kernel - lwkt_token revamp
[dragonfly.git] / sys / kern / link_elf_obj.c
1 /*-
2  * Copyright (c) 1998 Doug Rabson
3  * Copyright (c) 2004 Peter Wemm
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD: src/sys/kern/link_elf.c,v 1.24 1999/12/24 15:33:36 bde Exp $
28  * $DragonFly: src/sys/kern/link_elf.c,v 1.29 2008/08/01 23:11:16 dillon Exp $
29  */
30
31 #include <sys/param.h>
32 #include <sys/kernel.h>
33 #include <sys/systm.h>
34 #include <sys/malloc.h>
35 #include <sys/proc.h>
36 #include <sys/nlookup.h>
37 #include <sys/fcntl.h>
38 #include <sys/vnode.h>
39 #include <sys/linker.h>
40 #include <machine/elf.h>
41
42 #include <vm/vm.h>
43 #include <vm/vm_param.h>
44 #include <vm/vm_zone.h>
45 #include <vm/vm_object.h>
46 #include <vm/vm_kern.h>
47 #include <vm/vm_extern.h>
48 #include <sys/lock.h>
49 #include <vm/pmap.h>
50 #include <vm/vm_map.h>
51
52 static int      link_elf_obj_preload_file(const char *, linker_file_t *);
53 static int      link_elf_obj_preload_finish(linker_file_t);
54 static int      link_elf_obj_load_file(const char *, linker_file_t *);
55 static int
56 link_elf_obj_lookup_symbol(linker_file_t, const char *,
57                        c_linker_sym_t *);
58 static int      link_elf_obj_symbol_values(linker_file_t, c_linker_sym_t, linker_symval_t *);
59 static int
60 link_elf_obj_search_symbol(linker_file_t, caddr_t value,
61                        c_linker_sym_t * sym, long *diffp);
62
63 static void     link_elf_obj_unload_file(linker_file_t);
64 static int
65 link_elf_obj_lookup_set(linker_file_t, const char *,
66                     void ***, void ***, int *);
67 static void     link_elf_obj_reloc_local(linker_file_t lf);
68 static int elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *);
69
70 static struct linker_class_ops link_elf_obj_class_ops = {
71         link_elf_obj_load_file,
72         link_elf_obj_preload_file,
73 };
74
75 static struct linker_file_ops link_elf_obj_file_ops = {
76         .lookup_symbol = link_elf_obj_lookup_symbol,
77         .symbol_values = link_elf_obj_symbol_values,
78         .search_symbol = link_elf_obj_search_symbol,
79         .preload_finish = link_elf_obj_preload_finish,
80         .unload = link_elf_obj_unload_file,
81         .lookup_set = link_elf_obj_lookup_set,
82 };
83
84 typedef struct {
85         void           *addr;
86         Elf_Off         size;
87         int             flags;
88         int             sec;            /* Original section */
89         char           *name;
90 }               Elf_progent;
91
92 typedef struct {
93         Elf_Rel        *rel;
94         int             nrel;
95         int             sec;
96 }               Elf_relent;
97
98 typedef struct {
99         Elf_Rela       *rela;
100         int             nrela;
101         int             sec;
102 }               Elf_relaent;
103
104
105 typedef struct elf_file {
106         int             preloaded;
107
108         caddr_t         address;        /* Relocation address */
109         vm_object_t     object;         /* VM object to hold file pages */
110         Elf_Shdr       *e_shdr;
111
112         Elf_progent    *progtab;
113         int             nprogtab;
114
115         Elf_relaent    *relatab;
116         int             nrelatab;
117
118         Elf_relent     *reltab;
119         int             nreltab;
120
121         Elf_Sym        *ddbsymtab;      /* The symbol table we are using */
122         long            ddbsymcnt;      /* Number of symbols */
123         caddr_t         ddbstrtab;      /* String table */
124         long            ddbstrcnt;      /* number of bytes in string table */
125
126         caddr_t         shstrtab;       /* Section name string table */
127         long            shstrcnt;       /* number of bytes in string table */
128
129         caddr_t         ctftab;         /* CTF table */
130         long            ctfcnt;         /* number of bytes in CTF table */
131         caddr_t         ctfoff;         /* CTF offset table */
132         caddr_t         typoff;         /* Type offset table */
133         long            typlen;         /* Number of type entries. */
134
135 }              *elf_file_t;
136
137 static int      relocate_file(linker_file_t lf);
138
139 /*
140  * The kernel symbol table starts here.
141  */
142 extern struct _dynamic _DYNAMIC;
143
144 static void
145 link_elf_obj_init(void *arg)
146 {
147 #if ELF_TARG_CLASS == ELFCLASS32
148         linker_add_class("elf32", NULL, &link_elf_obj_class_ops);
149 #else
150         linker_add_class("elf64", NULL, &link_elf_obj_class_ops);
151 #endif
152 }
153
154 SYSINIT(link_elf, SI_BOOT2_KLD, SI_ORDER_SECOND, link_elf_obj_init, 0);
155
156 static void
157 link_elf_obj_error(const char *file, const char *s)
158 {
159         kprintf("kldload: %s: %s\n", file, s);
160 }
161
162 static int
163 link_elf_obj_preload_file(const char *filename, linker_file_t *result)
164 {
165         Elf_Ehdr       *hdr;
166         Elf_Shdr       *shdr;
167         Elf_Sym *es;
168         caddr_t         modptr, baseptr, sizeptr;
169         char           *type;
170         elf_file_t      ef;
171         linker_file_t   lf;
172         Elf_Addr        off;
173         int             error, i, j, pb, ra, rl, shstrindex, symstrindex, symtabindex;
174
175         /*
176          * Look to see if we have the module preloaded.
