The option is not even recognized and with that patched it does not compile. Even if it did work, it would be prohibitively expensive to use. Interested parties can use pmcstat or dtrace instead.
1988 lines
49 KiB
C
1988 lines
49 KiB
C
/*-
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* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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*
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* Copyright (c) 1998-2000 Doug Rabson
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* All rights reserved.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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#include <sys/cdefs.h>
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__FBSDID("$FreeBSD$");
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#include "opt_ddb.h"
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#include "opt_gdb.h"
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#include <sys/param.h>
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#include <sys/systm.h>
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#include <sys/kernel.h>
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#include <sys/lock.h>
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#include <sys/malloc.h>
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#ifdef SPARSE_MAPPING
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#include <sys/mman.h>
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#endif
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#include <sys/mutex.h>
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#include <sys/mount.h>
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#include <sys/pcpu.h>
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#include <sys/proc.h>
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#include <sys/namei.h>
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#include <sys/fcntl.h>
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#include <sys/vnode.h>
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#include <sys/linker.h>
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#include <sys/sysctl.h>
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#include <machine/elf.h>
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#include <net/vnet.h>
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#include <security/mac/mac_framework.h>
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#include <vm/vm.h>
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#include <vm/vm_param.h>
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#ifdef SPARSE_MAPPING
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#include <vm/vm_object.h>
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#include <vm/vm_kern.h>
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#include <vm/vm_extern.h>
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#endif
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#include <vm/pmap.h>
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#include <vm/vm_map.h>
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#include <sys/link_elf.h>
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#include "linker_if.h"
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#define MAXSEGS 4
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typedef struct elf_file {
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struct linker_file lf; /* Common fields */
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int preloaded; /* Was file pre-loaded */
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caddr_t address; /* Relocation address */
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#ifdef SPARSE_MAPPING
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vm_object_t object; /* VM object to hold file pages */
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#endif
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Elf_Dyn *dynamic; /* Symbol table etc. */
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Elf_Hashelt nbuckets; /* DT_HASH info */
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Elf_Hashelt nchains;
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const Elf_Hashelt *buckets;
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const Elf_Hashelt *chains;
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caddr_t hash;
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caddr_t strtab; /* DT_STRTAB */
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int strsz; /* DT_STRSZ */
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const Elf_Sym *symtab; /* DT_SYMTAB */
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Elf_Addr *got; /* DT_PLTGOT */
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const Elf_Rel *pltrel; /* DT_JMPREL */
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int pltrelsize; /* DT_PLTRELSZ */
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const Elf_Rela *pltrela; /* DT_JMPREL */
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int pltrelasize; /* DT_PLTRELSZ */
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const Elf_Rel *rel; /* DT_REL */
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int relsize; /* DT_RELSZ */
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const Elf_Rela *rela; /* DT_RELA */
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int relasize; /* DT_RELASZ */
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caddr_t modptr;
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const Elf_Sym *ddbsymtab; /* The symbol table we are using */
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long ddbsymcnt; /* Number of symbols */
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caddr_t ddbstrtab; /* String table */
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long ddbstrcnt; /* number of bytes in string table */
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caddr_t symbase; /* malloc'ed symbold base */
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caddr_t strbase; /* malloc'ed string base */
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caddr_t ctftab; /* CTF table */
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long ctfcnt; /* number of bytes in CTF table */
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caddr_t ctfoff; /* CTF offset table */
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caddr_t typoff; /* Type offset table */
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long typlen; /* Number of type entries. */
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Elf_Addr pcpu_start; /* Pre-relocation pcpu set start. */
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Elf_Addr pcpu_stop; /* Pre-relocation pcpu set stop. */
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Elf_Addr pcpu_base; /* Relocated pcpu set address. */
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#ifdef VIMAGE
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Elf_Addr vnet_start; /* Pre-relocation vnet set start. */
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Elf_Addr vnet_stop; /* Pre-relocation vnet set stop. */
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Elf_Addr vnet_base; /* Relocated vnet set address. */
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#endif
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#ifdef GDB
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struct link_map gdb; /* hooks for gdb */
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#endif
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} *elf_file_t;
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struct elf_set {
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Elf_Addr es_start;
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Elf_Addr es_stop;
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Elf_Addr es_base;
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TAILQ_ENTRY(elf_set) es_link;
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};
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TAILQ_HEAD(elf_set_head, elf_set);
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#include <kern/kern_ctf.c>
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static int link_elf_link_common_finish(linker_file_t);
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static int link_elf_link_preload(linker_class_t cls,
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const char *, linker_file_t *);
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static int link_elf_link_preload_finish(linker_file_t);
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static int link_elf_load_file(linker_class_t, const char *,
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linker_file_t *);
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static int link_elf_lookup_symbol(linker_file_t, const char *,
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c_linker_sym_t *);
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static int link_elf_lookup_debug_symbol(linker_file_t, const char *,
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c_linker_sym_t *);
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static int link_elf_symbol_values(linker_file_t, c_linker_sym_t,
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linker_symval_t *);
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static int link_elf_debug_symbol_values(linker_file_t, c_linker_sym_t,
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linker_symval_t*);
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static int link_elf_search_symbol(linker_file_t, caddr_t,
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c_linker_sym_t *, long *);
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static void link_elf_unload_file(linker_file_t);
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static void link_elf_unload_preload(linker_file_t);
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static int link_elf_lookup_set(linker_file_t, const char *,
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void ***, void ***, int *);
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static int link_elf_each_function_name(linker_file_t,
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int (*)(const char *, void *), void *);
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static int link_elf_each_function_nameval(linker_file_t,
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linker_function_nameval_callback_t, void *);
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static void link_elf_reloc_local(linker_file_t);
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static long link_elf_symtab_get(linker_file_t, const Elf_Sym **);
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static long link_elf_strtab_get(linker_file_t, caddr_t *);
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static int elf_lookup(linker_file_t, Elf_Size, int, Elf_Addr *);
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static kobj_method_t link_elf_methods[] = {
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KOBJMETHOD(linker_lookup_symbol, link_elf_lookup_symbol),
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KOBJMETHOD(linker_lookup_debug_symbol, link_elf_lookup_debug_symbol),
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KOBJMETHOD(linker_symbol_values, link_elf_symbol_values),
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KOBJMETHOD(linker_debug_symbol_values, link_elf_debug_symbol_values),
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KOBJMETHOD(linker_search_symbol, link_elf_search_symbol),
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KOBJMETHOD(linker_unload, link_elf_unload_file),
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KOBJMETHOD(linker_load_file, link_elf_load_file),
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KOBJMETHOD(linker_link_preload, link_elf_link_preload),
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KOBJMETHOD(linker_link_preload_finish, link_elf_link_preload_finish),
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KOBJMETHOD(linker_lookup_set, link_elf_lookup_set),
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KOBJMETHOD(linker_each_function_name, link_elf_each_function_name),
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KOBJMETHOD(linker_each_function_nameval, link_elf_each_function_nameval),
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KOBJMETHOD(linker_ctf_get, link_elf_ctf_get),
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KOBJMETHOD(linker_symtab_get, link_elf_symtab_get),
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KOBJMETHOD(linker_strtab_get, link_elf_strtab_get),
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KOBJMETHOD_END
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};
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static struct linker_class link_elf_class = {
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#if ELF_TARG_CLASS == ELFCLASS32
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"elf32",
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#else
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"elf64",
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#endif
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link_elf_methods, sizeof(struct elf_file)
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};
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static bool link_elf_leak_locals = true;
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SYSCTL_BOOL(_debug, OID_AUTO, link_elf_leak_locals,
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CTLFLAG_RWTUN, &link_elf_leak_locals, 0,
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"Allow local symbols to participate in global module symbol resolution");
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typedef int (*elf_reloc_fn)(linker_file_t lf, Elf_Addr relocbase,
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const void *data, int type, elf_lookup_fn lookup);
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static int parse_dynamic(elf_file_t);
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static int relocate_file(elf_file_t);
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static int relocate_file1(elf_file_t ef, elf_lookup_fn lookup,
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elf_reloc_fn reloc, bool ifuncs);
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static int link_elf_preload_parse_symbols(elf_file_t);
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static struct elf_set_head set_pcpu_list;
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#ifdef VIMAGE
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static struct elf_set_head set_vnet_list;
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#endif
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static void
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elf_set_add(struct elf_set_head *list, Elf_Addr start, Elf_Addr stop, Elf_Addr base)
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{
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struct elf_set *set, *iter;
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set = malloc(sizeof(*set), M_LINKER, M_WAITOK);
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set->es_start = start;
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set->es_stop = stop;
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set->es_base = base;
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TAILQ_FOREACH(iter, list, es_link) {
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KASSERT((set->es_start < iter->es_start && set->es_stop < iter->es_stop) ||
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(set->es_start > iter->es_start && set->es_stop > iter->es_stop),
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("linker sets intersection: to insert: 0x%jx-0x%jx; inserted: 0x%jx-0x%jx",
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(uintmax_t)set->es_start, (uintmax_t)set->es_stop,
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(uintmax_t)iter->es_start, (uintmax_t)iter->es_stop));
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if (iter->es_start > set->es_start) {
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TAILQ_INSERT_BEFORE(iter, set, es_link);
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break;
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}
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}
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if (iter == NULL)
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TAILQ_INSERT_TAIL(list, set, es_link);
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}
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static int
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elf_set_find(struct elf_set_head *list, Elf_Addr addr, Elf_Addr *start, Elf_Addr *base)
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{
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struct elf_set *set;
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TAILQ_FOREACH(set, list, es_link) {
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if (addr < set->es_start)
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return (0);
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if (addr < set->es_stop) {
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*start = set->es_start;
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*base = set->es_base;
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return (1);
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}
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}
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return (0);
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}
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static void
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elf_set_delete(struct elf_set_head *list, Elf_Addr start)
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{
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struct elf_set *set;
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TAILQ_FOREACH(set, list, es_link) {
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if (start < set->es_start)
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break;
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if (start == set->es_start) {
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TAILQ_REMOVE(list, set, es_link);
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free(set, M_LINKER);
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return;
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}
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}
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KASSERT(0, ("deleting unknown linker set (start = 0x%jx)",
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(uintmax_t)start));
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}
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#ifdef GDB
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static void r_debug_state(struct r_debug *, struct link_map *);
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/*
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* A list of loaded modules for GDB to use for loading symbols.
