2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
4 * Copyright (c) 1998-2000 Doug Rabson
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
35 #include <sys/param.h>
36 #include <sys/systm.h>
40 #include <sys/kernel.h>
42 #include <sys/malloc.h>
46 #include <sys/mutex.h>
47 #include <sys/mount.h>
50 #include <sys/namei.h>
51 #include <sys/fcntl.h>
52 #include <sys/vnode.h>
53 #include <sys/linker.h>
54 #include <sys/sysctl.h>
56 #include <machine/elf.h>
60 #include <security/mac/mac_framework.h>
63 #include <vm/vm_param.h>
65 #include <vm/vm_object.h>
66 #include <vm/vm_kern.h>
67 #include <vm/vm_extern.h>
70 #include <vm/vm_map.h>
72 #include <sys/link_elf.h>
74 #include "linker_if.h"
78 typedef struct elf_file {
79 struct linker_file lf; /* Common fields */
80 int preloaded; /* Was file pre-loaded */
81 caddr_t address; /* Relocation address */
83 vm_object_t object; /* VM object to hold file pages */
85 Elf_Dyn *dynamic; /* Symbol table etc. */
86 Elf_Hashelt nbuckets; /* DT_HASH info */
88 const Elf_Hashelt *buckets;
89 const Elf_Hashelt *chains;
91 caddr_t strtab; /* DT_STRTAB */
92 int strsz; /* DT_STRSZ */
93 const Elf_Sym *symtab; /* DT_SYMTAB */
94 Elf_Addr *got; /* DT_PLTGOT */
95 const Elf_Rel *pltrel; /* DT_JMPREL */
96 int pltrelsize; /* DT_PLTRELSZ */
97 const Elf_Rela *pltrela; /* DT_JMPREL */
98 int pltrelasize; /* DT_PLTRELSZ */
99 const Elf_Rel *rel; /* DT_REL */
100 int relsize; /* DT_RELSZ */
101 const Elf_Rela *rela; /* DT_RELA */
102 int relasize; /* DT_RELASZ */
104 const Elf_Sym *ddbsymtab; /* The symbol table we are using */
105 long ddbsymcnt; /* Number of symbols */
106 caddr_t ddbstrtab; /* String table */
107 long ddbstrcnt; /* number of bytes in string table */
108 caddr_t symbase; /* malloc'ed symbold base */
109 caddr_t strbase; /* malloc'ed string base */
110 caddr_t ctftab; /* CTF table */
111 long ctfcnt; /* number of bytes in CTF table */
112 caddr_t ctfoff; /* CTF offset table */
113 caddr_t typoff; /* Type offset table */
114 long typlen; /* Number of type entries. */
115 Elf_Addr pcpu_start; /* Pre-relocation pcpu set start. */
116 Elf_Addr pcpu_stop; /* Pre-relocation pcpu set stop. */
117 Elf_Addr pcpu_base; /* Relocated pcpu set address. */
119 Elf_Addr vnet_start; /* Pre-relocation vnet set start. */
120 Elf_Addr vnet_stop; /* Pre-relocation vnet set stop. */
121 Elf_Addr vnet_base; /* Relocated vnet set address. */
124 struct link_map gdb; /* hooks for gdb */
132 TAILQ_ENTRY(elf_set) es_link;
135 TAILQ_HEAD(elf_set_head, elf_set);
137 #include <kern/kern_ctf.c>
139 static int link_elf_link_common_finish(linker_file_t);
140 static int link_elf_link_preload(linker_class_t cls,
141 const char *, linker_file_t *);
142 static int link_elf_link_preload_finish(linker_file_t);
143 static int link_elf_load_file(linker_class_t, const char *,
145 static int link_elf_lookup_symbol(linker_file_t, const char *,
147 static int link_elf_symbol_values(linker_file_t, c_linker_sym_t,
149 static int link_elf_search_symbol(linker_file_t, caddr_t,
150 c_linker_sym_t *, long *);
152 static void link_elf_unload_file(linker_file_t);
153 static void link_elf_unload_preload(linker_file_t);
154 static int link_elf_lookup_set(linker_file_t, const char *,
155 void ***, void ***, int *);
156 static int link_elf_each_function_name(linker_file_t,
157 int (*)(const char *, void *), void *);
158 static int link_elf_each_function_nameval(linker_file_t,
159 linker_function_nameval_callback_t, void *);
160 static void link_elf_reloc_local(linker_file_t);
161 static long link_elf_symtab_get(linker_file_t, const Elf_Sym **);
162 static long link_elf_strtab_get(linker_file_t, caddr_t *);
163 static int elf_lookup(linker_file_t, Elf_Size, int, Elf_Addr *);
165 static kobj_method_t link_elf_methods[] = {
166 KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol),
167 KOBJMETHOD(linker_symbol_values, link_elf_symbol_values),
168 KOBJMETHOD(linker_search_symbol, link_elf_search_symbol),
169 KOBJMETHOD(linker_unload, link_elf_unload_file),
170 KOBJMETHOD(linker_load_file, link_elf_load_file),
171 KOBJMETHOD(linker_link_preload, link_elf_link_preload),
172 KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish),
173 KOBJMETHOD(linker_lookup_set, link_elf_lookup_set),
174 KOBJMETHOD(linker_each_function_name, link_elf_each_function_name),
175 KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval),
176 KOBJMETHOD(linker_ctf_get, link_elf_ctf_get),
177 KOBJMETHOD(linker_symtab_get, link_elf_symtab_get),
178 KOBJMETHOD(linker_strtab_get, link_elf_strtab_get),
182 static struct linker_class link_elf_class = {
183 #if ELF_TARG_CLASS == ELFCLASS32