177          */
178         modptr = preload_search_by_name(filename);
179         if (modptr == NULL)
180                 return ENOENT;
181
182         /* It's preloaded, check we can handle it and collect information */
183         type = (char *)preload_search_info(modptr, MODINFO_TYPE);
184         baseptr = preload_search_info(modptr, MODINFO_ADDR);
185         sizeptr = preload_search_info(modptr, MODINFO_SIZE);
186         hdr = (Elf_Ehdr *) preload_search_info(modptr, MODINFO_METADATA |
187                                                MODINFOMD_ELFHDR);
188         shdr = (Elf_Shdr *) preload_search_info(modptr, MODINFO_METADATA |
189                                                 MODINFOMD_SHDR);
190         if (type == NULL ||
191             (strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " obj module") != 0 &&
192              strcmp(type, "elf obj module") != 0)) {
193                 return (EFTYPE);
194         }
195         if (baseptr == NULL || sizeptr == NULL || hdr == NULL || shdr == NULL)
196                 return (EINVAL);
197
198         ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
199         ef->preloaded = 1;
200         ef->address = *(caddr_t *) baseptr;
201         lf = linker_make_file(filename, ef, &link_elf_obj_file_ops);
202         if (lf == NULL) {
203                 kfree(ef, M_LINKER);
204                 return ENOMEM;
205         }
206         lf->address = ef->address;
207         lf->size = *(size_t *) sizeptr;
208
209         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
210             hdr->e_ident[EI_DATA] != ELF_TARG_DATA ||
211             hdr->e_ident[EI_VERSION] != EV_CURRENT ||
212             hdr->e_version != EV_CURRENT ||
213             hdr->e_type != ET_REL ||
214             hdr->e_machine != ELF_TARG_MACH) {
215                 error = EFTYPE;
216                 goto out;
217         }
218         ef->e_shdr = shdr;
219
220         /* Scan the section header for information and table sizing. */
221         symtabindex = -1;
222         symstrindex = -1;
223         for (i = 0; i < hdr->e_shnum; i++) {
224                 switch (shdr[i].sh_type) {
225                 case SHT_PROGBITS:
226                 case SHT_NOBITS:
227                         ef->nprogtab++;
228                         break;
229                 case SHT_SYMTAB:
230                         symtabindex = i;
231                         symstrindex = shdr[i].sh_link;
232                         break;
233                 case SHT_REL:
234                         ef->nreltab++;
235                         break;
236                 case SHT_RELA:
237                         ef->nrelatab++;
238                         break;
239                 }
240         }
241
242         shstrindex = hdr->e_shstrndx;
243         if (ef->nprogtab == 0 || symstrindex < 0 ||
244             symstrindex >= hdr->e_shnum ||
245             shdr[symstrindex].sh_type != SHT_STRTAB || shstrindex == 0 ||
246             shstrindex >= hdr->e_shnum ||
247             shdr[shstrindex].sh_type != SHT_STRTAB) {
248                 error = ENOEXEC;
249                 goto out;
250         }
251         /* Allocate space for tracking the load chunks */
252         if (ef->nprogtab != 0)
253                 ef->progtab = kmalloc(ef->nprogtab * sizeof(*ef->progtab),
254                                      M_LINKER, M_WAITOK | M_ZERO);
255         if (ef->nreltab != 0)
256                 ef->reltab = kmalloc(ef->nreltab * sizeof(*ef->reltab),
257                                     M_LINKER, M_WAITOK | M_ZERO);
258         if (ef->nrelatab != 0)
259                 ef->relatab = kmalloc(ef->nrelatab * sizeof(*ef->relatab),
260                                      M_LINKER, M_WAITOK | M_ZERO);
261         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
262             (ef->nreltab != 0 && ef->reltab == NULL) ||
263             (ef->nrelatab != 0 && ef->relatab == NULL)) {
264                 error = ENOMEM;
265                 goto out;
266         }
267         /* XXX, relocate the sh_addr fields saved by the loader. */
268         off = 0;
269         for (i = 0; i < hdr->e_shnum; i++) {
270                 if (shdr[i].sh_addr != 0 && (off == 0 || shdr[i].sh_addr < off))
271                         off = shdr[i].sh_addr;
272         }
273         for (i = 0; i < hdr->e_shnum; i++) {
274                 if (shdr[i].sh_addr != 0)
275                         shdr[i].sh_addr = shdr[i].sh_addr - off +
276                                 (Elf_Addr) ef->address;
277         }
278
279         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
280         ef->ddbsymtab = (Elf_Sym *) shdr[symtabindex].sh_addr;
281         ef->ddbstrcnt = shdr[symstrindex].sh_size;
282         ef->ddbstrtab = (char *)shdr[symstrindex].sh_addr;
283         ef->shstrcnt = shdr[shstrindex].sh_size;
284         ef->shstrtab = (char *)shdr[shstrindex].sh_addr;
285
286         /* Now fill out progtab and the relocation tables. */
287         pb = 0;
288         rl = 0;
289         ra = 0;
290         for (i = 0; i < hdr->e_shnum; i++) {
291                 switch (shdr[i].sh_type) {
292                 case SHT_PROGBITS:
293                 case SHT_NOBITS:
294                         ef->progtab[pb].addr = (void *)shdr[i].sh_addr;
295                         if (shdr[i].sh_type == SHT_PROGBITS)
296                                 ef->progtab[pb].name = "<<PROGBITS>>";
297                         else
298                                 ef->progtab[pb].name = "<<NOBITS>>";
299                         ef->progtab[pb].size = shdr[i].sh_size;
300                         ef->progtab[pb].sec = i;