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*/
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struct r_debug r_debug;
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#define GDB_STATE(s) do { \
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r_debug.r_state = s; r_debug_state(NULL, NULL); \
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} while (0)
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/*
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* Function for the debugger to set a breakpoint on to gain control.
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*/
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static void
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r_debug_state(struct r_debug *dummy_one __unused,
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struct link_map *dummy_two __unused)
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{
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}
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static void
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link_elf_add_gdb(struct link_map *l)
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{
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struct link_map *prev;
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l->l_next = NULL;
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if (r_debug.r_map == NULL) {
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/* Add first. */
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l->l_prev = NULL;
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r_debug.r_map = l;
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} else {
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/* Append to list. */
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for (prev = r_debug.r_map;
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prev->l_next != NULL;
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prev = prev->l_next)
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;
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l->l_prev = prev;
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prev->l_next = l;
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}
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}
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static void
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link_elf_delete_gdb(struct link_map *l)
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{
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if (l->l_prev == NULL) {
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/* Remove first. */
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if ((r_debug.r_map = l->l_next) != NULL)
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l->l_next->l_prev = NULL;
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} else {
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/* Remove any but first. */
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if ((l->l_prev->l_next = l->l_next) != NULL)
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l->l_next->l_prev = l->l_prev;
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}
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}
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#endif /* GDB */
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/*
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* The kernel symbol table starts here.
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*/
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extern struct _dynamic _DYNAMIC;
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static void
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link_elf_error(const char *filename, const char *s)
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{
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if (filename == NULL)
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printf("kldload: %s\n", s);
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else
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printf("kldload: %s: %s\n", filename, s);
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}
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static void
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link_elf_invoke_ctors(caddr_t addr, size_t size)
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{
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void (**ctor)(void);
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size_t i, cnt;
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if (addr == NULL || size == 0)
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return;
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cnt = size / sizeof(*ctor);
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ctor = (void *)addr;
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for (i = 0; i < cnt; i++) {
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if (ctor[i] != NULL)
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(*ctor[i])();
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}
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}
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/*
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* Actions performed after linking/loading both the preloaded kernel and any
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* modules; whether preloaded or dynamicly loaded.
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*/
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static int
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link_elf_link_common_finish(linker_file_t lf)
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{
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#ifdef GDB
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elf_file_t ef = (elf_file_t)lf;
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char *newfilename;
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#endif
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int error;
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/* Notify MD code that a module is being loaded. */
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error = elf_cpu_load_file(lf);
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if (error != 0)
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return (error);
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#ifdef GDB
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GDB_STATE(RT_ADD);
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ef->gdb.l_addr = lf->address;
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newfilename = malloc(strlen(lf->filename) + 1, M_LINKER, M_WAITOK);
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strcpy(newfilename, lf->filename);
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ef->gdb.l_name = newfilename;
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ef->gdb.l_ld = ef->dynamic;
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link_elf_add_gdb(&ef->gdb);
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GDB_STATE(RT_CONSISTENT);
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#endif
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/* Invoke .ctors */
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link_elf_invoke_ctors(lf->ctors_addr, lf->ctors_size);
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return (0);
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}
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#ifdef RELOCATABLE_KERNEL
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/*
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* __startkernel and __endkernel are symbols set up as relocation canaries.
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*
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* They are defined in locore to reference linker script symbols at the
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* beginning and end of the LOAD area. This has the desired side effect of
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* giving us variables that have relative relocations pointing at them, so
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* relocation of the kernel object will cause the variables to be updated
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* automatically by the runtime linker when we initialize.
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*
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* There are two main reasons to relocate the kernel:
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* 1) If the loader needed to load the kernel at an alternate load address.
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* 2) If the kernel is switching address spaces on machines like POWER9
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* under Radix where the high bits of the effective address are used to
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|
* differentiate between hypervisor, host, guest, and problem state.
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*/
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extern vm_offset_t __startkernel, __endkernel;
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#endif
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static unsigned long kern_relbase = KERNBASE;
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SYSCTL_ULONG(_kern, OID_AUTO, base_address, CTLFLAG_RD,
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SYSCTL_NULL_ULONG_PTR, KERNBASE, "Kernel base address");