188 link_elf_methods, sizeof(struct elf_file)
191 typedef int (*elf_reloc_fn)(linker_file_t lf, Elf_Addr relocbase,
192 const void *data, int type, elf_lookup_fn lookup);
194 static int parse_dynamic(elf_file_t);
195 static int relocate_file(elf_file_t);
196 static int relocate_file1(elf_file_t ef, elf_lookup_fn lookup,
197 elf_reloc_fn reloc, bool ifuncs);
198 static int link_elf_preload_parse_symbols(elf_file_t);
200 static struct elf_set_head set_pcpu_list;
202 static struct elf_set_head set_vnet_list;
206 elf_set_add(struct elf_set_head *list, Elf_Addr start, Elf_Addr stop, Elf_Addr base)
208 struct elf_set *set, *iter;
210 set = malloc(sizeof(*set), M_LINKER, M_WAITOK);
211 set->es_start = start;
215 TAILQ_FOREACH(iter, list, es_link) {
217 KASSERT((set->es_start < iter->es_start && set->es_stop < iter->es_stop) ||
218 (set->es_start > iter->es_start && set->es_stop > iter->es_stop),
219 ("linker sets intersection: to insert: 0x%jx-0x%jx; inserted: 0x%jx-0x%jx",
220 (uintmax_t)set->es_start, (uintmax_t)set->es_stop,
221 (uintmax_t)iter->es_start, (uintmax_t)iter->es_stop));
223 if (iter->es_start > set->es_start) {
224 TAILQ_INSERT_BEFORE(iter, set, es_link);
230 TAILQ_INSERT_TAIL(list, set, es_link);
234 elf_set_find(struct elf_set_head *list, Elf_Addr addr, Elf_Addr *start, Elf_Addr *base)
238 TAILQ_FOREACH(set, list, es_link) {
239 if (addr < set->es_start)
241 if (addr < set->es_stop) {
242 *start = set->es_start;
243 *base = set->es_base;
252 elf_set_delete(struct elf_set_head *list, Elf_Addr start)
256 TAILQ_FOREACH(set, list, es_link) {
257 if (start < set->es_start)
259 if (start == set->es_start) {
260 TAILQ_REMOVE(list, set, es_link);
265 KASSERT(0, ("deleting unknown linker set (start = 0x%jx)",
270 static void r_debug_state(struct r_debug *, struct link_map *);
273 * A list of loaded modules for GDB to use for loading symbols.
275 struct r_debug r_debug;
277 #define GDB_STATE(s) do { \
278 r_debug.r_state = s; r_debug_state(NULL, NULL); \
282 * Function for the debugger to set a breakpoint on to gain control.
285 r_debug_state(struct r_debug *dummy_one __unused,
286 struct link_map *dummy_two __unused)
291 link_elf_add_gdb(struct link_map *l)
293 struct link_map *prev;
297 if (r_debug.r_map == NULL) {
302 /* Append to list. */
303 for (prev = r_debug.r_map;
304 prev->l_next != NULL;
313 link_elf_delete_gdb(struct link_map *l)
315 if (l->l_prev == NULL) {
317 if ((r_debug.r_map = l->l_next) != NULL)
318 l->l_next->l_prev = NULL;
320 /* Remove any but first. */
321 if ((l->l_prev->l_next = l->l_next) != NULL)
322 l->l_next->l_prev = l->l_prev;
328 * The kernel symbol table starts here.
330 extern struct _dynamic _DYNAMIC;
333 link_elf_error(const char *filename, const char *s)
335 if (filename == NULL)
336 printf("kldload: %s\n", s);
338 printf("kldload: %s: %s\n", filename, s);
342 link_elf_invoke_ctors(caddr_t addr, size_t size)
347 if (addr == NULL || size == 0)
349 cnt = size / sizeof(*ctor);
351 for (i = 0; i < cnt; i++) {
358 * Actions performed after linking/loading both the preloaded kernel and any
359 * modules; whether preloaded or dynamicly loaded.
362 link_elf_link_common_finish(linker_file_t lf)
365 elf_file_t ef = (elf_file_t)lf;
370 /* Notify MD code that a module is being loaded. */
371 error = elf_cpu_load_file(lf);
377 ef->gdb.l_addr = lf->address;
378 newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK);
379 strcpy(newfilename, lf->filename);
380 ef->gdb.l_name = newfilename;
381 ef->gdb.l_ld = ef->dynamic;
382 link_elf_add_gdb(&ef->gdb);
383 GDB_STATE(RT_CONSISTENT);
387 link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size);
391 #ifdef RELOCATABLE_KERNEL
392 extern vm_offset_t __startkernel, __endkernel;
395 static unsigned long kern_relbase = KERNBASE;
397 SYSCTL_ULONG(_kern, OID_AUTO, base_address, CTLFLAG_RD,
398 SYSCTL_NULL_ULONG_PTR, KERNBASE, "Kernel base address");
399 SYSCTL_ULONG(_kern, OID_AUTO, relbase_address, CTLFLAG_RD,
400 &kern_relbase, 0, "Kernel relocated base address");
403 link_elf_init(void* arg)
406 Elf_Addr *ctors_addrp;
407 Elf_Size *ctors_sizep;
408 caddr_t modptr, baseptr, sizeptr;
412 linker_add_class(&link_elf_class);
414 dp = (Elf_Dyn *)&_DYNAMIC;
416 modptr = preload_search_by_type("elf" __XSTRING(__ELF_WORD_SIZE) " kernel");
418 modptr = preload_search_by_type("elf kernel");
419 modname = (char *)preload_search_info(modptr, MODINFO_NAME);
422 linker_kernel_file = linker_make_file(modname, &link_elf_class);
423 if (linker_kernel_file == NULL)
424 panic("%s: Can't create linker structures for kernel",
427 ef = (elf_file_t) linker_kernel_file;
429 #ifdef RELOCATABLE_KERNEL
430 ef->address = (caddr_t) (__startkernel - KERNBASE);