301                         if (ef->shstrtab && shdr[i].sh_name != 0)
302                                 ef->progtab[pb].name =
303                                         ef->shstrtab + shdr[i].sh_name;
304 #if 0
305                         if (ef->progtab[pb].name != NULL &&
306                             !strcmp(ef->progtab[pb].name, "set_pcpu")) {
307                                 void           *dpcpu;
308
309                                 dpcpu = dpcpu_alloc(shdr[i].sh_size);
310                                 if (dpcpu == NULL) {
311                                         error = ENOSPC;
312                                         goto out;
313                                 }
314                                 memcpy(dpcpu, ef->progtab[pb].addr,
315                                        ef->progtab[pb].size);
316                                 dpcpu_copy(dpcpu, shdr[i].sh_size);
317                                 ef->progtab[pb].addr = dpcpu;
318 #ifdef VIMAGE
319                         } else if (ef->progtab[pb].name != NULL &&
320                                    !strcmp(ef->progtab[pb].name, VNET_SETNAME)) {
321                                 void           *vnet_data;
322
323                                 vnet_data = vnet_data_alloc(shdr[i].sh_size);
324                                 if (vnet_data == NULL) {
325                                         error = ENOSPC;
326                                         goto out;
327                                 }
328                                 memcpy(vnet_data, ef->progtab[pb].addr,
329                                        ef->progtab[pb].size);
330                                 vnet_data_copy(vnet_data, shdr[i].sh_size);
331                                 ef->progtab[pb].addr = vnet_data;
332 #endif
333                         }
334 #endif
335                         /* Update all symbol values with the offset. */
336                         for (j = 0; j < ef->ddbsymcnt; j++) {
337                                 es = &ef->ddbsymtab[j];
338                                 if (es->st_shndx != i)
339                                         continue;
340                                 es->st_value += (Elf_Addr) ef->progtab[pb].addr;
341                         }
342                         pb++;
343                         break;
344                 case SHT_REL:
345                         ef->reltab[rl].rel = (Elf_Rel *) shdr[i].sh_addr;
346                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
347                         ef->reltab[rl].sec = shdr[i].sh_info;
348                         rl++;
349                         break;
350                 case SHT_RELA:
351                         ef->relatab[ra].rela = (Elf_Rela *) shdr[i].sh_addr;
352                         ef->relatab[ra].nrela =
353                                 shdr[i].sh_size / sizeof(Elf_Rela);
354                         ef->relatab[ra].sec = shdr[i].sh_info;
355                         ra++;
356                         break;
357                 }
358         }
359         if (pb != ef->nprogtab)
360                 panic("lost progbits");
361         if (rl != ef->nreltab)
362                 panic("lost reltab");
363         if (ra != ef->nrelatab)
364                 panic("lost relatab");
365
366         /* Local intra-module relocations */
367         link_elf_obj_reloc_local(lf);
368
369         *result = lf;
370         return (0);
371
372 out:
373         /* preload not done this way */
374         linker_file_unload(lf /* , LINKER_UNLOAD_FORCE */ );
375         return (error);
376 }
377
378 static int
379 link_elf_obj_preload_finish(linker_file_t lf)
380 {
381         int error;
382
383         error = relocate_file(lf);
384
385         return (error);
386 }
387
388 static int
389 link_elf_obj_load_file(const char *filename, linker_file_t * result)
390 {
391         struct nlookupdata nd;
392         struct thread  *td = curthread; /* XXX */
393         struct proc    *p = td->td_proc;
394         char           *pathname;
395         struct vnode   *vp;
396         Elf_Ehdr       *hdr;
397         Elf_Shdr       *shdr;
398         Elf_Sym        *es;
399         int             nbytes, i, j;
400         vm_offset_t     mapbase;
401         size_t          mapsize;
402         int             error = 0;
403         int             resid;
404         elf_file_t      ef;
405         linker_file_t   lf;
406         int             symtabindex;
407         int             symstrindex;
408         int             shstrindex;
409         int             nsym;
410         int             pb, rl, ra;
411         int             alignmask;
412
413         KKASSERT(p != NULL);
414         if (p->p_ucred == NULL) {
415                 kprintf("link_elf_obj_load_file: cannot load '%s' from filesystem"
416                         " this early\n", filename);
417                 return ENOENT;
418         }
419         shdr = NULL;
420         lf = NULL;
421         mapsize = 0;
422         hdr = NULL;
423         pathname = linker_search_path(filename);
424         if (pathname == NULL)
425                 return ENOENT;
426
427         error = nlookup_init(&nd, pathname, UIO_SYSSPACE, NLC_FOLLOW | NLC_LOCKVP);
428         if (error == 0)
429                 error = vn_open(&nd, NULL, FREAD, 0);
430         kfree(pathname, M_LINKER);
431         if (error) {
432                 nlookup_done(&nd);
433                 return error;
434         }
435         vp = nd.nl_open_vp;
436         nd.nl_open_vp = NULL;
437         nlookup_done(&nd);
438
439         /*
440          * Read the elf header from the file.
