1 /*-
2 * Copyright 1996-1998 John D. Polstra.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
24 */
25
26 #include <sys/cdefs.h>
27 __FBSDID("$FreeBSD: releng/11.2/sys/amd64/amd64/elf_machdep.c 333720 2018-05-17 15:24:53Z kib $");
28
29 #include <sys/param.h>
30 #include <sys/kernel.h>
31 #include <sys/systm.h>
32 #include <sys/exec.h>
33 #include <sys/imgact.h>
34 #include <sys/linker.h>
35 #include <sys/proc.h>
36 #include <sys/sysent.h>
37 #include <sys/imgact_elf.h>
38 #include <sys/syscall.h>
39 #include <sys/signalvar.h>
40 #include <sys/vnode.h>
41
42 #include <vm/vm.h>
43 #include <vm/pmap.h>
44 #include <vm/vm_param.h>
45
46 #include <machine/elf.h>
47 #include <machine/fpu.h>
48 #include <machine/md_var.h>
49
50 struct sysentvec elf64_freebsd_sysvec = {
51 .sv_size = SYS_MAXSYSCALL,
52 .sv_table = sysent,
53 .sv_mask = 0,
54 .sv_errsize = 0,
55 .sv_errtbl = NULL,
56 .sv_transtrap = NULL,
57 .sv_fixup = __elfN(freebsd_fixup),
58 .sv_sendsig = sendsig,
59 .sv_sigcode = sigcode,
60 .sv_szsigcode = &szsigcode,
61 .sv_name = "FreeBSD ELF64",
62 .sv_coredump = __elfN(coredump),
63 .sv_imgact_try = NULL,
64 .sv_minsigstksz = MINSIGSTKSZ,
65 .sv_pagesize = PAGE_SIZE,
66 .sv_minuser = VM_MIN_ADDRESS,
67 .sv_maxuser = VM_MAXUSER_ADDRESS,
68 .sv_usrstack = USRSTACK,
69 .sv_psstrings = PS_STRINGS,
70 .sv_stackprot = VM_PROT_ALL,
71 .sv_copyout_strings = exec_copyout_strings,
72 .sv_setregs = exec_setregs,
73 .sv_fixlimit = NULL,
74 .sv_maxssiz = NULL,
75 .sv_flags = SV_ABI_FREEBSD | SV_LP64 | SV_SHP | SV_TIMEKEEP,
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,
80 .sv_shared_page_len = PAGE_SIZE,
81 .sv_schedtail = NULL,
82 .sv_thread_detach = NULL,
83 .sv_trap = NULL,
84 };
85 INIT_SYSENTVEC(elf64_sysvec, &elf64_freebsd_sysvec);
86
87 void
88 amd64_lower_shared_page(struct sysentvec *sv)
89 {
90 if (hw_lower_amd64_sharedpage != 0) {
91 sv->sv_maxuser -= PAGE_SIZE;
92 sv->sv_shared_page_base -= PAGE_SIZE;
93 sv->sv_usrstack -= PAGE_SIZE;
94 sv->sv_psstrings -= PAGE_SIZE;
95 }
96 }
97
98 /*
99 * Do this fixup before INIT_SYSENTVEC (SI_ORDER_ANY) because the latter
100 * uses the value of sv_shared_page_base.
101 */
102 SYSINIT(elf64_sysvec_fixup, SI_SUB_EXEC, SI_ORDER_FIRST,
103 (sysinit_cfunc_t) amd64_lower_shared_page,
104 &elf64_freebsd_sysvec);
105
106 static Elf64_Brandinfo freebsd_brand_info = {
107 .brand = ELFOSABI_FREEBSD,
108 .machine = EM_X86_64,
109 .compat_3_brand = "FreeBSD",
110 .emul_path = NULL,
111 .interp_path = "/libexec/ld-elf.so.1",
112 .sysvec = &elf64_freebsd_sysvec,
113 .interp_newpath = NULL,
114 .brand_note = &elf64_freebsd_brandnote,
115 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
116 };
117
118 SYSINIT(elf64, SI_SUB_EXEC, SI_ORDER_FIRST,
119 (sysinit_cfunc_t) elf64_insert_brand_entry,
120 &freebsd_brand_info);
121
122 static Elf64_Brandinfo freebsd_brand_oinfo = {
123 .brand = ELFOSABI_FREEBSD,
124 .machine = EM_X86_64,
125 .compat_3_brand = "FreeBSD",
126 .emul_path = NULL,
127 .interp_path = "/usr/libexec/ld-elf.so.1",
128 .sysvec = &elf64_freebsd_sysvec,
129 .interp_newpath = NULL,
130 .brand_note = &elf64_freebsd_brandnote,
131 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE
132 };
133
134 SYSINIT(oelf64, SI_SUB_EXEC, SI_ORDER_ANY,
135 (sysinit_cfunc_t) elf64_insert_brand_entry,
136 &freebsd_brand_oinfo);
137
138 static Elf64_Brandinfo kfreebsd_brand_info = {
139 .brand = ELFOSABI_FREEBSD,
140 .machine = EM_X86_64,
141 .compat_3_brand = "FreeBSD",
142 .emul_path = NULL,
143 .interp_path = "/lib/ld-kfreebsd-x86-64.so.1",
144 .sysvec = &elf64_freebsd_sysvec,
145 .interp_newpath = NULL,
146 .brand_note = &elf64_kfreebsd_brandnote,
147 .flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE_MANDATORY
148 };
149
150 SYSINIT(kelf64, SI_SUB_EXEC, SI_ORDER_ANY,
151 (sysinit_cfunc_t) elf64_insert_brand_entry,
152 &kfreebsd_brand_info);
153
154 void
155 elf64_dump_thread(struct thread *td, void *dst, size_t *off)
156 {
157 void *buf;
158 size_t len;
159
160 len = 0;
161 if (use_xsave) {
162 if (dst != NULL) {
163 fpugetregs(td);