434 #ifdef SPARSE_MAPPING
441 #ifdef RELOCATABLE_KERNEL
442 linker_kernel_file->address = (caddr_t)__startkernel;
443 linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel);
444 kern_relbase = (unsigned long)__startkernel;
446 linker_kernel_file->address += KERNBASE;
447 linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
450 if (modptr != NULL) {
452 baseptr = preload_search_info(modptr, MODINFO_ADDR);
454 linker_kernel_file->address = *(caddr_t *)baseptr;
455 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
457 linker_kernel_file->size = *(size_t *)sizeptr;
458 ctors_addrp = (Elf_Addr *)preload_search_info(modptr,
459 MODINFO_METADATA | MODINFOMD_CTORS_ADDR);
460 ctors_sizep = (Elf_Size *)preload_search_info(modptr,
461 MODINFO_METADATA | MODINFOMD_CTORS_SIZE);
462 if (ctors_addrp != NULL && ctors_sizep != NULL) {
463 linker_kernel_file->ctors_addr = ef->address +
465 linker_kernel_file->ctors_size = *ctors_sizep;
468 (void)link_elf_preload_parse_symbols(ef);
471 r_debug.r_map = NULL;
472 r_debug.r_brk = r_debug_state;
473 r_debug.r_state = RT_CONSISTENT;
476 (void)link_elf_link_common_finish(linker_kernel_file);
477 linker_kernel_file->flags |= LINKER_FILE_LINKED;
478 TAILQ_INIT(&set_pcpu_list);
480 TAILQ_INIT(&set_vnet_list);
484 SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, NULL);
487 link_elf_preload_parse_symbols(elf_file_t ef)
490 caddr_t ssym, esym, base;
496 if (ef->modptr == NULL)
498 pointer = preload_search_info(ef->modptr,
499 MODINFO_METADATA | MODINFOMD_SSYM);
502 ssym = *(caddr_t *)pointer;
503 pointer = preload_search_info(ef->modptr,
504 MODINFO_METADATA | MODINFOMD_ESYM);
507 esym = *(caddr_t *)pointer;
511 symcnt = *(long *)base;
512 base += sizeof(long);
513 symtab = (Elf_Sym *)base;
514 base += roundup(symcnt, sizeof(long));
516 if (base > esym || base < ssym) {
517 printf("Symbols are corrupt!\n");
521 strcnt = *(long *)base;
522 base += sizeof(long);
524 base += roundup(strcnt, sizeof(long));
526 if (base > esym || base < ssym) {
527 printf("Symbols are corrupt!\n");
531 ef->ddbsymtab = symtab;
532 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
533 ef->ddbstrtab = strtab;
534 ef->ddbstrcnt = strcnt;
540 parse_dynamic(elf_file_t ef)
543 int plttype = DT_REL;
545 for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
549 /* From src/libexec/rtld-elf/rtld.c */
550 const Elf_Hashelt *hashtab = (const Elf_Hashelt *)
551 (ef->address + dp->d_un.d_ptr);
552 ef->nbuckets = hashtab[0];
553 ef->nchains = hashtab[1];
554 ef->buckets = hashtab + 2;
555 ef->chains = ef->buckets + ef->nbuckets;
559 ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
562 ef->strsz = dp->d_un.d_val;
565 ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
568 if (dp->d_un.d_val != sizeof(Elf_Sym))
572 ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
575 ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
578 ef->relsize = dp->d_un.d_val;
581 if (dp->d_un.d_val != sizeof(Elf_Rel))
585 ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
588 ef->pltrelsize = dp->d_un.d_val;
591 ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
594 ef->relasize = dp->d_un.d_val;
597 if (dp->d_un.d_val != sizeof(Elf_Rela))
601 plttype = dp->d_un.d_val;
602 if (plttype != DT_REL && plttype != DT_RELA)
607 dp->d_un.d_ptr = (Elf_Addr)&r_debug;
613 if (plttype == DT_RELA) {
614 ef->pltrela = (const Elf_Rela *)ef->pltrel;
616 ef->pltrelasize = ef->pltrelsize;
620 ef->ddbsymtab = ef->symtab;
621 ef->ddbsymcnt = ef->nchains;
622 ef->ddbstrtab = ef->strtab;
623 ef->ddbstrcnt = ef->strsz;
625 return elf_cpu_parse_dynamic(ef->address, ef->dynamic);
628 #define LS_PADDING 0x90909090
630 parse_dpcpu(elf_file_t ef)
633 #if defined(__i386__)
639 error = link_elf_lookup_set(&ef->lf, "pcpu", (void ***)&ef->pcpu_start,
640 (void ***)&ef->pcpu_stop, NULL);
641 /* Error just means there is no pcpu set to relocate. */
644 size = (uintptr_t)ef->pcpu_stop - (uintptr_t)ef->pcpu_start;
648 #if defined(__i386__)
649 /* In case we do find __start/stop_set_ symbols double-check. */
651 uprintf("Kernel module '%s' must be recompiled with "
652 "linker script\n", ef->lf.pathname);
656 /* Padding from linker-script correct? */
657 pad = *(uint32_t *)((uintptr_t)ef->pcpu_stop - sizeof(pad));
658 if (pad != LS_PADDING) {
659 uprintf("Kernel module '%s' must be recompiled with "
660 "linker script, invalid padding %#04x (%#04x)\n",
661 ef->lf.pathname, pad, LS_PADDING);
664 /* If we only have valid padding, nothing to do. */
669 * Allocate space in the primary pcpu area. Copy in our
670 * initialization from the data section and then initialize
671 * all per-cpu storage from that.