441          */
442         hdr = kmalloc(sizeof(*hdr), M_LINKER, M_WAITOK);
443         if (hdr == NULL) {
444                 error = ENOMEM;
445                 goto out;
446         }
447         error = vn_rdwr(UIO_READ, vp, (void *)hdr, sizeof(*hdr), 0,
448                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
449         if (error)
450                 goto out;
451         if (resid != 0) {
452                 error = ENOEXEC;
453                 goto out;
454         }
455         if (!IS_ELF(*hdr)) {
456                 error = ENOEXEC;
457                 goto out;
458         }
459
460         if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS
461             || hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
462                 link_elf_obj_error(filename, "Unsupported file layout");
463                 error = ENOEXEC;
464                 goto out;
465         }
466         if (hdr->e_ident[EI_VERSION] != EV_CURRENT
467             || hdr->e_version != EV_CURRENT) {
468                 link_elf_obj_error(filename, "Unsupported file version");
469                 error = ENOEXEC;
470                 goto out;
471         }
472         if (hdr->e_type != ET_REL) {
473                 error = ENOSYS;
474                 goto out;
475         }
476         if (hdr->e_machine != ELF_TARG_MACH) {
477                 link_elf_obj_error(filename, "Unsupported machine");
478                 error = ENOEXEC;
479                 goto out;
480         }
481
482         ef = kmalloc(sizeof(struct elf_file), M_LINKER, M_WAITOK | M_ZERO);
483         lf = linker_make_file(filename, ef, &link_elf_obj_file_ops);
484         if (lf == NULL) {
485                 kfree(ef, M_LINKER);
486                 error = ENOMEM;
487                 goto out;
488         }
489         ef->nprogtab = 0;
490         ef->e_shdr = 0;
491         ef->nreltab = 0;
492         ef->nrelatab = 0;
493
494         /* Allocate and read in the section header */
495         nbytes = hdr->e_shnum * hdr->e_shentsize;
496         if (nbytes == 0 || hdr->e_shoff == 0 ||
497             hdr->e_shentsize != sizeof(Elf_Shdr)) {
498                 error = ENOEXEC;
499                 goto out;
500         }
501         shdr = kmalloc(nbytes, M_LINKER, M_WAITOK);
502         if (shdr == NULL) {
503                 error = ENOMEM;
504                 goto out;
505         }
506         ef->e_shdr = shdr;
507         error = vn_rdwr(UIO_READ, vp, (caddr_t) shdr, nbytes, hdr->e_shoff,
508                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
509         if (error)
510                 goto out;
511         if (resid) {
512                 error = ENOEXEC;
513                 goto out;
514         }
515         /* Scan the section header for information and table sizing. */
516         nsym = 0;
517         symtabindex = -1;
518         symstrindex = -1;
519         for (i = 0; i < hdr->e_shnum; i++) {
520                 switch (shdr[i].sh_type) {
521                 case SHT_PROGBITS:
522                 case SHT_NOBITS:
523                         ef->nprogtab++;
524                         break;
525                 case SHT_SYMTAB:
526                         nsym++;
527                         symtabindex = i;
528                         symstrindex = shdr[i].sh_link;
529                         break;
530                 case SHT_REL:
531                         ef->nreltab++;
532                         break;
533                 case SHT_RELA:
534                         ef->nrelatab++;
535                         break;
536                 case SHT_STRTAB:
537                         break;
538                 }
539         }
540         if (ef->nprogtab == 0) {
541                 link_elf_obj_error(filename, "file has no contents");
542                 error = ENOEXEC;
543                 goto out;
544         }
545         if (nsym != 1) {
546                 /* Only allow one symbol table for now */
547                 link_elf_obj_error(filename, "file has no valid symbol table");
548                 error = ENOEXEC;
549                 goto out;
550         }
551         if (symstrindex < 0 || symstrindex > hdr->e_shnum ||
552             shdr[symstrindex].sh_type != SHT_STRTAB) {
553                 link_elf_obj_error(filename, "file has invalid symbol strings");
554                 error = ENOEXEC;
555                 goto out;
556         }
557         /* Allocate space for tracking the load chunks */
558         if (ef->nprogtab != 0)
559                 ef->progtab = kmalloc(ef->nprogtab * sizeof(*ef->progtab),
560                                       M_LINKER, M_WAITOK | M_ZERO);
561         if (ef->nreltab != 0)
562                 ef->reltab = kmalloc(ef->nreltab * sizeof(*ef->reltab),
563                                      M_LINKER, M_WAITOK | M_ZERO);
564         if (ef->nrelatab != 0)
565                 ef->relatab = kmalloc(ef->nrelatab * sizeof(*ef->relatab),
566                                       M_LINKER, M_WAITOK | M_ZERO);
567         if ((ef->nprogtab != 0 && ef->progtab == NULL) ||
568             (ef->nreltab != 0 && ef->reltab == NULL) ||
569             (ef->nrelatab != 0 && ef->relatab == NULL)) {
570                 error = ENOMEM;
571                 goto out;
572         }
573         if (symtabindex == -1)
574                 panic("lost symbol table index");
575         /* Allocate space for and load the symbol table */
576         ef->ddbsymcnt = shdr[symtabindex].sh_size / sizeof(Elf_Sym);
577         ef->ddbsymtab = kmalloc(shdr[symtabindex].sh_size, M_LINKER, M_WAITOK);
578         if (ef->ddbsymtab == NULL) {
579                 error = ENOMEM;
580                 goto out;
581         }
582         error = vn_rdwr(UIO_READ, vp, (void *)ef->ddbsymtab,
583                         shdr[symtabindex].sh_size, shdr[symtabindex].sh_offset,
584                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
585         if (error)
586                 goto out;
587         if (resid != 0) {
588                 error = EINVAL;
589                 goto out;
590         }
591         if (symstrindex == -1)
592                 panic("lost symbol string index");
593         /* Allocate space for and load the symbol strings */
594         ef->ddbstrcnt = shdr[symstrindex].sh_size;
595         ef->ddbstrtab = kmalloc(shdr[symstrindex].sh_size, M_LINKER, M_WAITOK);
596         if (ef->ddbstrtab == NULL) {
597                 error = ENOMEM;
598                 goto out;
599         }
600         error = vn_rdwr(UIO_READ, vp, ef->ddbstrtab,
601                         shdr[symstrindex].sh_size, shdr[symstrindex].sh_offset,
602                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
603         if (error)
604                 goto out;
605         if (resid != 0) {
606                 error = EINVAL;
607                 goto out;
608         }
609         /* Do we have a string table for the section names?  */
610         shstrindex = -1;
611         if (hdr->e_shstrndx != 0 &&
612             shdr[hdr->e_shstrndx].sh_type == SHT_STRTAB) {
613                 shstrindex = hdr->e_shstrndx;
614                 ef->shstrcnt = shdr[shstrindex].sh_size;
615                 ef->shstrtab = kmalloc(shdr[shstrindex].sh_size, M_LINKER,
616                                        M_WAITOK);
617                 if (ef->shstrtab == NULL) {
618                         error = ENOMEM;
619                         goto out;
620                 }
621                 error = vn_rdwr(UIO_READ, vp, ef->shstrtab,
622                                 shdr[shstrindex].sh_size, shdr[shstrindex].sh_offset,
623                                 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
624                 if (error)
625                         goto out;
626                 if (resid != 0) {
627                         error = EINVAL;
628                         goto out;
629                 }
630         }
631         /* Size up code/data(progbits) and bss(nobits). */
632         alignmask = 0;
633         for (i = 0; i < hdr->e_shnum; i++) {
634                 switch (shdr[i].sh_type) {
635                 case SHT_PROGBITS:
636                 case SHT_NOBITS:
637                         alignmask = shdr[i].sh_addralign - 1;
638                         mapsize += alignmask;
639                         mapsize &= ~alignmask;
640                         mapsize += shdr[i].sh_size;
641                         break;
642                 }
643         }
644
645         /*
646          * We know how much space we need for the text/data/bss/etc. This
647          * stuff needs to be in a single chunk so that profiling etc can get
648          * the bounds and gdb can associate offsets with modules
649          */
650         ef->object = vm_object_allocate(OBJT_DEFAULT,
651                                         round_page(mapsize) >> PAGE_SHIFT);
652         if (ef->object == NULL) {
653                 error = ENOMEM;
654                 goto out;
655         }
656         ef->address = (caddr_t) vm_map_min(&kernel_map);
657
658         /*
659          * In order to satisfy x86_64's architectural requirements on the
660          * location of code and data in the kernel's address space, request a
661          * mapping that is above the kernel.