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SYSCTL_ULONG(_kern, OID_AUTO, relbase_address, CTLFLAG_RD,
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&kern_relbase, 0, "Kernel relocated base address");
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|
static void
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link_elf_init(void* arg)
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{
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Elf_Dyn *dp;
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Elf_Addr *ctors_addrp;
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|
Elf_Size *ctors_sizep;
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|
caddr_t modptr, baseptr, sizeptr;
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elf_file_t ef;
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const char *modname;
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linker_add_class(&link_elf_class);
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dp = (Elf_Dyn *)&_DYNAMIC;
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modname = NULL;
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modptr = preload_search_by_type("elf" __XSTRING(__ELF_WORD_SIZE) " kernel");
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if (modptr == NULL)
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modptr = preload_search_by_type("elf kernel");
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modname = (char *)preload_search_info(modptr, MODINFO_NAME);
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if (modname == NULL)
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modname = "kernel";
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linker_kernel_file = linker_make_file(modname, &link_elf_class);
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if (linker_kernel_file == NULL)
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panic("%s: Can't create linker structures for kernel",
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__func__);
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ef = (elf_file_t) linker_kernel_file;
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ef->preloaded = 1;
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#ifdef RELOCATABLE_KERNEL
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/* Compute relative displacement */
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ef->address = (caddr_t) (__startkernel - KERNBASE);
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#else
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ef->address = 0;
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#endif
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#ifdef SPARSE_MAPPING
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ef->object = NULL;
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#endif
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ef->dynamic = dp;
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if (dp != NULL)
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parse_dynamic(ef);
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#ifdef RELOCATABLE_KERNEL
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linker_kernel_file->address = (caddr_t)__startkernel;
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linker_kernel_file->size = (intptr_t)(__endkernel - __startkernel);
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kern_relbase = (unsigned long)__startkernel;
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#else
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linker_kernel_file->address += KERNBASE;
|
|
linker_kernel_file->size = -(intptr_t)linker_kernel_file->address;
|
|
#endif
|
|
|
|
if (modptr != NULL) {
|
|
ef->modptr = modptr;
|
|
baseptr = preload_search_info(modptr, MODINFO_ADDR);
|
|
if (baseptr != NULL)
|
|
linker_kernel_file->address = *(caddr_t *)baseptr;
|
|
sizeptr = preload_search_info(modptr, MODINFO_SIZE);
|
|
if (sizeptr != NULL)
|
|
linker_kernel_file->size = *(size_t *)sizeptr;
|
|
ctors_addrp = (Elf_Addr *)preload_search_info(modptr,
|
|
MODINFO_METADATA | MODINFOMD_CTORS_ADDR);
|
|
ctors_sizep = (Elf_Size *)preload_search_info(modptr,
|
|
MODINFO_METADATA | MODINFOMD_CTORS_SIZE);
|
|
if (ctors_addrp != NULL && ctors_sizep != NULL) {
|
|
linker_kernel_file->ctors_addr = ef->address +
|
|
*ctors_addrp;
|
|
linker_kernel_file->ctors_size = *ctors_sizep;
|
|
}
|
|
}
|
|
(void)link_elf_preload_parse_symbols(ef);
|
|
|
|
#ifdef GDB
|
|
r_debug.r_map = NULL;
|
|
r_debug.r_brk = r_debug_state;
|
|
r_debug.r_state = RT_CONSISTENT;
|
|
#endif
|
|
|
|
(void)link_elf_link_common_finish(linker_kernel_file);
|
|
linker_kernel_file->flags |= LINKER_FILE_LINKED;
|
|
TAILQ_INIT(&set_pcpu_list);
|
|
#ifdef VIMAGE
|
|
TAILQ_INIT(&set_vnet_list);
|
|
#endif
|
|
}
|
|
|
|
SYSINIT(link_elf, SI_SUB_KLD, SI_ORDER_THIRD, link_elf_init, NULL);
|
|
|
|
static int
|
|
link_elf_preload_parse_symbols(elf_file_t ef)
|
|
{
|
|
caddr_t pointer;
|
|
caddr_t ssym, esym, base;
|
|
caddr_t strtab;
|
|
int strcnt;
|
|
Elf_Sym *symtab;
|
|
int symcnt;
|
|
|
|
if (ef->modptr == NULL)
|
|
return (0);
|
|
pointer = preload_search_info(ef->modptr,
|
|
MODINFO_METADATA | MODINFOMD_SSYM);
|
|
if (pointer == NULL)
|
|
return (0);
|
|
ssym = *(caddr_t *)pointer;
|
|
pointer = preload_search_info(ef->modptr,
|
|
MODINFO_METADATA | MODINFOMD_ESYM);
|
|
if (pointer == NULL)
|
|
return (0);
|
|
esym = *(caddr_t *)pointer;
|
|
|
|
base = ssym;
|
|
|
|
symcnt = *(long *)base;
|
|
base += sizeof(long);
|
|
symtab = (Elf_Sym *)base;
|
|
base += roundup(symcnt, sizeof(long));
|
|
|
|
if (base > esym || base < ssym) {
|
|
printf("Symbols are corrupt!\n");
|
|
return (EINVAL);
|
|
}
|
|
|
|
strcnt = *(long *)base;
|
|
base += sizeof(long);
|
|
strtab = base;
|
|
base += roundup(strcnt, sizeof(long));
|
|
|
|
if (base > esym || base < ssym) {
|
|
printf("Symbols are corrupt!\n");
|
|
return (EINVAL);
|
|
}
|
|
|
|
ef->ddbsymtab = symtab;
|
|
ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
|
|
ef->ddbstrtab = strtab;
|
|
ef->ddbstrcnt = strcnt;
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
parse_dynamic(elf_file_t ef)
|
|
{
|
|
Elf_Dyn *dp;
|
|
int plttype = DT_REL;
|
|
|
|
for (dp = ef->dynamic; dp->d_tag != DT_NULL; dp++) {
|
|
switch (dp->d_tag) {
|
|
case DT_HASH:
|
|
{
|
|
/* From src/libexec/rtld-elf/rtld.c */
|
|
const Elf_Hashelt *hashtab = (const Elf_Hashelt *)
|
|
(ef->address + dp->d_un.d_ptr);
|
|
ef->nbuckets = hashtab[0];
|
|
ef->nchains = hashtab[1];
|
|
ef->buckets = hashtab + 2;
|
|
ef->chains = ef->buckets + ef->nbuckets;
|
|
break;
|
|
}
|
|
case DT_STRTAB:
|
|
ef->strtab = (caddr_t) (ef->address + dp->d_un.d_ptr);
|
|
break;
|
|
case DT_STRSZ:
|
|
ef->strsz = dp->d_un.d_val;
|
|
break;
|
|
case DT_SYMTAB:
|
|
ef->symtab = (Elf_Sym*) (ef->address + dp->d_un.d_ptr);
|
|
break;
|
|
case DT_SYMENT:
|
|
if (dp->d_un.d_val != sizeof(Elf_Sym))
|
|
return (ENOEXEC);
|
|
break;
|
|
case DT_PLTGOT:
|
|
ef->got = (Elf_Addr *) (ef->address + dp->d_un.d_ptr);
|
|
break;
|
|
case DT_REL:
|
|
ef->rel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
|
|
break;
|
|
case DT_RELSZ:
|
|
ef->relsize = dp->d_un.d_val;
|
|
break;
|
|
case DT_RELENT:
|
|
if (dp->d_un.d_val != sizeof(Elf_Rel))
|
|
return (ENOEXEC);
|
|
break;
|
|
case DT_JMPREL:
|
|
ef->pltrel = (const Elf_Rel *) (ef->address + dp->d_un.d_ptr);
|
|
break;
|
|
case DT_PLTRELSZ:
|
|
ef->pltrelsize = dp->d_un.d_val;
|
|
break;
|
|
case DT_RELA:
|
|
ef->rela = (const Elf_Rela *) (ef->address + dp->d_un.d_ptr);
|
|
break;
|
|
case DT_RELASZ:
|
|
ef->relasize = dp->d_un.d_val;
|
|
break;
|
|
case DT_RELAENT:
|
|
if (dp->d_un.d_val != sizeof(Elf_Rela))
|
|
return (ENOEXEC);
|
|
break;
|
|
case DT_PLTREL:
|
|
plttype = dp->d_un.d_val;
|
|
if (plttype != DT_REL && plttype != DT_RELA)
|
|
return (ENOEXEC);
|
|
break;
|
|
#ifdef GDB
|
|
case DT_DEBUG:
|
|
dp->d_un.d_ptr = (Elf_Addr)&r_debug;
|
|
break;
|
|
#endif
|
|
}
|
|
}
|
|
|
|
if (plttype == DT_RELA) {
|
|
ef->pltrela = (const Elf_Rela *)ef->pltrel;
|
|
ef->pltrel = NULL;
|
|
ef->pltrelasize = ef->pltrelsize;
|
|
ef->pltrelsize = 0;
|
|
}
|
|
|
|
ef->ddbsymtab = ef->symtab;
|
|
ef->ddbsymcnt = ef->nchains;
|
|
ef->ddbstrtab = ef->strtab;
|
|
ef->ddbstrcnt = ef->strsz;
|
|
|
|
return elf_cpu_parse_dynamic(ef->address, ef->dynamic);
|
|
}
|
|
|
|
#define LS_PADDING 0x90909090
|
|
static int
|
|
parse_dpcpu(elf_file_t ef)
|
|
{
|
|
int error, size;
|
|
#if defined(__i386__)
|
|
uint32_t pad;
|
|
#endif
|
|
|
|
ef->pcpu_start = 0;
|
|
ef->pcpu_stop = 0;
|
|
error = link_elf_lookup_set(&ef->lf, "pcpu", (void ***)&ef->pcpu_start,
|
|
(void ***)&ef->pcpu_stop, NULL);
|
|
/* Error just means there is no pcpu set to relocate. */
|
|
if (error != 0)
|
|
return (0);
|
|
size = (uintptr_t)ef->pcpu_stop - (uintptr_t)ef->pcpu_start;
|
|
/* Empty set? */
|
|
if (size < 1)
|
|
return (0);
|
|
#if defined(__i386__)
|
|
/* In case we do find __start/stop_set_ symbols double-check. */
|
|
if (size < 4) {
|
|
uprintf("Kernel module '%s' must be recompiled with "
|
|
"linker script\n", ef->lf.pathname);
|
|
return (ENOEXEC);
|
|
}
|
|
|
|
/* Padding from linker-script correct? */
|
|
pad = *(uint32_t *)((uintptr_t)ef->pcpu_stop - sizeof(pad));
|
|
if (pad != LS_PADDING) {
|
|
uprintf("Kernel module '%s' must be recompiled with "
|
|
"linker script, invalid padding %#04x (%#04x)\n",
|
|
ef->lf.pathname, pad, LS_PADDING);
|
|
return (ENOEXEC);
|
|
}
|
|
/* If we only have valid padding, nothing to do. */
|
|
if (size == 4)
|
|
return (0);
|
|
#endif
|
|
/*
|
|
* Allocate space in the primary pcpu area. Copy in our
|
|
* initialization from the data section and then initialize
|
|
* all per-cpu storage from that.