673 ef->pcpu_base = (Elf_Addr)(uintptr_t)dpcpu_alloc(size);
674 if (ef->pcpu_base == 0) {
675 printf("%s: pcpu module space is out of space; "
676 "cannot allocate %d for %s\n",
677 __func__, size, ef->lf.pathname);
680 memcpy((void *)ef->pcpu_base, (void *)ef->pcpu_start, size);
681 dpcpu_copy((void *)ef->pcpu_base, size);
682 elf_set_add(&set_pcpu_list, ef->pcpu_start, ef->pcpu_stop,
690 parse_vnet(elf_file_t ef)
693 #if defined(__i386__)
699 error = link_elf_lookup_set(&ef->lf, "vnet", (void ***)&ef->vnet_start,
700 (void ***)&ef->vnet_stop, NULL);
701 /* Error just means there is no vnet data set to relocate. */
704 size = (uintptr_t)ef->vnet_stop - (uintptr_t)ef->vnet_start;
708 #if defined(__i386__)
709 /* In case we do find __start/stop_set_ symbols double-check. */
711 uprintf("Kernel module '%s' must be recompiled with "
712 "linker script\n", ef->lf.pathname);
716 /* Padding from linker-script correct? */
717 pad = *(uint32_t *)((uintptr_t)ef->vnet_stop - sizeof(pad));
718 if (pad != LS_PADDING) {
719 uprintf("Kernel module '%s' must be recompiled with "
720 "linker script, invalid padding %#04x (%#04x)\n",
721 ef->lf.pathname, pad, LS_PADDING);
724 /* If we only have valid padding, nothing to do. */
729 * Allocate space in the primary vnet area. Copy in our
730 * initialization from the data section and then initialize
731 * all per-vnet storage from that.
733 ef->vnet_base = (Elf_Addr)(uintptr_t)vnet_data_alloc(size);
734 if (ef->vnet_base == 0) {
735 printf("%s: vnet module space is out of space; "
736 "cannot allocate %d for %s\n",
737 __func__, size, ef->lf.pathname);
740 memcpy((void *)ef->vnet_base, (void *)ef->vnet_start, size);
741 vnet_data_copy((void *)ef->vnet_base, size);
742 elf_set_add(&set_vnet_list, ef->vnet_start, ef->vnet_stop,
751 * Apply the specified protection to the loadable segments of a preloaded linker
755 preload_protect(elf_file_t ef, vm_prot_t prot)
759 Elf_Phdr *phdr, *phlimit;
764 hdr = (Elf_Ehdr *)ef->address;
765 phdr = (Elf_Phdr *)(ef->address + hdr->e_phoff);
766 phlimit = phdr + hdr->e_phnum;
767 for (; phdr < phlimit; phdr++) {
768 if (phdr->p_type != PT_LOAD)
771 nprot = prot | VM_PROT_READ;
772 if ((phdr->p_flags & PF_W) != 0)
773 nprot |= VM_PROT_WRITE;
774 if ((phdr->p_flags & PF_X) != 0)
775 nprot |= VM_PROT_EXECUTE;
776 error = pmap_change_prot((vm_offset_t)ef->address +
777 phdr->p_vaddr, round_page(phdr->p_memsz), nprot);
789 * Locate the ARM exception/unwind table info for DDB and stack(9) use by
790 * searching for the section header that describes it. There may be no unwind
791 * info, for example in a module containing only data.
794 link_elf_locate_exidx(linker_file_t lf, Elf_Shdr *shdr, int nhdr)
798 for (i = 0; i < nhdr; i++) {
799 if (shdr[i].sh_type == SHT_ARM_EXIDX) {
800 lf->exidx_addr = shdr[i].sh_addr + lf->address;
801 lf->exidx_size = shdr[i].sh_size;
808 * Locate the section headers metadata in a preloaded module, then use it to
809 * locate the exception/unwind table in the module. The size of the metadata
810 * block is stored in a uint32 word immediately before the data itself, and a
811 * comment in preload_search_info() says it is safe to rely on that.
814 link_elf_locate_exidx_preload(struct linker_file *lf, caddr_t modptr)
820 modinfo = (uint32_t *)preload_search_info(modptr,
821 MODINFO_METADATA | MODINFOMD_SHDR);
822 if (modinfo != NULL) {
823 shdr = (Elf_Shdr *)modinfo;
824 nhdr = modinfo[-1] / sizeof(Elf_Shdr);
825 link_elf_locate_exidx(lf, shdr, nhdr);
832 link_elf_link_preload(linker_class_t cls, const char *filename,
833 linker_file_t *result)
835 Elf_Addr *ctors_addrp;
836 Elf_Size *ctors_sizep;
837 caddr_t modptr, baseptr, sizeptr, dynptr;
844 /* Look to see if we have the file preloaded */
845 modptr = preload_search_by_name(filename);
849 type = (char *)preload_search_info(modptr, MODINFO_TYPE);
850 baseptr = preload_search_info(modptr, MODINFO_ADDR);
851 sizeptr = preload_search_info(modptr, MODINFO_SIZE);
852 dynptr = preload_search_info(modptr,
853 MODINFO_METADATA | MODINFOMD_DYNAMIC);
855 (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 &&
856 strcmp(type, "elf module") != 0))
858 if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
861 lf = linker_make_file(filename, &link_elf_class);
865 ef = (elf_file_t) lf;
868 ef->address = *(caddr_t *)baseptr;
869 #ifdef SPARSE_MAPPING
872 dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
873 ef->dynamic = (Elf_Dyn *)dp;
874 lf->address = ef->address;
875 lf->size = *(size_t *)sizeptr;
877 ctors_addrp = (Elf_Addr *)preload_search_info(modptr,
878 MODINFO_METADATA | MODINFOMD_CTORS_ADDR);
879 ctors_sizep = (Elf_Size *)preload_search_info(modptr,
880 MODINFO_METADATA | MODINFOMD_CTORS_SIZE);
881 if (ctors_addrp != NULL && ctors_sizep != NULL) {
882 lf->ctors_addr = ef->address + *ctors_addrp;
883 lf->ctors_size = *ctors_sizep;
887 link_elf_locate_exidx_preload(lf, modptr);
890 error = parse_dynamic(ef);
892 error = parse_dpcpu(ef);
895 error = parse_vnet(ef);
898 error = preload_protect(ef, VM_PROT_ALL);
900 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
903 link_elf_reloc_local(lf);
909 link_elf_link_preload_finish(linker_file_t lf)
914 ef = (elf_file_t) lf;
915 error = relocate_file(ef);
917 error = preload_protect(ef, VM_PROT_NONE);
920 (void)link_elf_preload_parse_symbols(ef);
922 return (link_elf_link_common_finish(lf));
926 link_elf_load_file(linker_class_t cls, const char* filename,
927 linker_file_t* result)
930 struct thread* td = curthread; /* XXX */
932 caddr_t firstpage, segbase;
936 Elf_Phdr *segs[MAXSEGS];
942 Elf_Addr base_vlimit;
960 NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename, td);
962 error = vn_open(&nd, &flags, 0, NULL);
965 NDFREE(&nd, NDF_ONLY_PNBUF);
966 if (nd.ni_vp->v_type != VREG) {
972 error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp);
980 * Read the elf header from the file.