662          */
663         mapbase = KERNBASE;
664         error = vm_map_find(&kernel_map, ef->object, 0, &mapbase,
665                             round_page(mapsize), PAGE_SIZE,
666                             TRUE, VM_MAPTYPE_NORMAL,
667                             VM_PROT_ALL, VM_PROT_ALL, FALSE);
668         if (error) {
669                 vm_object_deallocate(ef->object);
670                 ef->object = 0;
671                 goto out;
672         }
673         /* Wire the pages */
674         error = vm_map_wire(&kernel_map, mapbase,
675                             mapbase + round_page(mapsize), 0);
676         if (error != KERN_SUCCESS) {
677                 error = ENOMEM;
678                 goto out;
679         }
680         /* Inform the kld system about the situation */
681         lf->address = ef->address = (caddr_t) mapbase;
682         lf->size = mapsize;
683
684         /*
685          * Now load code/data(progbits), zero bss(nobits), allocate space for
686          * and load relocs
687          */
688         pb = 0;
689         rl = 0;
690         ra = 0;
691         alignmask = 0;
692         for (i = 0; i < hdr->e_shnum; i++) {
693                 switch (shdr[i].sh_type) {
694                 case SHT_PROGBITS:
695                 case SHT_NOBITS:
696                         alignmask = shdr[i].sh_addralign - 1;
697                         mapbase += alignmask;
698                         mapbase &= ~alignmask;
699                         if (ef->shstrtab && shdr[i].sh_name != 0)
700                                 ef->progtab[pb].name =
701                                         ef->shstrtab + shdr[i].sh_name;
702                         else if (shdr[i].sh_type == SHT_PROGBITS)
703                                 ef->progtab[pb].name = "<<PROGBITS>>";
704                         else
705                                 ef->progtab[pb].name = "<<NOBITS>>";
706 #if 0
707                         if (ef->progtab[pb].name != NULL &&
708                             !strcmp(ef->progtab[pb].name, "set_pcpu"))
709                                 ef->progtab[pb].addr =
710                                         dpcpu_alloc(shdr[i].sh_size);
711 #ifdef VIMAGE
712                         else if (ef->progtab[pb].name != NULL &&
713                                  !strcmp(ef->progtab[pb].name, VNET_SETNAME))
714                                 ef->progtab[pb].addr =
715                                         vnet_data_alloc(shdr[i].sh_size);
716 #endif
717                         else
718 #endif
719                                 ef->progtab[pb].addr =
720                                         (void *)(uintptr_t) mapbase;
721                         if (ef->progtab[pb].addr == NULL) {
722                                 error = ENOSPC;
723                                 goto out;
724                         }
725                         ef->progtab[pb].size = shdr[i].sh_size;
726                         ef->progtab[pb].sec = i;
727                         if (shdr[i].sh_type == SHT_PROGBITS) {
728                                 error = vn_rdwr(UIO_READ, vp,
729                                                 ef->progtab[pb].addr,
730                                                 shdr[i].sh_size, shdr[i].sh_offset,
731                                                 UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred,
732                                                 &resid);
733                                 if (error)
734                                         goto out;
735                                 if (resid != 0) {
736                                         error = EINVAL;
737                                         goto out;
738                                 }
739 #if 0
740                                 /* Initialize the per-cpu or vnet area. */
741                                 if (ef->progtab[pb].addr != (void *)mapbase &&
742                                     !strcmp(ef->progtab[pb].name, "set_pcpu"))
743                                         dpcpu_copy(ef->progtab[pb].addr,
744                                                    shdr[i].sh_size);
745 #ifdef VIMAGE
746                                 else if (ef->progtab[pb].addr !=
747                                          (void *)mapbase &&
748                                          !strcmp(ef->progtab[pb].name, VNET_SETNAME))
749                                         vnet_data_copy(ef->progtab[pb].addr,
750                                                        shdr[i].sh_size);
751 #endif
752 #endif
753                         } else
754                                 bzero(ef->progtab[pb].addr, shdr[i].sh_size);
755
756                         /* Update all symbol values with the offset. */
757                         for (j = 0; j < ef->ddbsymcnt; j++) {
758                                 es = &ef->ddbsymtab[j];
759                                 if (es->st_shndx != i)
760                                         continue;
761                                 es->st_value += (Elf_Addr) ef->progtab[pb].addr;
762                         }
763                         mapbase += shdr[i].sh_size;
764                         pb++;
765                         break;
766                 case SHT_REL:
767                         ef->reltab[rl].rel = kmalloc(shdr[i].sh_size, M_LINKER, M_WAITOK);
768                         ef->reltab[rl].nrel = shdr[i].sh_size / sizeof(Elf_Rel);
769                         ef->reltab[rl].sec = shdr[i].sh_info;
770                         error = vn_rdwr(UIO_READ, vp,
771                                         (void *)ef->reltab[rl].rel,
772                                         shdr[i].sh_size, shdr[i].sh_offset,
773                                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
774                         if (error)
775                                 goto out;
776                         if (resid != 0) {
777                                 error = EINVAL;
778                                 goto out;
779                         }
780                         rl++;
781                         break;
782                 case SHT_RELA:
783                         ef->relatab[ra].rela = kmalloc(shdr[i].sh_size, M_LINKER, M_WAITOK);
784                         ef->relatab[ra].nrela = shdr[i].sh_size / sizeof(Elf_Rela);