|
|
*/
|
|
ef->pcpu_base = (Elf_Addr)(uintptr_t)dpcpu_alloc(size);
|
|
if (ef->pcpu_base == 0) {
|
|
printf("%s: pcpu module space is out of space; "
|
|
"cannot allocate %d for %s\n",
|
|
__func__, size, ef->lf.pathname);
|
|
return (ENOSPC);
|
|
}
|
|
memcpy((void *)ef->pcpu_base, (void *)ef->pcpu_start, size);
|
|
dpcpu_copy((void *)ef->pcpu_base, size);
|
|
elf_set_add(&set_pcpu_list, ef->pcpu_start, ef->pcpu_stop,
|
|
ef->pcpu_base);
|
|
|
|
return (0);
|
|
}
|
|
|
|
#ifdef VIMAGE
|
|
static int
|
|
parse_vnet(elf_file_t ef)
|
|
{
|
|
int error, size;
|
|
#if defined(__i386__)
|
|
uint32_t pad;
|
|
#endif
|
|
|
|
ef->vnet_start = 0;
|
|
ef->vnet_stop = 0;
|
|
error = link_elf_lookup_set(&ef->lf, "vnet", (void ***)&ef->vnet_start,
|
|
(void ***)&ef->vnet_stop, NULL);
|
|
/* Error just means there is no vnet data set to relocate. */
|
|
if (error != 0)
|
|
return (0);
|
|
size = (uintptr_t)ef->vnet_stop - (uintptr_t)ef->vnet_start;
|
|
/* Empty set? */
|
|
if (size < 1)
|
|
return (0);
|
|
#if defined(__i386__)
|
|
/* In case we do find __start/stop_set_ symbols double-check. */
|
|
if (size < 4) {
|
|
uprintf("Kernel module '%s' must be recompiled with "
|
|
"linker script\n", ef->lf.pathname);
|
|
return (ENOEXEC);
|
|
}
|
|
|
|
/* Padding from linker-script correct? */
|
|
pad = *(uint32_t *)((uintptr_t)ef->vnet_stop - sizeof(pad));
|
|
if (pad != LS_PADDING) {
|
|
uprintf("Kernel module '%s' must be recompiled with "
|
|
"linker script, invalid padding %#04x (%#04x)\n",
|
|
ef->lf.pathname, pad, LS_PADDING);
|
|
return (ENOEXEC);
|
|
}
|
|
/* If we only have valid padding, nothing to do. */
|
|
if (size == 4)
|
|
return (0);
|
|
#endif
|
|
/*
|
|
* Allocate space in the primary vnet area. Copy in our
|
|
* initialization from the data section and then initialize
|
|
* all per-vnet storage from that.
|
|
*/
|
|
ef->vnet_base = (Elf_Addr)(uintptr_t)vnet_data_alloc(size);
|
|
if (ef->vnet_base == 0) {
|
|
printf("%s: vnet module space is out of space; "
|
|
"cannot allocate %d for %s\n",
|
|
__func__, size, ef->lf.pathname);
|
|
return (ENOSPC);
|
|
}
|
|
memcpy((void *)ef->vnet_base, (void *)ef->vnet_start, size);
|
|
vnet_data_copy((void *)ef->vnet_base, size);
|
|
elf_set_add(&set_vnet_list, ef->vnet_start, ef->vnet_stop,
|
|
ef->vnet_base);
|
|
|
|
return (0);
|
|
}
|
|
#endif
|
|
#undef LS_PADDING
|
|
|
|
/*
|
|
* Apply the specified protection to the loadable segments of a preloaded linker
|
|
* file.
|
|
*/
|
|
static int
|
|
preload_protect(elf_file_t ef, vm_prot_t prot)
|
|
{
|
|
#if defined(__aarch64__) || defined(__amd64__)
|
|
Elf_Ehdr *hdr;
|
|
Elf_Phdr *phdr, *phlimit;
|
|
vm_prot_t nprot;
|
|
int error;
|
|
|
|
error = 0;
|
|
hdr = (Elf_Ehdr *)ef->address;
|
|
phdr = (Elf_Phdr *)(ef->address + hdr->e_phoff);
|
|
phlimit = phdr + hdr->e_phnum;
|
|
for (; phdr < phlimit; phdr++) {
|
|
if (phdr->p_type != PT_LOAD)
|
|
continue;
|
|
|
|
nprot = prot | VM_PROT_READ;
|
|
if ((phdr->p_flags & PF_W) != 0)
|
|
nprot |= VM_PROT_WRITE;
|
|
if ((phdr->p_flags & PF_X) != 0)
|
|
nprot |= VM_PROT_EXECUTE;
|
|
error = pmap_change_prot((vm_offset_t)ef->address +
|
|
phdr->p_vaddr, round_page(phdr->p_memsz), nprot);
|
|
if (error != 0)
|
|
break;
|
|
}
|
|
return (error);
|
|
#else
|
|
return (0);
|
|
#endif
|
|
}
|
|
|
|
#ifdef __arm__
|
|
/*
|
|
* Locate the ARM exception/unwind table info for DDB and stack(9) use by
|
|
* searching for the section header that describes it. There may be no unwind
|
|
* info, for example in a module containing only data.
|
|
*/
|
|
static void
|
|
link_elf_locate_exidx(linker_file_t lf, Elf_Shdr *shdr, int nhdr)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < nhdr; i++) {
|
|
if (shdr[i].sh_type == SHT_ARM_EXIDX) {
|
|
lf->exidx_addr = shdr[i].sh_addr + lf->address;
|
|
lf->exidx_size = shdr[i].sh_size;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Locate the section headers metadata in a preloaded module, then use it to
|
|
* locate the exception/unwind table in the module. The size of the metadata
|
|
* block is stored in a uint32 word immediately before the data itself, and a
|
|
* comment in preload_search_info() says it is safe to rely on that.
|
|
*/
|
|
static void
|
|
link_elf_locate_exidx_preload(struct linker_file *lf, caddr_t modptr)
|
|
{
|
|
uint32_t *modinfo;
|
|
Elf_Shdr *shdr;
|
|
uint32_t nhdr;
|
|
|
|
modinfo = (uint32_t *)preload_search_info(modptr,
|
|
MODINFO_METADATA | MODINFOMD_SHDR);
|
|
if (modinfo != NULL) {
|
|
shdr = (Elf_Shdr *)modinfo;
|
|
nhdr = modinfo[-1] / sizeof(Elf_Shdr);
|
|
link_elf_locate_exidx(lf, shdr, nhdr);
|
|
}
|
|
}
|
|
|
|
#endif /* __arm__ */
|
|
|
|
static int
|
|
link_elf_link_preload(linker_class_t cls, const char *filename,
|
|
linker_file_t *result)
|
|
{
|
|
Elf_Addr *ctors_addrp;
|
|
Elf_Size *ctors_sizep;
|
|
caddr_t modptr, baseptr, sizeptr, dynptr;
|
|
char *type;
|
|
elf_file_t ef;
|
|
linker_file_t lf;
|
|
int error;
|
|
vm_offset_t dp;
|
|
|
|
/* Look to see if we have the file preloaded */
|
|
modptr = preload_search_by_name(filename);
|
|
if (modptr == NULL)
|
|
return (ENOENT);
|
|
|
|
type = (char *)preload_search_info(modptr, MODINFO_TYPE);
|
|
baseptr = preload_search_info(modptr, MODINFO_ADDR);
|
|
sizeptr = preload_search_info(modptr, MODINFO_SIZE);
|
|
dynptr = preload_search_info(modptr,
|
|
MODINFO_METADATA | MODINFOMD_DYNAMIC);
|
|
if (type == NULL ||
|
|
(strcmp(type, "elf" __XSTRING(__ELF_WORD_SIZE) " module") != 0 &&
|
|
strcmp(type, "elf module") != 0))
|
|
return (EFTYPE);
|
|
if (baseptr == NULL || sizeptr == NULL || dynptr == NULL)
|
|
return (EINVAL);
|
|
|
|
lf = linker_make_file(filename, &link_elf_class);
|
|
if (lf == NULL)
|
|
return (ENOMEM);
|
|
|
|
ef = (elf_file_t) lf;
|
|
ef->preloaded = 1;
|
|
ef->modptr = modptr;
|
|
ef->address = *(caddr_t *)baseptr;
|
|
#ifdef SPARSE_MAPPING
|
|
ef->object = NULL;
|
|
#endif
|
|
dp = (vm_offset_t)ef->address + *(vm_offset_t *)dynptr;
|
|
ef->dynamic = (Elf_Dyn *)dp;
|
|
lf->address = ef->address;
|
|
lf->size = *(size_t *)sizeptr;
|
|
|
|
ctors_addrp = (Elf_Addr *)preload_search_info(modptr,
|
|
MODINFO_METADATA | MODINFOMD_CTORS_ADDR);
|
|
ctors_sizep = (Elf_Size *)preload_search_info(modptr,
|
|
MODINFO_METADATA | MODINFOMD_CTORS_SIZE);
|
|
if (ctors_addrp != NULL && ctors_sizep != NULL) {
|
|
lf->ctors_addr = ef->address + *ctors_addrp;
|
|
lf->ctors_size = *ctors_sizep;
|
|
}
|
|
|
|
#ifdef __arm__
|
|
link_elf_locate_exidx_preload(lf, modptr);
|
|
#endif
|
|
|
|
error = parse_dynamic(ef);
|
|
if (error == 0)
|
|
error = parse_dpcpu(ef);
|
|
#ifdef VIMAGE
|
|
if (error == 0)
|
|
error = parse_vnet(ef);
|
|
#endif
|
|
if (error == 0)
|
|
error = preload_protect(ef, VM_PROT_ALL);
|
|
if (error != 0) {
|
|
linker_file_unload(lf, LINKER_UNLOAD_FORCE);
|
|
return (error);
|
|
}
|
|
link_elf_reloc_local(lf);
|
|
*result = lf;
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
link_elf_link_preload_finish(linker_file_t lf)
|
|
{
|
|
elf_file_t ef;
|
|
int error;
|
|
|
|
ef = (elf_file_t) lf;
|
|
error = relocate_file(ef);
|
|
if (error == 0)
|
|
error = preload_protect(ef, VM_PROT_NONE);
|
|
if (error != 0)
|
|
return (error);
|
|
(void)link_elf_preload_parse_symbols(ef);
|
|
|
|
return (link_elf_link_common_finish(lf));
|
|
}
|
|
|
|
static int
|
|
link_elf_load_file(linker_class_t cls, const char* filename,
|
|
linker_file_t* result)
|
|
{
|
|
struct nameidata nd;
|
|
struct thread* td = curthread; /* XXX */
|
|
Elf_Ehdr *hdr;
|
|
caddr_t firstpage, segbase;
|
|
int nbytes, i;
|
|
Elf_Phdr *phdr;
|
|
Elf_Phdr *phlimit;
|
|
Elf_Phdr *segs[MAXSEGS];
|
|
int nsegs;
|
|
Elf_Phdr *phdyn;
|
|
caddr_t mapbase;
|
|
size_t mapsize;
|
|
Elf_Addr base_vaddr;
|
|
Elf_Addr base_vlimit;
|
|
int error = 0;
|
|
ssize_t resid;
|
|
int flags;
|
|
elf_file_t ef;
|
|
linker_file_t lf;
|
|
Elf_Shdr *shdr;
|
|
int symtabindex;
|
|
int symstrindex;
|
|
int shstrindex;
|
|
int symcnt;
|
|
int strcnt;
|
|
char *shstrs;
|
|
|
|
shdr = NULL;
|
|
lf = NULL;
|
|
shstrs = NULL;
|
|
|
|
NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, filename);
|
|
flags = FREAD;
|
|
error = vn_open(&nd, &flags, 0, NULL);
|
|
if (error != 0)
|
|
return (error);
|
|
NDFREE_PNBUF(&nd);
|
|
if (nd.ni_vp->v_type != VREG) {
|
|
error = ENOEXEC;
|
|
firstpage = NULL;
|
|
goto out;
|
|
}
|
|
#ifdef MAC
|
|
error = mac_kld_check_load(curthread->td_ucred, nd.ni_vp);
|
|
if (error != 0) {
|
|
firstpage = NULL;
|
|
goto out;
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Read the elf header from the file.