982 firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK);
983 hdr = (Elf_Ehdr *)firstpage;
984 error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0,
985 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
987 nbytes = PAGE_SIZE - resid;
996 if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
997 hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
998 link_elf_error(filename, "Unsupported file layout");
1002 if (hdr->e_ident[EI_VERSION] != EV_CURRENT ||
1003 hdr->e_version != EV_CURRENT) {
1004 link_elf_error(filename, "Unsupported file version");
1008 if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
1012 if (hdr->e_machine != ELF_TARG_MACH) {
1013 link_elf_error(filename, "Unsupported machine");
1019 * We rely on the program header being in the first page.
1020 * This is not strictly required by the ABI specification, but
1021 * it seems to always true in practice. And, it simplifies
1022 * things considerably.
1024 if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
1025 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
1026 (hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
1027 link_elf_error(filename, "Unreadable program headers");
1030 * Scan the program header entries, and save key information.
1032 * We rely on there being exactly two load segments, text and data,
1035 phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
1036 phlimit = phdr + hdr->e_phnum;
1039 while (phdr < phlimit) {
1040 switch (phdr->p_type) {
1042 if (nsegs == MAXSEGS) {
1043 link_elf_error(filename, "Too many sections");
1048 * XXX: We just trust they come in right order ??
1065 if (phdyn == NULL) {
1066 link_elf_error(filename, "Object is not dynamically-linked");
1071 link_elf_error(filename, "No sections");
1077 * Allocate the entire address space of the object, to stake
1078 * out our contiguous region, and to establish the base
1079 * address for relocation.
1081 base_vaddr = trunc_page(segs[0]->p_vaddr);
1082 base_vlimit = round_page(segs[nsegs - 1]->p_vaddr +
1083 segs[nsegs - 1]->p_memsz);
1084 mapsize = base_vlimit - base_vaddr;
1086 lf = linker_make_file(filename, &link_elf_class);
1092 ef = (elf_file_t) lf;
1093 #ifdef SPARSE_MAPPING
1094 ef->object = vm_object_allocate(OBJT_PHYS, atop(mapsize));
1095 if (ef->object == NULL) {
1100 mapbase = (caddr_t)KERNBASE;
1102 mapbase = (caddr_t)vm_map_min(kernel_map);
1105 * Mapping protections are downgraded after relocation processing.
1107 error = vm_map_find(kernel_map, ef->object, 0,
1108 (vm_offset_t *)&mapbase, mapsize, 0, VMFS_OPTIMAL_SPACE,
1109 VM_PROT_ALL, VM_PROT_ALL, 0);
1111 vm_object_deallocate(ef->object);
1116 mapbase = malloc(mapsize, M_LINKER, M_EXEC | M_WAITOK);
1118 ef->address = mapbase;
1121 * Read the text and data sections and zero the bss.
1123 for (i = 0; i < nsegs; i++) {
1124 segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
1126 #ifdef SPARSE_MAPPING
1128 * Consecutive segments may have different mapping permissions,
1129 * so be strict and verify that their mappings do not overlap.
1131 if (((vm_offset_t)segbase & PAGE_MASK) != 0) {
1136 error = vm_map_wire(kernel_map,
1137 (vm_offset_t)segbase,
1138 (vm_offset_t)segbase + round_page(segs[i]->p_memsz),
1139 VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES);
1140 if (error != KERN_SUCCESS) {
1146 error = vn_rdwr(UIO_READ, nd.ni_vp,
1147 segbase, segs[i]->p_filesz, segs[i]->p_offset,
1148 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
1152 bzero(segbase + segs[i]->p_filesz,
1153 segs[i]->p_memsz - segs[i]->p_filesz);
1157 /* Update profiling information with the new text segment. */
1159 kmupetext((uintfptr_t)(mapbase + segs[0]->p_vaddr - base_vaddr +
1164 ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
1166 lf->address = ef->address;
1169 error = parse_dynamic(ef);
1172 error = parse_dpcpu(ef);
1176 error = parse_vnet(ef);
1180 link_elf_reloc_local(lf);
1182 VOP_UNLOCK(nd.ni_vp);
1183 error = linker_load_dependencies(lf);
1184 vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
1187 error = relocate_file(ef);
1191 #ifdef SPARSE_MAPPING
1193 * Downgrade permissions on text segment mappings now that relocation
1194 * processing is complete. Restrict permissions on read-only segments.