785                         ef->relatab[ra].sec = shdr[i].sh_info;
786                         error = vn_rdwr(UIO_READ, vp,
787                                         (void *)ef->relatab[ra].rela,
788                                         shdr[i].sh_size, shdr[i].sh_offset,
789                                         UIO_SYSSPACE, IO_NODELOCKED, p->p_ucred, &resid);
790                         if (error)
791                                 goto out;
792                         if (resid != 0) {
793                                 error = EINVAL;
794                                 goto out;
795                         }
796                         ra++;
797                         break;
798                 }
799         }
800         if (pb != ef->nprogtab)
801                 panic("lost progbits");
802         if (rl != ef->nreltab)
803                 panic("lost reltab");
804         if (ra != ef->nrelatab)
805                 panic("lost relatab");
806         if (mapbase != (vm_offset_t) ef->address + mapsize)
807                 panic("mapbase 0x%lx != address %p + mapsize 0x%lx (0x%lx)\n",
808                       mapbase, ef->address, mapsize,
809                       (vm_offset_t) ef->address + mapsize);
810
811         /* Local intra-module relocations */
812         link_elf_obj_reloc_local(lf);
813
814         /* Pull in dependencies */
815         error = linker_load_dependencies(lf);
816         if (error)
817                 goto out;
818
819         /* External relocations */
820         error = relocate_file(lf);
821         if (error)
822                 goto out;
823
824         *result = lf;
825
826 out:
827         if (error && lf)
828                 linker_file_unload(lf /*, LINKER_UNLOAD_FORCE */);
829         if (hdr)
830                 kfree(hdr, M_LINKER);
831         vn_unlock(vp);
832         vn_close(vp, FREAD);
833
834         return error;
835 }
836
837 static void
838 link_elf_obj_unload_file(linker_file_t file)
839 {
840         elf_file_t      ef = file->priv;
841         int i;
842
843         if (ef->progtab) {
844                 for (i = 0; i < ef->nprogtab; i++) {
845                         if (ef->progtab[i].size == 0)
846                                 continue;
847                         if (ef->progtab[i].name == NULL)
848                                 continue;
849 #if 0
850                         if (!strcmp(ef->progtab[i].name, "set_pcpu"))
851                                 dpcpu_free(ef->progtab[i].addr,
852                                     ef->progtab[i].size);
853 #ifdef VIMAGE
854                         else if (!strcmp(ef->progtab[i].name, VNET_SETNAME))
855                                 vnet_data_free(ef->progtab[i].addr,
856                                     ef->progtab[i].size);
857 #endif
858 #endif
859                 }
860         }
861         if (ef->preloaded) {
862                 if (ef->reltab)
863                         kfree(ef->reltab, M_LINKER);
864                 if (ef->relatab)
865                         kfree(ef->relatab, M_LINKER);
866                 if (ef->progtab)
867                         kfree(ef->progtab, M_LINKER);
868                 if (ef->ctftab)
869                         kfree(ef->ctftab, M_LINKER);
870                 if (ef->ctfoff)
871                         kfree(ef->ctfoff, M_LINKER);
872                 if (ef->typoff)
873                         kfree(ef->typoff, M_LINKER);
874                 if (file->filename != NULL)
875                         preload_delete_name(file->filename);
876                 kfree(ef, M_LINKER);
877                 /* XXX reclaim module memory? */
878                 return;
879         }
880
881         for (i = 0; i < ef->nreltab; i++)
882                 if (ef->reltab[i].rel)
883                         kfree(ef->reltab[i].rel, M_LINKER);
884         for (i = 0; i < ef->nrelatab; i++)
885                 if (ef->relatab[i].rela)
886                         kfree(ef->relatab[i].rela, M_LINKER);
887         if (ef->reltab)
888                 kfree(ef->reltab, M_LINKER);
889         if (ef->relatab)
890                 kfree(ef->relatab, M_LINKER);
891         if (ef->progtab)
892                 kfree(ef->progtab, M_LINKER);
893
894         if (ef->object) {
895                 vm_map_remove(&kernel_map, (vm_offset_t) ef->address,
896                     (vm_offset_t) ef->address +
897                     (ef->object->size << PAGE_SHIFT));
898         }
899         if (ef->e_shdr)
900                 kfree(ef->e_shdr, M_LINKER);
901         if (ef->ddbsymtab)
902                 kfree(ef->ddbsymtab, M_LINKER);
903         if (ef->ddbstrtab)
904                 kfree(ef->ddbstrtab, M_LINKER);
905         if (ef->shstrtab)
906                 kfree(ef->shstrtab, M_LINKER);
907         if (ef->ctftab)
908                 kfree(ef->ctftab, M_LINKER);
909         if (ef->ctfoff)
910                 kfree(ef->ctfoff, M_LINKER);
911         if (ef->typoff)
912                 kfree(ef->typoff, M_LINKER);
913         kfree(ef, M_LINKER);
914 }
915
916 static const char *
917 symbol_name(elf_file_t ef, Elf_Size r_info)
918 {
919         const Elf_Sym  *ref;
920
921         if (ELF_R_SYM(r_info)) {
922                 ref = ef->ddbsymtab + ELF_R_SYM(r_info);
923                 return ef->ddbstrtab + ref->st_name;
924         } else
925                 return NULL;
926 }
927
928 static Elf_Addr
929 findbase(elf_file_t ef, int sec)
930 {
931         int i;
932         Elf_Addr base = 0;
933
934         for (i = 0; i < ef->nprogtab; i++) {
935                 if (sec == ef->progtab[i].sec) {
936                         base = (Elf_Addr)ef->progtab[i].addr;
937                         break;
938                 }
939         }
940         return base;
941 }
942
943 static int
944 relocate_file(linker_file_t lf)
945 {
946         elf_file_t      ef = lf->priv;
947         const Elf_Rel *rellim;
948         const Elf_Rel *rel;
949         const Elf_Rela *relalim;
950         const Elf_Rela *rela;
951         const char *symname;
952         const Elf_Sym *sym;
953         int i;
954         Elf_Size symidx;
955         Elf_Addr base;
956
957         /* Perform relocations without addend if there are any: */
958         for (i = 0; i < ef->nreltab; i++) {
959                 rel = ef->reltab[i].rel;
960                 if (rel == NULL)
961                         panic("lost a reltab!");