|
|
*/
|
|
firstpage = malloc(PAGE_SIZE, M_LINKER, M_WAITOK);
|
|
hdr = (Elf_Ehdr *)firstpage;
|
|
error = vn_rdwr(UIO_READ, nd.ni_vp, firstpage, PAGE_SIZE, 0,
|
|
UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
|
|
&resid, td);
|
|
nbytes = PAGE_SIZE - resid;
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
if (!IS_ELF(*hdr)) {
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
|
|
if (hdr->e_ident[EI_CLASS] != ELF_TARG_CLASS ||
|
|
hdr->e_ident[EI_DATA] != ELF_TARG_DATA) {
|
|
link_elf_error(filename, "Unsupported file layout");
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
if (hdr->e_ident[EI_VERSION] != EV_CURRENT ||
|
|
hdr->e_version != EV_CURRENT) {
|
|
link_elf_error(filename, "Unsupported file version");
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
if (hdr->e_type != ET_EXEC && hdr->e_type != ET_DYN) {
|
|
error = ENOSYS;
|
|
goto out;
|
|
}
|
|
if (hdr->e_machine != ELF_TARG_MACH) {
|
|
link_elf_error(filename, "Unsupported machine");
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* We rely on the program header being in the first page.
|
|
* This is not strictly required by the ABI specification, but
|
|
* it seems to always true in practice. And, it simplifies
|
|
* things considerably.
|
|
*/
|
|
if (!((hdr->e_phentsize == sizeof(Elf_Phdr)) &&
|
|
(hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= PAGE_SIZE) &&
|
|
(hdr->e_phoff + hdr->e_phnum*sizeof(Elf_Phdr) <= nbytes)))
|
|
link_elf_error(filename, "Unreadable program headers");
|
|
|
|
/*
|
|
* Scan the program header entries, and save key information.
|
|
*
|
|
* We rely on there being exactly two load segments, text and data,
|
|
* in that order.
|
|
*/
|
|
phdr = (Elf_Phdr *) (firstpage + hdr->e_phoff);
|
|
phlimit = phdr + hdr->e_phnum;
|
|
nsegs = 0;
|
|
phdyn = NULL;
|
|
while (phdr < phlimit) {
|
|
switch (phdr->p_type) {
|
|
case PT_LOAD:
|
|
if (nsegs == MAXSEGS) {
|
|
link_elf_error(filename, "Too many sections");
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
/*
|
|
* XXX: We just trust they come in right order ??
|
|
*/
|
|
segs[nsegs] = phdr;
|
|
++nsegs;
|
|
break;
|
|
|
|
case PT_DYNAMIC:
|
|
phdyn = phdr;
|
|
break;
|
|
|
|
case PT_INTERP:
|
|
error = ENOSYS;
|
|
goto out;
|
|
}
|
|
|
|
++phdr;
|
|
}
|
|
if (phdyn == NULL) {
|
|
link_elf_error(filename, "Object is not dynamically-linked");
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
if (nsegs == 0) {
|
|
link_elf_error(filename, "No sections");
|
|
error = ENOEXEC;
|
|
goto out;
|
|
}
|
|
|
|
/*
|
|
* Allocate the entire address space of the object, to stake
|
|
* out our contiguous region, and to establish the base
|
|
* address for relocation.
|
|
*/
|
|
base_vaddr = trunc_page(segs[0]->p_vaddr);
|
|
base_vlimit = round_page(segs[nsegs - 1]->p_vaddr +
|
|
segs[nsegs - 1]->p_memsz);
|
|
mapsize = base_vlimit - base_vaddr;
|
|
|
|
lf = linker_make_file(filename, &link_elf_class);
|
|
if (lf == NULL) {
|
|
error = ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
ef = (elf_file_t) lf;
|
|
#ifdef SPARSE_MAPPING
|
|
ef->object = vm_pager_allocate(OBJT_PHYS, NULL, mapsize, VM_PROT_ALL,
|
|
0, thread0.td_ucred);
|
|
if (ef->object == NULL) {
|
|
error = ENOMEM;
|
|
goto out;
|
|
}
|
|
#ifdef __amd64__
|
|
mapbase = (caddr_t)KERNBASE;
|
|
#else
|
|
mapbase = (caddr_t)vm_map_min(kernel_map);
|
|
#endif
|
|
/*
|
|
* Mapping protections are downgraded after relocation processing.
|
|
*/
|
|
error = vm_map_find(kernel_map, ef->object, 0,
|
|
(vm_offset_t *)&mapbase, mapsize, 0, VMFS_OPTIMAL_SPACE,
|
|
VM_PROT_ALL, VM_PROT_ALL, 0);
|
|
if (error != 0) {
|
|
vm_object_deallocate(ef->object);
|
|
ef->object = NULL;
|
|
goto out;
|
|
}
|
|
#else
|
|
mapbase = malloc_exec(mapsize, M_LINKER, M_WAITOK);
|
|
#endif
|
|
ef->address = mapbase;
|
|
|
|
/*
|
|
* Read the text and data sections and zero the bss.
|
|
*/
|
|
for (i = 0; i < nsegs; i++) {
|
|
segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
|
|
|
|
#ifdef SPARSE_MAPPING
|
|
/*
|
|
* Consecutive segments may have different mapping permissions,
|
|
* so be strict and verify that their mappings do not overlap.
|
|
*/
|
|
if (((vm_offset_t)segbase & PAGE_MASK) != 0) {
|
|
error = EINVAL;
|
|
goto out;
|
|
}
|
|
|
|
error = vm_map_wire(kernel_map,
|
|
(vm_offset_t)segbase,
|
|
(vm_offset_t)segbase + round_page(segs[i]->p_memsz),
|
|
VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES);
|
|
if (error != KERN_SUCCESS) {
|
|
error = ENOMEM;
|
|
goto out;
|
|
}
|
|
#endif
|
|
|
|
error = vn_rdwr(UIO_READ, nd.ni_vp,
|
|
segbase, segs[i]->p_filesz, segs[i]->p_offset,
|
|
UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
|
|
&resid, td);
|
|
if (error != 0)
|
|
goto out;
|
|
bzero(segbase + segs[i]->p_filesz,
|
|
segs[i]->p_memsz - segs[i]->p_filesz);
|
|
}
|
|
|
|
ef->dynamic = (Elf_Dyn *) (mapbase + phdyn->p_vaddr - base_vaddr);
|
|
|
|
lf->address = ef->address;
|
|
lf->size = mapsize;
|
|
|
|
error = parse_dynamic(ef);
|
|
if (error != 0)
|
|
goto out;
|
|
error = parse_dpcpu(ef);
|
|
if (error != 0)
|
|
goto out;
|
|
#ifdef VIMAGE
|
|
error = parse_vnet(ef);
|
|
if (error != 0)
|
|
goto out;
|
|
#endif
|
|
link_elf_reloc_local(lf);
|
|
|
|
VOP_UNLOCK(nd.ni_vp);
|
|
error = linker_load_dependencies(lf);
|
|
vn_lock(nd.ni_vp, LK_EXCLUSIVE | LK_RETRY);
|
|
if (error != 0)
|
|
goto out;
|
|
error = relocate_file(ef);
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
#ifdef SPARSE_MAPPING
|
|
/*
|
|
* Downgrade permissions on text segment mappings now that relocation
|
|
* processing is complete. Restrict permissions on read-only segments.