1196 for (i = 0; i < nsegs; i++) {
1199 if (segs[i]->p_type != PT_LOAD)
1202 prot = VM_PROT_READ;
1203 if ((segs[i]->p_flags & PF_W) != 0)
1204 prot |= VM_PROT_WRITE;
1205 if ((segs[i]->p_flags & PF_X) != 0)
1206 prot |= VM_PROT_EXECUTE;
1207 segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
1208 error = vm_map_protect(kernel_map,
1209 (vm_offset_t)segbase,
1210 (vm_offset_t)segbase + round_page(segs[i]->p_memsz),
1212 if (error != KERN_SUCCESS) {
1220 * Try and load the symbol table if it's present. (you can
1223 nbytes = hdr->e_shnum * hdr->e_shentsize;
1224 if (nbytes == 0 || hdr->e_shoff == 0)
1226 shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
1227 error = vn_rdwr(UIO_READ, nd.ni_vp,
1228 (caddr_t)shdr, nbytes, hdr->e_shoff,
1229 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
1234 /* Read section string table */
1235 shstrindex = hdr->e_shstrndx;
1236 if (shstrindex != 0 && shdr[shstrindex].sh_type == SHT_STRTAB &&
1237 shdr[shstrindex].sh_size != 0) {
1238 nbytes = shdr[shstrindex].sh_size;
1239 shstrs = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
1240 error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shstrs, nbytes,
1241 shdr[shstrindex].sh_offset, UIO_SYSSPACE, IO_NODELOCKED,
1242 td->td_ucred, NOCRED, &resid, td);
1249 for (i = 0; i < hdr->e_shnum; i++) {
1250 if (shdr[i].sh_type == SHT_SYMTAB) {
1252 symstrindex = shdr[i].sh_link;
1253 } else if (shstrs != NULL && shdr[i].sh_name != 0 &&
1254 strcmp(shstrs + shdr[i].sh_name, ".ctors") == 0) {
1255 /* Record relocated address and size of .ctors. */
1256 lf->ctors_addr = mapbase + shdr[i].sh_addr - base_vaddr;
1257 lf->ctors_size = shdr[i].sh_size;
1260 if (symtabindex < 0 || symstrindex < 0)
1263 symcnt = shdr[symtabindex].sh_size;
1264 ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK);
1265 strcnt = shdr[symstrindex].sh_size;
1266 ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK);
1268 error = vn_rdwr(UIO_READ, nd.ni_vp,
1269 ef->symbase, symcnt, shdr[symtabindex].sh_offset,
1270 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
1274 error = vn_rdwr(UIO_READ, nd.ni_vp,
1275 ef->strbase, strcnt, shdr[symstrindex].sh_offset,
1276 UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
1281 ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
1282 ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
1283 ef->ddbstrcnt = strcnt;
1284 ef->ddbstrtab = ef->strbase;
1289 link_elf_locate_exidx(lf, shdr, hdr->e_shnum);
1292 error = link_elf_link_common_finish(lf);
1299 VOP_UNLOCK(nd.ni_vp);
1300 vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
1301 if (error != 0 && lf != NULL)
1302 linker_file_unload(lf, LINKER_UNLOAD_FORCE);
1303 free(shdr, M_LINKER);
1304 free(firstpage, M_LINKER);
1305 free(shstrs, M_LINKER);
1311 elf_relocaddr(linker_file_t lf, Elf_Addr x)
1315 KASSERT(lf->ops->cls == (kobj_class_t)&link_elf_class,
1316 ("elf_relocaddr: unexpected linker file %p", lf));
1318 ef = (elf_file_t)lf;
1319 if (x >= ef->pcpu_start && x < ef->pcpu_stop)
1320 return ((x - ef->pcpu_start) + ef->pcpu_base);
1322 if (x >= ef->vnet_start && x < ef->vnet_stop)
1323 return ((x - ef->vnet_start) + ef->vnet_base);
1329 link_elf_unload_file(linker_file_t file)
1331 elf_file_t ef = (elf_file_t) file;
1333 if (ef->pcpu_base != 0) {
1334 dpcpu_free((void *)ef->pcpu_base,
1335 ef->pcpu_stop - ef->pcpu_start);
1336 elf_set_delete(&set_pcpu_list, ef->pcpu_start);
1339 if (ef->vnet_base != 0) {
1340 vnet_data_free((void *)ef->vnet_base,
1341 ef->vnet_stop - ef->vnet_start);
1342 elf_set_delete(&set_vnet_list, ef->vnet_start);
1346 if (ef->gdb.l_ld != NULL) {
1347 GDB_STATE(RT_DELETE);
1348 free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER);
1349 link_elf_delete_gdb(&ef->gdb);
1350 GDB_STATE(RT_CONSISTENT);
1354 /* Notify MD code that a module is being unloaded. */
1355 elf_cpu_unload_file(file);
1357 if (ef->preloaded) {
1358 link_elf_unload_preload(file);
1362 #ifdef SPARSE_MAPPING
1363 if (ef->object != NULL) {
1364 vm_map_remove(kernel_map, (vm_offset_t) ef->address,
1365 (vm_offset_t) ef->address
1366 + (ef->object->size << PAGE_SHIFT));
1369 free(ef->address, M_LINKER);
1371 free(ef->symbase, M_LINKER);
1372 free(ef->strbase, M_LINKER);
1373 free(ef->ctftab, M_LINKER);
1374 free(ef->ctfoff, M_LINKER);
1375 free(ef->typoff, M_LINKER);
1379 link_elf_unload_preload(linker_file_t file)
1382 if (file->pathname != NULL)
1383 preload_delete_name(file->pathname);
1387 symbol_name(elf_file_t ef, Elf_Size r_info)
1391 if (ELF_R_SYM(r_info)) {