962                 rellim = rel + ef->reltab[i].nrel;
963                 base = findbase(ef, ef->reltab[i].sec);
964                 if (base == 0)
965                         panic("lost base for reltab");
966                 for ( ; rel < rellim; rel++) {
967                         symidx = ELF_R_SYM(rel->r_info);
968                         if (symidx >= ef->ddbsymcnt)
969                                 continue;
970                         sym = ef->ddbsymtab + symidx;
971                         /* Local relocs are already done */
972                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
973                                 continue;
974                         if (elf_reloc(lf, base, rel, ELF_RELOC_REL,
975                             elf_obj_lookup)) {
976                                 symname = symbol_name(ef, rel->r_info);
977                                 kprintf("link_elf_obj_obj: symbol %s undefined\n",
978                                     symname);
979                                 return ENOENT;
980                         }
981                 }
982         }
983
984         /* Perform relocations with addend if there are any: */
985         for (i = 0; i < ef->nrelatab; i++) {
986                 rela = ef->relatab[i].rela;
987                 if (rela == NULL)
988                         panic("lost a relatab!");
989                 relalim = rela + ef->relatab[i].nrela;
990                 base = findbase(ef, ef->relatab[i].sec);
991                 if (base == 0)
992                         panic("lost base for relatab");
993                 for ( ; rela < relalim; rela++) {
994                         symidx = ELF_R_SYM(rela->r_info);
995                         if (symidx >= ef->ddbsymcnt)
996                                 continue;
997                         sym = ef->ddbsymtab + symidx;
998                         /* Local relocs are already done */
999                         if (ELF_ST_BIND(sym->st_info) == STB_LOCAL)
1000                                 continue;
1001                         if (elf_reloc(lf, base, rela, ELF_RELOC_RELA,
1002                             elf_obj_lookup)) {
1003                                 symname = symbol_name(ef, rela->r_info);
1004                                 kprintf("link_elf_obj_obj: symbol %s undefined\n",
1005                                     symname);
1006                                 return ENOENT;
1007                         }
1008                 }
1009         }
1010
1011         return 0;
1012 }
1013
1014 static int
1015 link_elf_obj_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
1016 {
1017         elf_file_t ef = lf->priv;
1018         const Elf_Sym *symp;
1019         const char *strp;
1020         int i;
1021
1022         for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
1023                 strp = ef->ddbstrtab + symp->st_name;
1024                 if (symp->st_shndx != SHN_UNDEF && strcmp(name, strp) == 0) {
1025                         *sym = (c_linker_sym_t) symp;
1026                         return 0;
1027                 }
1028         }
1029         return ENOENT;
1030 }
1031
1032 static int
1033 link_elf_obj_symbol_values(linker_file_t lf, c_linker_sym_t sym,
1034     linker_symval_t *symval)
1035 {
1036         elf_file_t ef = lf->priv;
1037         const Elf_Sym *es = (const Elf_Sym*) sym;
1038
1039         if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
1040                 symval->name = ef->ddbstrtab + es->st_name;
1041                 symval->value = (caddr_t)es->st_value;
1042                 symval->size = es->st_size;
1043                 return 0;
1044         }
1045         return ENOENT;
1046 }
1047
1048 static int
1049 link_elf_obj_search_symbol(linker_file_t lf, caddr_t value,
1050     c_linker_sym_t *sym, long *diffp)
1051 {
1052         elf_file_t ef = lf->priv;
1053         u_long off = (uintptr_t) (void *) value;
1054         u_long diff = off;
1055         u_long st_value;
1056         const Elf_Sym *es;
1057         const Elf_Sym *best = 0;
1058         int i;
1059
1060         for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
1061                 if (es->st_name == 0)
1062                         continue;
1063                 st_value = es->st_value;
1064                 if (off >= st_value) {
1065                         if (off - st_value < diff) {
1066                                 diff = off - st_value;
1067                                 best = es;
1068                                 if (diff == 0)
1069                                         break;
1070                         } else if (off - st_value == diff) {
1071                                 best = es;
1072                         }
1073                 }
1074         }
1075         if (best == 0)
1076                 *diffp = off;
1077         else
1078                 *diffp = diff;
1079         *sym = (c_linker_sym_t) best;
1080
1081         return 0;
1082 }
1083
1084 /*
1085  * Look up a linker set on an ELF system.
1086  */
1087 static int
1088 link_elf_obj_lookup_set(linker_file_t lf, const char *name,
1089     void ***startp, void ***stopp, int *countp)
1090 {
1091         elf_file_t ef = lf->priv;
1092         void **start, **stop;
1093         int i, count;
1094
1095         /* Relative to section number */
1096         for (i = 0; i < ef->nprogtab; i++) {
1097                 if ((strncmp(ef->progtab[i].name, "set_", 4) == 0) &&
1098                     strcmp(ef->progtab[i].name + 4, name) == 0) {
1099                         start  = (void **)ef->progtab[i].addr;
1100                         stop = (void **)((char *)ef->progtab[i].addr +
1101                             ef->progtab[i].size);
1102                         count = stop - start;
1103                         if (startp)
1104                                 *startp = start;
1105                         if (stopp)
1106                                 *stopp = stop;
1107                         if (countp)
1108                                 *countp = count;
1109                         return (0);
1110                 }
1111         }
1112         return (ESRCH);
1113 }
1114
1115 /*
1116  * Symbol lookup function that can be used when the symbol index is known (ie
1117  * in relocations). It uses the symbol index instead of doing a fully fledged
1118  * hash table based lookup when such is valid. For example for local symbols.