|
|
*/
|
|
for (i = 0; i < nsegs; i++) {
|
|
vm_prot_t prot;
|
|
|
|
if (segs[i]->p_type != PT_LOAD)
|
|
continue;
|
|
|
|
prot = VM_PROT_READ;
|
|
if ((segs[i]->p_flags & PF_W) != 0)
|
|
prot |= VM_PROT_WRITE;
|
|
if ((segs[i]->p_flags & PF_X) != 0)
|
|
prot |= VM_PROT_EXECUTE;
|
|
segbase = mapbase + segs[i]->p_vaddr - base_vaddr;
|
|
error = vm_map_protect(kernel_map,
|
|
(vm_offset_t)segbase,
|
|
(vm_offset_t)segbase + round_page(segs[i]->p_memsz),
|
|
prot, 0, VM_MAP_PROTECT_SET_PROT);
|
|
if (error != KERN_SUCCESS) {
|
|
error = ENOMEM;
|
|
goto out;
|
|
}
|
|
}
|
|
#endif
|
|
|
|
/*
|
|
* Try and load the symbol table if it's present. (you can
|
|
* strip it!)
|
|
*/
|
|
nbytes = hdr->e_shnum * hdr->e_shentsize;
|
|
if (nbytes == 0 || hdr->e_shoff == 0)
|
|
goto nosyms;
|
|
shdr = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
|
|
error = vn_rdwr(UIO_READ, nd.ni_vp,
|
|
(caddr_t)shdr, nbytes, hdr->e_shoff,
|
|
UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
|
|
&resid, td);
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
/* Read section string table */
|
|
shstrindex = hdr->e_shstrndx;
|
|
if (shstrindex != 0 && shdr[shstrindex].sh_type == SHT_STRTAB &&
|
|
shdr[shstrindex].sh_size != 0) {
|
|
nbytes = shdr[shstrindex].sh_size;
|
|
shstrs = malloc(nbytes, M_LINKER, M_WAITOK | M_ZERO);
|
|
error = vn_rdwr(UIO_READ, nd.ni_vp, (caddr_t)shstrs, nbytes,
|
|
shdr[shstrindex].sh_offset, UIO_SYSSPACE, IO_NODELOCKED,
|
|
td->td_ucred, NOCRED, &resid, td);
|
|
if (error)
|
|
goto out;
|
|
}
|
|
|
|
symtabindex = -1;
|
|
symstrindex = -1;
|
|
for (i = 0; i < hdr->e_shnum; i++) {
|
|
if (shdr[i].sh_type == SHT_SYMTAB) {
|
|
symtabindex = i;
|
|
symstrindex = shdr[i].sh_link;
|
|
} else if (shstrs != NULL && shdr[i].sh_name != 0 &&
|
|
strcmp(shstrs + shdr[i].sh_name, ".ctors") == 0) {
|
|
/* Record relocated address and size of .ctors. */
|
|
lf->ctors_addr = mapbase + shdr[i].sh_addr - base_vaddr;
|
|
lf->ctors_size = shdr[i].sh_size;
|
|
}
|
|
}
|
|
if (symtabindex < 0 || symstrindex < 0)
|
|
goto nosyms;
|
|
|
|
symcnt = shdr[symtabindex].sh_size;
|
|
ef->symbase = malloc(symcnt, M_LINKER, M_WAITOK);
|
|
strcnt = shdr[symstrindex].sh_size;
|
|
ef->strbase = malloc(strcnt, M_LINKER, M_WAITOK);
|
|
|
|
error = vn_rdwr(UIO_READ, nd.ni_vp,
|
|
ef->symbase, symcnt, shdr[symtabindex].sh_offset,
|
|
UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
|
|
&resid, td);
|
|
if (error != 0)
|
|
goto out;
|
|
error = vn_rdwr(UIO_READ, nd.ni_vp,
|
|
ef->strbase, strcnt, shdr[symstrindex].sh_offset,
|
|
UIO_SYSSPACE, IO_NODELOCKED, td->td_ucred, NOCRED,
|
|
&resid, td);
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
ef->ddbsymcnt = symcnt / sizeof(Elf_Sym);
|
|
ef->ddbsymtab = (const Elf_Sym *)ef->symbase;
|
|
ef->ddbstrcnt = strcnt;
|
|
ef->ddbstrtab = ef->strbase;
|
|
|
|
nosyms:
|
|
|
|
#ifdef __arm__
|
|
link_elf_locate_exidx(lf, shdr, hdr->e_shnum);
|
|
#endif
|
|
|
|
error = link_elf_link_common_finish(lf);
|
|
if (error != 0)
|
|
goto out;
|
|
|
|
*result = lf;
|
|
|
|
out:
|
|
VOP_UNLOCK(nd.ni_vp);
|
|
vn_close(nd.ni_vp, FREAD, td->td_ucred, td);
|
|
if (error != 0 && lf != NULL)
|
|
linker_file_unload(lf, LINKER_UNLOAD_FORCE);
|
|
free(shdr, M_LINKER);
|
|
free(firstpage, M_LINKER);
|
|
free(shstrs, M_LINKER);
|
|
|
|
return (error);
|
|
}
|
|
|
|
Elf_Addr
|
|
elf_relocaddr(linker_file_t lf, Elf_Addr x)
|
|
{
|
|
elf_file_t ef;
|
|
|
|
KASSERT(lf->ops->cls == (kobj_class_t)&link_elf_class,
|
|
("elf_relocaddr: unexpected linker file %p", lf));
|
|
|
|
ef = (elf_file_t)lf;
|
|
if (x >= ef->pcpu_start && x < ef->pcpu_stop)
|
|
return ((x - ef->pcpu_start) + ef->pcpu_base);
|
|
#ifdef VIMAGE
|
|
if (x >= ef->vnet_start && x < ef->vnet_stop)
|
|
return ((x - ef->vnet_start) + ef->vnet_base);
|
|
#endif
|
|
return (x);
|
|
}
|
|
|
|
static void
|
|
link_elf_unload_file(linker_file_t file)
|
|
{
|
|
elf_file_t ef = (elf_file_t) file;
|
|
|
|
if (ef->pcpu_base != 0) {
|
|
dpcpu_free((void *)ef->pcpu_base,
|
|
ef->pcpu_stop - ef->pcpu_start);
|
|
elf_set_delete(&set_pcpu_list, ef->pcpu_start);
|
|
}
|
|
#ifdef VIMAGE
|
|
if (ef->vnet_base != 0) {
|
|
vnet_data_free((void *)ef->vnet_base,
|
|
ef->vnet_stop - ef->vnet_start);
|
|
elf_set_delete(&set_vnet_list, ef->vnet_start);
|
|
}
|
|
#endif
|
|
#ifdef GDB
|
|
if (ef->gdb.l_ld != NULL) {
|
|
GDB_STATE(RT_DELETE);
|
|
free((void *)(uintptr_t)ef->gdb.l_name, M_LINKER);
|
|
link_elf_delete_gdb(&ef->gdb);
|
|
GDB_STATE(RT_CONSISTENT);
|
|
}
|
|
#endif
|
|
|
|
/* Notify MD code that a module is being unloaded. */
|
|
elf_cpu_unload_file(file);
|
|
|
|
if (ef->preloaded) {
|
|
link_elf_unload_preload(file);
|
|
return;
|
|
}
|
|
|
|
#ifdef SPARSE_MAPPING
|
|
if (ef->object != NULL) {
|
|
vm_map_remove(kernel_map, (vm_offset_t) ef->address,
|
|
(vm_offset_t) ef->address
|
|
+ (ef->object->size << PAGE_SHIFT));
|
|
}
|
|
#else
|
|
free(ef->address, M_LINKER);
|
|
#endif
|
|
free(ef->symbase, M_LINKER);
|
|
free(ef->strbase, M_LINKER);
|
|
free(ef->ctftab, M_LINKER);
|
|
free(ef->ctfoff, M_LINKER);
|
|
free(ef->typoff, M_LINKER);
|
|
}
|
|
|
|
static void
|
|
link_elf_unload_preload(linker_file_t file)
|
|
{
|
|
|
|
if (file->pathname != NULL)
|
|
preload_delete_name(file->pathname);
|
|
}
|
|
|
|
static const char *
|
|
symbol_name(elf_file_t ef, Elf_Size r_info)
|
|
{
|
|
const Elf_Sym *ref;
|
|
|
|
if (ELF_R_SYM(r_info)) {
|
|
ref = ef->symtab + ELF_R_SYM(r_info);
|
|
return (ef->strtab + ref->st_name);
|
|
}
|
|
return (NULL);
|
|
}
|
|
|
|
static int
|
|
symbol_type(elf_file_t ef, Elf_Size r_info)
|
|
{
|
|
const Elf_Sym *ref;
|
|
|
|
if (ELF_R_SYM(r_info)) {
|
|
ref = ef->symtab + ELF_R_SYM(r_info);
|
|
return (ELF_ST_TYPE(ref->st_info));
|
|
}
|
|
return (STT_NOTYPE);
|
|
}
|
|
|
|
static int
|
|
relocate_file1(elf_file_t ef, elf_lookup_fn lookup, elf_reloc_fn reloc,
|
|
bool ifuncs)
|
|
{
|
|
const Elf_Rel *rel;
|
|
const Elf_Rela *rela;
|
|
const char *symname;
|
|
|
|
#define APPLY_RELOCS(iter, tbl, tblsize, type) do { \
|
|
for ((iter) = (tbl); (iter) != NULL && \
|
|
(iter) < (tbl) + (tblsize) / sizeof(*(iter)); (iter)++) { \
|
|
if ((symbol_type(ef, (iter)->r_info) == \
|
|
STT_GNU_IFUNC || \
|
|
elf_is_ifunc_reloc((iter)->r_info)) != ifuncs) \
|
|
continue; \
|
|
if (reloc(&ef->lf, (Elf_Addr)ef->address, \
|
|
(iter), (type), lookup)) { \
|
|
symname = symbol_name(ef, (iter)->r_info); \
|
|
printf("link_elf: symbol %s undefined\n", \
|
|
symname); \
|
|
return (ENOENT); \
|
|
} \
|
|
} \
|
|
} while (0)
|
|
|
|
APPLY_RELOCS(rel, ef->rel, ef->relsize, ELF_RELOC_REL);
|
|
APPLY_RELOCS(rela, ef->rela, ef->relasize, ELF_RELOC_RELA);
|
|
APPLY_RELOCS(rel, ef->pltrel, ef->pltrelsize, ELF_RELOC_REL);
|
|
APPLY_RELOCS(rela, ef->pltrela, ef->pltrelasize, ELF_RELOC_RELA);
|
|
|
|
#undef APPLY_RELOCS
|
|
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
relocate_file(elf_file_t ef)
|
|
{
|
|
int error;
|
|
|
|
error = relocate_file1(ef, elf_lookup, elf_reloc, false);
|
|
if (error == 0)
|
|
error = relocate_file1(ef, elf_lookup, elf_reloc, true);
|
|
return (error);
|
|
}
|
|
|
|
/*
|
|
* Hash function for symbol table lookup. Don't even think about changing
|
|
* this. It is specified by the System V ABI.
