd_brand_info_la57_img_compat(struct image_params * imgp,int32_t * osrel __unused,uint32_t * fctl0)148 freebsd_brand_info_la57_img_compat(struct image_params *imgp,
149 int32_t *osrel __unused, uint32_t *fctl0)
150 {
151 if ((imgp->proc->p_md.md_flags & P_MD_LA57) != 0)
152 return (TRUE);
153 if (fctl0 == NULL || (*fctl0 & NT_FREEBSD_FCTL_LA48) != 0)
154 return (FALSE);
155 if ((imgp->proc->p_md.md_flags & P_MD_LA48) != 0)
156 return (FALSE);
157 return (TRUE);
158 }
159
160 static Elf64_Brandinfo freebsd_brand_info_la48 = {
161 .brand = ELFOSABI_FREEBSD,
162 .machine = EM_X86_64,
163 .compat_3_brand = "FreeBSD",
164 .emul_path = NULL,
165 .interp_path = "/libexec/ld-elf.so.1",
166 .sysvec = &elf64_freebsd_sysvec_la48,
167 .interp_newpath = NULL,
168 .brand_note = &elf64_freebsd_brandnote,
169 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE,
170 };
171
172 static Elf64_Brandinfo freebsd_brand_info_la57 = {
173 .brand = ELFOSABI_FREEBSD,
174 .machine = EM_X86_64,
175 .compat_3_brand = "FreeBSD",
176 .emul_path = NULL,
177 .interp_path = "/libexec/ld-elf.so.1",
178 .sysvec = &elf64_freebsd_sysvec_la57,
179 .interp_newpath = NULL,
180 .brand_note = &elf64_freebsd_brandnote,
181 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE,
182 .header_supported = freebsd_brand_info_la57_img_compat,
183 };
184
185 static void
sysinit_register_elf64_brand_entries(void * arg __unused)186 sysinit_register_elf64_brand_entries(void *arg __unused)
187 {
188 /*
189 * _57 must go first so it can either claim the image or hand
190 * it to _48.
191 */
192 if (la57)
193 elf64_insert_brand_entry(&freebsd_brand_info_la57);
194 elf64_insert_brand_entry(&freebsd_brand_info_la48);
195 }
196 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST,
197 sysinit_register_elf64_brand_entries, NULL);
198
199 static Elf64_Brandinfo freebsd_brand_oinfo = {
200 .brand = ELFOSABI_FREEBSD,
201 .machine = EM_X86_64,
202 .compat_3_brand = "FreeBSD",
203 .emul_path = NULL,
204 .interp_path = "/usr/libexec/ld-elf.so.1",
205 .sysvec = &elf64_freebsd_sysvec_la48,
206 .interp_newpath = NULL,
207 .brand_note = &elf64_freebsd_brandnote,
208 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
209 };
210
211 SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
212 (sysinit_cfunc_t)elf64_insert_brand_entry, &freebsd_brand_oinfo);
213
214 static Elf64_Brandinfo kfreebsd_brand_info = {
215 .brand = ELFOSABI_FREEBSD,
216 .machine = EM_X86_64,
217 .compat_3_brand = "FreeBSD",
218 .emul_path = NULL,
219 .interp_path = "/lib/ld-kfreebsd-x86-64.so.1",
220 .sysvec = &elf64_freebsd_sysvec_la48,
221 .interp_newpath = NULL,
222 .brand_note = &elf64_kfreebsd_brandnote,
223 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY
224 };
225
226 SYSINIT(kelf64, SI_SUB_EXEC, SI_ORDER_ANY,
227 (sysinit_cfunc_t)elf64_insert_brand_entry, &kfreebsd_brand_info);
228
229 void
elf64_dump_thread(struct thread * td,void * dst,size_t * off)230 elf64_dump_thread(struct thread *td, void *dst, size_t *off)
231 {
232 void *buf;
233 size_t len;
234
235 len = 0;
236 if (use_xsave) {
237 if (dst != NULL) {
238 fpugetregs(td);
239 len += elf64_populate_note(NT_X86_XSTATE,
240 get_pcb_user_save_td(td), dst,
241 cpu_max_ext_state_size, &buf);
242 *(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) =
243 xsave_mask;
244 } else
245 len += elf64_populate_note(NT_X86_XSTATE, NULL, NULL,
246 cpu_max_ext_state_size, NULL);
247 }
248 *off = len;
249 }
250
251 bool
elf_is_ifunc_reloc(Elf_Size r_info)252 elf_is_ifunc_reloc(Elf_Size r_info)
253 {
254
255 return (ELF_R_TYPE(r_info) == R_X86_64_IRELATIVE);
256 }
257
258 /* Process one elf relocation with addend. */
259 static int
elf_reloc_internal(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,bool late_ifunc,elf_lookup_fn lookup)260 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
261 int type, bool late_ifunc, elf_lookup_fn lookup)
262 {
263 Elf64_Addr *where, val;
264 Elf32_Addr *where32, val32;
265 Elf_Addr addr;
266 Elf_Addr addend;
267 Elf_Size rtype, symidx;
268 const Elf_Rel *rel;
269 const Elf_Rela *rela;
270 int error;
271