1119  * This is not only more efficient, it's also more correct. It's not always
1120  * the case that the symbol can be found through the hash table.
1121  */
1122 static int
1123 elf_obj_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *result)
1124 {
1125         elf_file_t ef = lf->priv;
1126         const Elf_Sym *sym;
1127         const char *symbol;
1128
1129         /* Don't even try to lookup the symbol if the index is bogus. */
1130         if (symidx >= ef->ddbsymcnt)
1131                 return (ENOENT);
1132
1133         sym = ef->ddbsymtab + symidx;
1134
1135         /* Quick answer if there is a definition included. */
1136         if (sym->st_shndx != SHN_UNDEF) {
1137                 *result = sym->st_value;
1138                 return (0);
1139         }
1140
1141         /* If we get here, then it is undefined and needs a lookup. */
1142         switch (ELF_ST_BIND(sym->st_info)) {
1143         case STB_LOCAL:
1144                 /* Local, but undefined? huh? */
1145                 return (ENOENT);
1146
1147         case STB_GLOBAL:
1148                 /* Relative to Data or Function name */
1149                 symbol = ef->ddbstrtab + sym->st_name;
1150
1151                 /* Force a lookup failure if the symbol name is bogus. */
1152                 if (*symbol == 0)
1153                         return (ENOENT);
1154                 return (linker_file_lookup_symbol(lf, symbol, deps, (caddr_t *)result));
1155
1156         case STB_WEAK:
1157                 kprintf("link_elf_obj_obj: Weak symbols not supported\n");
1158                 return (ENOENT);
1159
1160         default:
1161                 return (ENOENT);
1162         }
1163 }
1164
1165 static void
1166 link_elf_obj_fix_link_set(elf_file_t ef)
1167 {
1168         static const char startn[] = "__start_";
1169         static const char stopn[] = "__stop_";
1170         Elf_Sym *sym;
1171         const char *sym_name, *linkset_name;
1172         Elf_Addr startp, stopp;
1173         Elf_Size symidx;
1174         int start, i;
1175
1176         startp = stopp = 0;
1177         for (symidx = 1 /* zero entry is special */;
1178                 symidx < ef->ddbsymcnt; symidx++) {
1179                 sym = ef->ddbsymtab + symidx;
1180                 if (sym->st_shndx != SHN_UNDEF)
1181                         continue;
1182
1183                 sym_name = ef->ddbstrtab + sym->st_name;
1184                 if (strncmp(sym_name, startn, sizeof(startn) - 1) == 0) {
1185                         start = 1;
1186                         linkset_name = sym_name + sizeof(startn) - 1;
1187                 }
1188                 else if (strncmp(sym_name, stopn, sizeof(stopn) - 1) == 0) {
1189                         start = 0;
1190                         linkset_name = sym_name + sizeof(stopn) - 1;
1191                 }
1192                 else
1193                         continue;
1194
1195                 for (i = 0; i < ef->nprogtab; i++) {
1196                         if (strcmp(ef->progtab[i].name, linkset_name) == 0) {
1197                                 startp = (Elf_Addr)ef->progtab[i].addr;
1198                                 stopp = (Elf_Addr)(startp + ef->progtab[i].size);
1199                                 break;
1200                         }
1201                 }
1202                 if (i == ef->nprogtab)
1203                         continue;
1204
1205                 sym->st_value = start ? startp : stopp;
1206                 sym->st_shndx = i;
1207         }
1208 }
1209
1210 static void
1211 link_elf_obj_reloc_local(linker_file_t lf)
1212 {
1213         elf_file_t ef = lf->priv;
1214         const Elf_Rel *rellim;
1215         const Elf_Rel *rel;
1216         const Elf_Rela *relalim;
1217         const Elf_Rela *rela;
1218         const Elf_Sym *sym;
1219         Elf_Addr base;
1220         int i;
1221         Elf_Size symidx;
1222
1223         link_elf_obj_fix_link_set(ef);
1224
1225         /* Perform relocations without addend if there are any: */
1226         for (i = 0; i < ef->nreltab; i++) {
1227                 rel = ef->reltab[i].rel;
1228                 if (rel == NULL)
1229                         panic("lost a reltab!");
1230                 rellim = rel + ef->reltab[i].nrel;
1231                 base = findbase(ef, ef->reltab[i].sec);
1232                 if (base == 0)
1233                         panic("lost base for reltab");
1234                 for ( ; rel < rellim; rel++) {
1235                         symidx = ELF_R_SYM(rel->r_info);
1236                         if (symidx >= ef->ddbsymcnt)
1237                                 continue;
1238                         sym = ef->ddbsymtab + symidx;
1239                         /* Only do local relocs */
1240                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1241                                 continue;
1242                         elf_reloc_local(lf, base, rel, ELF_RELOC_REL,
1243                             elf_obj_lookup);
1244                 }
1245         }
1246
1247         /* Perform relocations with addend if there are any: */
1248         for (i = 0; i < ef->nrelatab; i++) {
1249                 rela = ef->relatab[i].rela;
1250                 if (rela == NULL)
1251                         panic("lost a relatab!");
1252                 relalim = rela + ef->relatab[i].nrela;
1253                 base = findbase(ef, ef->relatab[i].sec);
1254                 if (base == 0)
1255                         panic("lost base for relatab");
1256                 for ( ; rela < relalim; rela++) {
1257                         symidx = ELF_R_SYM(rela->r_info);
1258                         if (symidx >= ef->ddbsymcnt)
1259                                 continue;
1260                         sym = ef->ddbsymtab + symidx;
1261                         /* Only do local relocs */
1262                         if (ELF_ST_BIND(sym->st_info) != STB_LOCAL)
1263                                 continue;
1264                         elf_reloc_local(lf, base, rela, ELF_RELOC_RELA,
1265                             elf_obj_lookup);
1266                 }
1267         }
1268 }