|
|
*/
|
|
static unsigned long
|
|
elf_hash(const char *name)
|
|
{
|
|
const unsigned char *p = (const unsigned char *) name;
|
|
unsigned long h = 0;
|
|
unsigned long g;
|
|
|
|
while (*p != '\0') {
|
|
h = (h << 4) + *p++;
|
|
if ((g = h & 0xf0000000) != 0)
|
|
h ^= g >> 24;
|
|
h &= ~g;
|
|
}
|
|
return (h);
|
|
}
|
|
|
|
static int
|
|
link_elf_lookup_symbol1(linker_file_t lf, const char *name, c_linker_sym_t *sym,
|
|
bool see_local)
|
|
{
|
|
elf_file_t ef = (elf_file_t) lf;
|
|
unsigned long symnum;
|
|
const Elf_Sym* symp;
|
|
const char *strp;
|
|
unsigned long hash;
|
|
|
|
/* If we don't have a hash, bail. */
|
|
if (ef->buckets == NULL || ef->nbuckets == 0) {
|
|
printf("link_elf_lookup_symbol: missing symbol hash table\n");
|
|
return (ENOENT);
|
|
}
|
|
|
|
/* First, search hashed global symbols */
|
|
hash = elf_hash(name);
|
|
symnum = ef->buckets[hash % ef->nbuckets];
|
|
|
|
while (symnum != STN_UNDEF) {
|
|
if (symnum >= ef->nchains) {
|
|
printf("%s: corrupt symbol table\n", __func__);
|
|
return (ENOENT);
|
|
}
|
|
|
|
symp = ef->symtab + symnum;
|
|
if (symp->st_name == 0) {
|
|
printf("%s: corrupt symbol table\n", __func__);
|
|
return (ENOENT);
|
|
}
|
|
|
|
strp = ef->strtab + symp->st_name;
|
|
|
|
if (strcmp(name, strp) == 0) {
|
|
if (symp->st_shndx != SHN_UNDEF ||
|
|
(symp->st_value != 0 &&
|
|
(ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
|
|
ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) {
|
|
if (see_local ||
|
|
ELF_ST_BIND(symp->st_info) != STB_LOCAL) {
|
|
*sym = (c_linker_sym_t) symp;
|
|
return (0);
|
|
}
|
|
}
|
|
return (ENOENT);
|
|
}
|
|
|
|
symnum = ef->chains[symnum];
|
|
}
|
|
|
|
return (ENOENT);
|
|
}
|
|
|
|
static int
|
|
link_elf_lookup_symbol(linker_file_t lf, const char *name, c_linker_sym_t *sym)
|
|
{
|
|
if (link_elf_leak_locals)
|
|
return (link_elf_lookup_debug_symbol(lf, name, sym));
|
|
return (link_elf_lookup_symbol1(lf, name, sym, false));
|
|
}
|
|
|
|
static int
|
|
link_elf_lookup_debug_symbol(linker_file_t lf, const char *name,
|
|
c_linker_sym_t *sym)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
const Elf_Sym* symp;
|
|
const char *strp;
|
|
int i;
|
|
|
|
if (link_elf_lookup_symbol1(lf, name, sym, true) == 0)
|
|
return (0);
|
|
|
|
for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
|
|
strp = ef->ddbstrtab + symp->st_name;
|
|
if (strcmp(name, strp) == 0) {
|
|
if (symp->st_shndx != SHN_UNDEF ||
|
|
(symp->st_value != 0 &&
|
|
(ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
|
|
ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC))) {
|
|
*sym = (c_linker_sym_t) symp;
|
|
return (0);
|
|
}
|
|
return (ENOENT);
|
|
}
|
|
}
|
|
|
|
return (ENOENT);
|
|
}
|
|
|
|
static int
|
|
link_elf_symbol_values1(linker_file_t lf, c_linker_sym_t sym,
|
|
linker_symval_t *symval, bool see_local)
|
|
{
|
|
elf_file_t ef;
|
|
const Elf_Sym *es;
|
|
caddr_t val;
|
|
|
|
ef = (elf_file_t)lf;
|
|
es = (const Elf_Sym *)sym;
|
|
if (es >= ef->symtab && es < ef->symtab + ef->nchains) {
|
|
if (!see_local && ELF_ST_BIND(es->st_info) == STB_LOCAL)
|
|
return (ENOENT);
|
|
symval->name = ef->strtab + es->st_name;
|
|
val = (caddr_t)ef->address + es->st_value;
|
|
if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC)
|
|
val = ((caddr_t (*)(void))val)();
|
|
symval->value = val;
|
|
symval->size = es->st_size;
|
|
return (0);
|
|
}
|
|
return (ENOENT);
|
|
}
|
|
|
|
static int
|
|
link_elf_symbol_values(linker_file_t lf, c_linker_sym_t sym,
|
|
linker_symval_t *symval)
|
|
{
|
|
if (link_elf_leak_locals)
|
|
return (link_elf_debug_symbol_values(lf, sym, symval));
|
|
return (link_elf_symbol_values1(lf, sym, symval, false));
|
|
}
|
|
|
|
static int
|
|
link_elf_debug_symbol_values(linker_file_t lf, c_linker_sym_t sym,
|
|
linker_symval_t *symval)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
const Elf_Sym *es = (const Elf_Sym *)sym;
|
|
caddr_t val;
|
|
|
|
if (link_elf_symbol_values1(lf, sym, symval, true) == 0)
|
|
return (0);
|
|
if (ef->symtab == ef->ddbsymtab)
|
|
return (ENOENT);
|
|
|
|
if (es >= ef->ddbsymtab && es < (ef->ddbsymtab + ef->ddbsymcnt)) {
|
|
symval->name = ef->ddbstrtab + es->st_name;
|
|
val = (caddr_t)ef->address + es->st_value;
|
|
if (ELF_ST_TYPE(es->st_info) == STT_GNU_IFUNC)
|
|
val = ((caddr_t (*)(void))val)();
|
|
symval->value = val;
|
|
symval->size = es->st_size;
|
|
return (0);
|
|
}
|
|
return (ENOENT);
|
|
}
|
|
|
|
static int
|
|
link_elf_search_symbol(linker_file_t lf, caddr_t value,
|
|
c_linker_sym_t *sym, long *diffp)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
u_long off = (uintptr_t)(void *)value;
|
|
u_long diff = off;
|
|
u_long st_value;
|
|
const Elf_Sym *es;
|
|
const Elf_Sym *best = NULL;
|
|
int i;
|
|
|
|
for (i = 0, es = ef->ddbsymtab; i < ef->ddbsymcnt; i++, es++) {
|
|
if (es->st_name == 0)
|
|
continue;
|
|
st_value = es->st_value + (uintptr_t) (void *) ef->address;
|
|
if (off >= st_value) {
|
|
if (off - st_value < diff) {
|
|
diff = off - st_value;
|
|
best = es;
|
|
if (diff == 0)
|
|
break;
|
|
} else if (off - st_value == diff) {
|
|
best = es;
|
|
}
|
|
}
|
|
}
|
|
if (best == NULL)
|
|
*diffp = off;
|
|
else
|
|
*diffp = diff;
|
|
*sym = (c_linker_sym_t) best;
|
|
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* Look up a linker set on an ELF system.