1392 ref = ef->symtab + ELF_R_SYM(r_info);
1393 return (ef->strtab + ref->st_name);
1399 symbol_type(elf_file_t ef, Elf_Size r_info)
1403 if (ELF_R_SYM(r_info)) {
1404 ref = ef->symtab + ELF_R_SYM(r_info);
1405 return (ELF_ST_TYPE(ref->st_info));
1407 return (STT_NOTYPE);
1411 relocate_file1(elf_file_t ef, elf_lookup_fn lookup, elf_reloc_fn reloc,
1415 const Elf_Rela *rela;
1416 const char *symname;
1418 #define APPLY_RELOCS(iter, tbl, tblsize, type) do { \
1419 for ((iter) = (tbl); (iter) != NULL && \
1420 (iter) < (tbl) + (tblsize) / sizeof(*(iter)); (iter)++) { \
1421 if ((symbol_type(ef, (iter)->r_info) == \
1423 elf_is_ifunc_reloc((iter)->r_info)) != ifuncs) \
1425 if (reloc(&ef->lf, (Elf_Addr)ef->address, \
1426 (iter), (type), lookup)) { \
1427 symname = symbol_name(ef, (iter)->r_info); \
1428 printf("link_elf: symbol %s undefined\n", \
1435 APPLY_RELOCS(rel, ef->rel, ef->relsize, ELF_RELOC_REL);
1436 APPLY_RELOCS(rela, ef->rela, ef->relasize, ELF_RELOC_RELA);
1437 APPLY_RELOCS(rel, ef->pltrel, ef->pltrelsize, ELF_RELOC_REL);
1438 APPLY_RELOCS(rela, ef->pltrela, ef->pltrelasize, ELF_RELOC_RELA);
1446 relocate_file(elf_file_t ef)
1450 error = relocate_file1(ef, elf_lookup, elf_reloc, false);
1452 error = relocate_file1(ef, elf_lookup, elf_reloc, true);
1457 * Hash function for symbol table lookup. Don't even think about changing
1458 * this. It is specified by the System V ABI.
1460 static unsigned long
1461 elf_hash(const char *name)
1463 const unsigned char *p = (const unsigned char *) name;
1464 unsigned long h = 0;
1467 while (*p != '\0') {
1468 h = (h << 4) + *p++;
1469 if ((g = h & 0xf0000000) != 0)
1477 link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1479 elf_file_t ef = (elf_file_t) lf;
1480 unsigned long symnum;
1481 const Elf_Sym* symp;
1486 /* If we don't have a hash, bail. */
1487 if (ef->buckets == NULL || ef->nbuckets == 0) {
1488 printf("link_elf_lookup_symbol: missing symbol hash table\n");
1492 /* First, search hashed global symbols */
1493 hash = elf_hash(name);
1494 symnum = ef->buckets[hash % ef->nbuckets];
1496 while (symnum != STN_UNDEF) {
1497 if (symnum >= ef->nchains) {
1498 printf("%s: corrupt symbol table\n", __func__);
1502 symp = ef->symtab + symnum;
1503 if (symp->st_name == 0) {
1504 printf("%s: corrupt symbol table\n", __func__);
1508 strp = ef->strtab + symp->st_name;
1510 if (strcmp(name, strp) == 0) {
1511 if (symp->st_shndx != SHN_UNDEF ||
1512 (symp->st_value != 0 &&
1513 (ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
1514 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) {
1515 *sym = (c_linker_sym_t) symp;
1521 symnum = ef->chains[symnum];
1524 /* If we have not found it, look at the full table (if loaded) */
1525 if (ef->symtab == ef->ddbsymtab)
1528 /* Exhaustive search */
1529 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1530 strp = ef->ddbstrtab + symp->st_name;
1531 if (strcmp(name, strp) == 0) {
1532 if (symp->st_shndx != SHN_UNDEF ||
1533 (symp->st_value != 0 &&
1534 (ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
1535 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) {
1536 *sym = (c_linker_sym_t) symp;
1547 link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1548 linker_symval_t *symval)
1554 ef = (elf_file_t)lf;
1555 es = (const Elf_Sym *)sym;
1556 if (es >= ef->symtab && es < (ef->symtab + ef->nchains)) {
1557 symval->name = ef->strtab + es->st_name;
1558 val = (caddr_t)ef->address + es->st_value;
1559 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC)
1560 val = ((caddr_t (*)(void))val)();
1561 symval->value = val;
1562 symval->size = es->st_size;
1565 if (ef->symtab == ef->ddbsymtab)
1567 if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1568 symval->name = ef->ddbstrtab + es->st_name;
1569 val = (caddr_t)ef->address + es->st_value;
1570 if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC)
1571 val = ((caddr_t (*)(void))val)();
1572 symval->value = val;
1573 symval->size = es->st_size;
1580 link_elf_search_symbol(linker_file_t lf, caddr_t value,
1581 c_linker_sym_t *sym, long *diffp)
1583 elf_file_t ef = (elf_file_t) lf;
1584 u_long off = (uintptr_t) (void *) value;
1588 const Elf_Sym* best = NULL;
1591 for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1592 if (es->st_name == 0)
1594 st_value = es->st_value + (uintptr_t) (void *) ef->address;
1595 if (off >= st_value) {
1596 if (off - st_value < diff) {
1597 diff = off - st_value;
1601 } else if (off - st_value == diff) {
1610 *sym = (c_linker_sym_t) best;
1616 * Look up a linker set on an ELF system.