164 len += elf64_populate_note(NT_X86_XSTATE,
165 get_pcb_user_save_td(td), dst,
166 cpu_max_ext_state_size, &buf);
167 *(uint64_t *)((char *)buf + X86_XSTATE_XCR0_OFFSET) =
168 xsave_mask;
169 } else
170 len += elf64_populate_note(NT_X86_XSTATE, NULL, NULL,
171 cpu_max_ext_state_size, NULL);
172 }
173 *off = len;
174 }
175
176 #define ERI_LOCAL 0x0001
177 #define ERI_ONLYIFUNC 0x0002
178
179 /* Process one elf relocation with addend. */
180 static int
181 elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
182 int type, elf_lookup_fn lookup, int flags)
183 {
184 Elf64_Addr *where, val;
185 Elf32_Addr *where32, val32;
186 Elf_Addr addr;
187 Elf_Addr addend;
188 Elf_Size rtype, symidx;
189 const Elf_Rel *rel;
190 const Elf_Rela *rela;
191 int error;
192
193 switch (type) {
194 case ELF_RELOC_REL:
195 rel = (const Elf_Rel *)data;
196 where = (Elf_Addr *) (relocbase + rel->r_offset);
197 rtype = ELF_R_TYPE(rel->r_info);
198 symidx = ELF_R_SYM(rel->r_info);
199 /* Addend is 32 bit on 32 bit relocs */
200 switch (rtype) {
201 case R_X86_64_PC32:
202 case R_X86_64_32S:
203 addend = *(Elf32_Addr *)where;
204 break;
205 default:
206 addend = *where;
207 break;
208 }
209 break;
210 case ELF_RELOC_RELA:
211 rela = (const Elf_Rela *)data;
212 where = (Elf_Addr *) (relocbase + rela->r_offset);
213 addend = rela->r_addend;
214 rtype = ELF_R_TYPE(rela->r_info);
215 symidx = ELF_R_SYM(rela->r_info);
216 break;
217 default:
218 panic("unknown reloc type %d\n", type);
219 }
220
221 if (((flags & ERI_ONLYIFUNC) == 0) ^ (rtype != R_X86_64_IRELATIVE))
222 return (0);
223
224 switch (rtype) {
225 case R_X86_64_NONE: /* none */
226 break;
227
228 case R_X86_64_64: /* S + A */
229 error = lookup(lf, symidx, 1, &addr);
230 val = addr + addend;
231 if (error != 0)
232 return -1;
233 if (*where != val)
234 *where = val;
235 break;
236
237 case R_X86_64_PC32: /* S + A - P */
238 error = lookup(lf, symidx, 1, &addr);
239 where32 = (Elf32_Addr *)where;
240 val32 = (Elf32_Addr)(addr + addend - (Elf_Addr)where);
241 if (error != 0)
242 return -1;
243 if (*where32 != val32)
244 *where32 = val32;
245 break;
246
247 case R_X86_64_32S: /* S + A sign extend */
248 error = lookup(lf, symidx, 1, &addr);
249 val32 = (Elf32_Addr)(addr + addend);
250 where32 = (Elf32_Addr *)where;
251 if (error != 0)
252 return -1;
253 if (*where32 != val32)
254 *where32 = val32;
255 break;
256
257 case R_X86_64_COPY: /* none */
258 /*
259 * There shouldn't be copy relocations in kernel
260 * objects.
261 */
262 printf("kldload: unexpected R_COPY relocation\n");
263 return (-1);
264 break;
265
266 case R_X86_64_GLOB_DAT: /* S */
267 case R_X86_64_JMP_SLOT: /* XXX need addend + offset */
268 error = lookup(lf, symidx, 1, &addr);
269 if (error != 0)
270 return -1;
271 if (*where != addr)
272 *where = addr;
273 break;
274
275 case R_X86_64_RELATIVE: /* B + A */
276 addr = relocbase + addend;
277 val = addr;
278 if (*where != val)
279 *where = val;
280 break;
281
282 case R_X86_64_IRELATIVE:
283 addr = relocbase + addend;
284 val = ((Elf64_Addr (*)(void))addr)();
285 if (*where != val)
286 *where = val;
287 break;
288
289 default:
290 printf("kldload: unexpected relocation type %ld\n",
291 rtype);
292 return (-1);
293 }
294 return (0);
295 }
296
297 int
298 elf_reloc_ifunc(linker_file_t lf, Elf_Addr relocbase, const void *data,
299 int type, elf_lookup_fn lookup)
300 {
301
302 return (elf_reloc_internal(lf, relocbase, data, type, lookup,
303 ERI_ONLYIFUNC));
304 }
305
306 int
307 elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
308 elf_lookup_fn lookup)
309 {
310
311 return (elf_reloc_internal(lf, relocbase, data, type, lookup, 0));
312 }
313
314 int
315 elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
316 int type, elf_lookup_fn lookup)
317 {
318
319 return (elf_reloc_internal(lf, relocbase, data, type, lookup,
320 ERI_LOCAL));
321 }
322
323 int
324 elf_cpu_load_file(linker_file_t lf __unused)
325 {
326
327 return (0);
328 }
329
330 int
331 elf_cpu_unload_file(linker_file_t lf __unused)
332 {
333
334 return (0);
335 }
Cache object: 8cb6766f45366704ca7bd2a921bc0f0a
|