272 switch (type) {
273 case ELF_RELOC_REL:
274 rel = (const Elf_Rel *)data;
275 where = (Elf_Addr *) (relocbase + rel->r_offset);
276 rtype = ELF_R_TYPE(rel->r_info);
277 symidx = ELF_R_SYM(rel->r_info);
278 /* Addend is 32 bit on 32 bit relocs */
279 switch (rtype) {
280 case R_X86_64_PC32:
281 case R_X86_64_32S:
282 case R_X86_64_PLT32:
283 addend = *(Elf32_Addr *)where;
284 break;
285 default:
286 addend = *where;
287 break;
288 }
289 break;
290 case ELF_RELOC_RELA:
291 rela = (const Elf_Rela *)data;
292 where = (Elf_Addr *) (relocbase + rela->r_offset);
293 addend = rela->r_addend;
294 rtype = ELF_R_TYPE(rela->r_info);
295 symidx = ELF_R_SYM(rela->r_info);
296 break;
297 default:
298 panic("unknown reloc type %d\n", type);
299 }
300
301 if (late_ifunc) {
302 KASSERT(type == ELF_RELOC_RELA,
303 ("Only RELA ifunc relocations are supported"));
304 if (rtype != R_X86_64_IRELATIVE)
305 return (0);
306 }
307
308 switch (rtype) {
309 case R_X86_64_NONE: /* none */
310 break;
311
312 case R_X86_64_64: /* S + A */
313 error = lookup(lf, symidx, 1, &addr);
314 val = addr + addend;
315 if (error != 0)
316 return (-1);
317 if (*where != val)
318 *where = val;
319 break;
320
321 case R_X86_64_PC32: /* S + A - P */
322 case R_X86_64_PLT32: /* L + A - P, L is PLT location for
323 the symbol, which we treat as S */
324 error = lookup(lf, symidx, 1, &addr);
325 where32 = (Elf32_Addr *)where;
326 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
327 if (error != 0)
328 return (-1);
329 if (*where32 != val32)
330 *where32 = val32;
331 break;
332
333 case R_X86_64_32S: /* S + A sign extend */
334 error = lookup(lf, symidx, 1, &addr);
335 val32 = (Elf32_Addr)(addr + addend);
336 where32 = (Elf32_Addr *)where;
337 if (error != 0)
338 return (-1);
339 if (*where32 != val32)
340 *where32 = val32;
341 break;
342
343 case R_X86_64_COPY: /* none */
344 /*
345 * There shouldn't be copy relocations in kernel
346 * objects.
347 */
348 printf("kldload: unexpected R_COPY relocation, "
349 "symbol index %ld\n", symidx);
350 return (-1);
351
352 case R_X86_64_GLOB_DAT: /* S */
353 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */
354 error = lookup(lf, symidx, 1, &addr);
355 if (error != 0)
356 return (-1);
357 if (*where != addr)
358 *where = addr;
359 break;
360
361 case R_X86_64_RELATIVE: /* B + A */
362 addr = elf_relocaddr(lf, relocbase + addend);
363 val = addr;
364 if (*where != val)
365 *where = val;
366 break;
367
368 case R_X86_64_IRELATIVE:
369 addr = relocbase + addend;
370 val = ((Elf64_Addr (*)(void))addr)();
371 if (*where != val)
372 *where = val;
373 break;
374
375 default:
376 printf("kldload: unexpected relocation type %ld, "
377 "symbol index %ld\n", rtype, symidx);
378 return (-1);
379 }
380 return (0);
381 }
382
383 int
elf_reloc(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,elf_lookup_fn lookup)384 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
385 elf_lookup_fn lookup)
386 {
387
388 return (elf_reloc_internal(lf, relocbase, data, type, false, lookup));
389 }
390
391 int
elf_reloc_local(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,elf_lookup_fn lookup)392 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
393 int type, elf_lookup_fn lookup)
394 {
395
396 return (elf_reloc_internal(lf, relocbase, data, type, false, lookup));
397 }
398
399 int
elf_reloc_late(linker_file_t lf,Elf_Addr relocbase,const void * data,int type,elf_lookup_fn lookup)400 elf_reloc_late(linker_file_t lf, Elf_Addr relocbase, const void *data,
401 int type, elf_lookup_fn lookup)
402 {
403
404 return (elf_reloc_internal(lf, relocbase, data, type, true, lookup));
405 }
406
407 int
elf_cpu_load_file(linker_file_t lf __unused)408 elf_cpu_load_file(linker_file_t lf __unused)
409 {
410
411 return (0);
412 }
413
414 int
elf_cpu_unload_file(linker_file_t lf __unused)415 elf_cpu_unload_file(linker_file_t lf __unused)
416 {
417
418 return (0);
419 }
420
421 int
elf_cpu_parse_dynamic(caddr_t loadbase __unused,Elf_Dyn * dynamic __unused)422 elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused)
423 {
424
425 return (0);
426 }
427