1619 link_elf_lookup_set(linker_file_t lf, const char *name,
1620 void ***startp, void ***stopp, int *countp)
1623 linker_symval_t symval;
1625 void **start, **stop;
1626 int len, error = 0, count;
1628 len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
1629 setsym = malloc(len, M_LINKER, M_WAITOK);
1631 /* get address of first entry */
1632 snprintf(setsym, len, "%s%s", "__start_set_", name);
1633 error = link_elf_lookup_symbol(lf, setsym, &sym);
1636 link_elf_symbol_values(lf, sym, &symval);
1637 if (symval.value == 0) {
1641 start = (void **)symval.value;
1643 /* get address of last entry */
1644 snprintf(setsym, len, "%s%s", "__stop_set_", name);
1645 error = link_elf_lookup_symbol(lf, setsym, &sym);
1648 link_elf_symbol_values(lf, sym, &symval);
1649 if (symval.value == 0) {
1653 stop = (void **)symval.value;
1655 /* and the number of entries */
1656 count = stop - start;
1667 free(setsym, M_LINKER);
1672 link_elf_each_function_name(linker_file_t file,
1673 int (*callback)(const char *, void *), void *opaque)
1675 elf_file_t ef = (elf_file_t)file;
1676 const Elf_Sym *symp;
1679 /* Exhaustive search */
1680 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1681 if (symp->st_value != 0 &&
1682 (ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
1683 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) {
1684 error = callback(ef->ddbstrtab + symp->st_name, opaque);
1693 link_elf_each_function_nameval(linker_file_t file,
1694 linker_function_nameval_callback_t callback, void *opaque)
1696 linker_symval_t symval;
1697 elf_file_t ef = (elf_file_t)file;
1698 const Elf_Sym* symp;
1701 /* Exhaustive search */
1702 for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1703 if (symp->st_value != 0 &&
1704 (ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
1705 ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) {
1706 error = link_elf_symbol_values(file,
1707 (c_linker_sym_t) symp, &symval);
1710 error = callback(file, i, &symval, opaque);
1719 elf_get_sym(linker_file_t lf, Elf_Size symidx)
1721 elf_file_t ef = (elf_file_t)lf;
1723 if (symidx >= ef->nchains)
1725 return (ef->symtab + symidx);
1729 elf_get_symname(linker_file_t lf, Elf_Size symidx)
1731 elf_file_t ef = (elf_file_t)lf;
1734 if (symidx >= ef->nchains)
1736 sym = ef->symtab + symidx;
1737 return (ef->strtab + sym->st_name);
1741 * Symbol lookup function that can be used when the symbol index is known (ie
1742 * in relocations). It uses the symbol index instead of doing a fully fledged
1743 * hash table based lookup when such is valid. For example for local symbols.
1744 * This is not only more efficient, it's also more correct. It's not always
1745 * the case that the symbol can be found through the hash table.
1748 elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res)
1750 elf_file_t ef = (elf_file_t)lf;
1753 Elf_Addr addr, start, base;
1755 /* Don't even try to lookup the symbol if the index is bogus. */
1756 if (symidx >= ef->nchains) {
1761 sym = ef->symtab + symidx;
1764 * Don't do a full lookup when the symbol is local. It may even
1765 * fail because it may not be found through the hash table.
1767 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
1768 /* Force lookup failure when we have an insanity. */
1769 if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0) {
1773 *res = ((Elf_Addr)ef->address + sym->st_value);
1778 * XXX we can avoid doing a hash table based lookup for global
1779 * symbols as well. This however is not always valid, so we'll
1780 * just do it the hard way for now. Performance tweaks can
1784 symbol = ef->strtab + sym->st_name;
1786 /* Force a lookup failure if the symbol name is bogus. */
1792 addr = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
1793 if (addr == 0 && ELF_ST_BIND(sym->st_info) != STB_WEAK) {
1798 if (elf_set_find(&set_pcpu_list, addr, &start, &base))
1799 addr = addr - start + base;
1801 else if (elf_set_find(&set_vnet_list, addr, &start, &base))
1802 addr = addr - start + base;
1809 link_elf_reloc_local(linker_file_t lf)
1811 const Elf_Rel *rellim;
1813 const Elf_Rela *relalim;
1814 const Elf_Rela *rela;
1815 elf_file_t ef = (elf_file_t)lf;
1817 /* Perform relocations without addend if there are any: */
1818 if ((rel = ef->rel) != NULL) {
1819 rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
1820 while (rel < rellim) {
1821 elf_reloc_local(lf, (Elf_Addr)ef->address, rel,
1822 ELF_RELOC_REL, elf_lookup);
1827 /* Perform relocations with addend if there are any: */
1828 if ((rela = ef->rela) != NULL) {
1829 relalim = (const Elf_Rela *)
1830 ((const char *)ef->rela + ef->relasize);
1831 while (rela < relalim) {
1832 elf_reloc_local(lf, (Elf_Addr)ef->address, rela,
1833 ELF_RELOC_RELA, elf_lookup);
1840 link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
1842 elf_file_t ef = (elf_file_t)lf;
1844 *symtab = ef->ddbsymtab;
1846 if (*symtab == NULL)
1849 return (ef->ddbsymcnt);
1853 link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
1855 elf_file_t ef = (elf_file_t)lf;
1857 *strtab = ef->ddbstrtab;
1859 if (*strtab == NULL)
1862 return (ef->ddbstrcnt);
1865 #if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) || defined(__powerpc__)
1867 * Use this lookup routine when performing relocations early during boot.
1868 * The generic lookup routine depends on kobj, which is not initialized
1872 elf_lookup_ifunc(linker_file_t lf, Elf_Size symidx, int deps __unused,
1876 const Elf_Sym *symp;
1879 ef = (elf_file_t)lf;
1880 symp = ef->symtab + symidx;
1881 if (ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC) {
1882 val = (caddr_t)ef->address + symp->st_value;
1883 *res = ((Elf_Addr (*)(void))val)();
1890 link_elf_ireloc(caddr_t kmdp)
1892 struct elf_file eff;
1897 bzero_early(ef, sizeof(*ef));
1900 ef->dynamic = (Elf_Dyn *)&_DYNAMIC;
1902 #ifdef RELOCATABLE_KERNEL
1903 ef->address = (caddr_t) (__startkernel - KERNBASE);
1909 link_elf_preload_parse_symbols(ef);
1910 relocate_file1(ef, elf_lookup_ifunc, elf_reloc, true);