|
|
*/
|
|
static int
|
|
link_elf_lookup_set(linker_file_t lf, const char *name,
|
|
void ***startp, void ***stopp, int *countp)
|
|
{
|
|
c_linker_sym_t sym;
|
|
linker_symval_t symval;
|
|
char *setsym;
|
|
void **start, **stop;
|
|
int len, error = 0, count;
|
|
|
|
len = strlen(name) + sizeof("__start_set_"); /* sizeof includes \0 */
|
|
setsym = malloc(len, M_LINKER, M_WAITOK);
|
|
|
|
/* get address of first entry */
|
|
snprintf(setsym, len, "%s%s", "__start_set_", name);
|
|
error = link_elf_lookup_symbol(lf, setsym, &sym);
|
|
if (error != 0)
|
|
goto out;
|
|
link_elf_symbol_values(lf, sym, &symval);
|
|
if (symval.value == 0) {
|
|
error = ESRCH;
|
|
goto out;
|
|
}
|
|
start = (void **)symval.value;
|
|
|
|
/* get address of last entry */
|
|
snprintf(setsym, len, "%s%s", "__stop_set_", name);
|
|
error = link_elf_lookup_symbol(lf, setsym, &sym);
|
|
if (error != 0)
|
|
goto out;
|
|
link_elf_symbol_values(lf, sym, &symval);
|
|
if (symval.value == 0) {
|
|
error = ESRCH;
|
|
goto out;
|
|
}
|
|
stop = (void **)symval.value;
|
|
|
|
/* and the number of entries */
|
|
count = stop - start;
|
|
|
|
/* and copy out */
|
|
if (startp != NULL)
|
|
*startp = start;
|
|
if (stopp != NULL)
|
|
*stopp = stop;
|
|
if (countp != NULL)
|
|
*countp = count;
|
|
|
|
out:
|
|
free(setsym, M_LINKER);
|
|
return (error);
|
|
}
|
|
|
|
static int
|
|
link_elf_each_function_name(linker_file_t file,
|
|
int (*callback)(const char *, void *), void *opaque)
|
|
{
|
|
elf_file_t ef = (elf_file_t)file;
|
|
const Elf_Sym *symp;
|
|
int i, error;
|
|
|
|
/* Exhaustive search */
|
|
for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
|
|
if (symp->st_value != 0 &&
|
|
(ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
|
|
ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) {
|
|
error = callback(ef->ddbstrtab + symp->st_name, opaque);
|
|
if (error != 0)
|
|
return (error);
|
|
}
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
link_elf_each_function_nameval(linker_file_t file,
|
|
linker_function_nameval_callback_t callback, void *opaque)
|
|
{
|
|
linker_symval_t symval;
|
|
elf_file_t ef = (elf_file_t)file;
|
|
const Elf_Sym *symp;
|
|
int i, error;
|
|
|
|
/* Exhaustive search */
|
|
for (i = 0, symp = ef->ddbsymtab; i < ef->ddbsymcnt; i++, symp++) {
|
|
if (symp->st_value != 0 &&
|
|
(ELF_ST_TYPE(symp->st_info) == STT_FUNC ||
|
|
ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC)) {
|
|
error = link_elf_debug_symbol_values(file,
|
|
(c_linker_sym_t) symp, &symval);
|
|
if (error == 0)
|
|
error = callback(file, i, &symval, opaque);
|
|
if (error != 0)
|
|
return (error);
|
|
}
|
|
}
|
|
return (0);
|
|
}
|
|
|
|
const Elf_Sym *
|
|
elf_get_sym(linker_file_t lf, Elf_Size symidx)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
|
|
if (symidx >= ef->nchains)
|
|
return (NULL);
|
|
return (ef->symtab + symidx);
|
|
}
|
|
|
|
const char *
|
|
elf_get_symname(linker_file_t lf, Elf_Size symidx)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
const Elf_Sym *sym;
|
|
|
|
if (symidx >= ef->nchains)
|
|
return (NULL);
|
|
sym = ef->symtab + symidx;
|
|
return (ef->strtab + sym->st_name);
|
|
}
|
|
|
|
/*
|
|
* Symbol lookup function that can be used when the symbol index is known (ie
|
|
* in relocations). It uses the symbol index instead of doing a fully fledged
|
|
* hash table based lookup when such is valid. For example for local symbols.
|
|
* This is not only more efficient, it's also more correct. It's not always
|
|
* the case that the symbol can be found through the hash table.
|
|
*/
|
|
static int
|
|
elf_lookup(linker_file_t lf, Elf_Size symidx, int deps, Elf_Addr *res)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
const Elf_Sym *sym;
|
|
const char *symbol;
|
|
Elf_Addr addr, start, base;
|
|
|
|
/* Don't even try to lookup the symbol if the index is bogus. */
|
|
if (symidx >= ef->nchains) {
|
|
*res = 0;
|
|
return (EINVAL);
|
|
}
|
|
|
|
sym = ef->symtab + symidx;
|
|
|
|
/*
|
|
* Don't do a full lookup when the symbol is local. It may even
|
|
* fail because it may not be found through the hash table.
|
|
*/
|
|
if (ELF_ST_BIND(sym->st_info) == STB_LOCAL) {
|
|
/* Force lookup failure when we have an insanity. */
|
|
if (sym->st_shndx == SHN_UNDEF || sym->st_value == 0) {
|
|
*res = 0;
|
|
return (EINVAL);
|
|
}
|
|
*res = ((Elf_Addr)ef->address + sym->st_value);
|
|
return (0);
|
|
}
|
|
|
|
/*
|
|
* XXX we can avoid doing a hash table based lookup for global
|
|
* symbols as well. This however is not always valid, so we'll
|
|
* just do it the hard way for now. Performance tweaks can
|
|
* always be added.
|
|
*/
|
|
|
|
symbol = ef->strtab + sym->st_name;
|
|
|
|
/* Force a lookup failure if the symbol name is bogus. */
|
|
if (*symbol == 0) {
|
|
*res = 0;
|
|
return (EINVAL);
|
|
}
|
|
|
|
addr = ((Elf_Addr)linker_file_lookup_symbol(lf, symbol, deps));
|
|
if (addr == 0 && ELF_ST_BIND(sym->st_info) != STB_WEAK) {
|
|
*res = 0;
|
|
return (EINVAL);
|
|
}
|
|
|
|
if (elf_set_find(&set_pcpu_list, addr, &start, &base))
|
|
addr = addr - start + base;
|
|
#ifdef VIMAGE
|
|
else if (elf_set_find(&set_vnet_list, addr, &start, &base))
|
|
addr = addr - start + base;
|
|
#endif
|
|
*res = addr;
|
|
return (0);
|
|
}
|
|
|
|
static void
|
|
link_elf_reloc_local(linker_file_t lf)
|
|
{
|
|
const Elf_Rel *rellim;
|
|
const Elf_Rel *rel;
|
|
const Elf_Rela *relalim;
|
|
const Elf_Rela *rela;
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
|
|
/* Perform relocations without addend if there are any: */
|
|
if ((rel = ef->rel) != NULL) {
|
|
rellim = (const Elf_Rel *)((const char *)ef->rel + ef->relsize);
|
|
while (rel < rellim) {
|
|
elf_reloc_local(lf, (Elf_Addr)ef->address, rel,
|
|
ELF_RELOC_REL, elf_lookup);
|
|
rel++;
|
|
}
|
|
}
|
|
|
|
/* Perform relocations with addend if there are any: */
|
|
if ((rela = ef->rela) != NULL) {
|
|
relalim = (const Elf_Rela *)
|
|
((const char *)ef->rela + ef->relasize);
|
|
while (rela < relalim) {
|
|
elf_reloc_local(lf, (Elf_Addr)ef->address, rela,
|
|
ELF_RELOC_RELA, elf_lookup);
|
|
rela++;
|
|
}
|
|
}
|
|
}
|
|
|
|
static long
|
|
link_elf_symtab_get(linker_file_t lf, const Elf_Sym **symtab)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
|
|
*symtab = ef->ddbsymtab;
|
|
|
|
if (*symtab == NULL)
|
|
return (0);
|
|
|
|
return (ef->ddbsymcnt);
|
|
}
|
|
|
|
static long
|
|
link_elf_strtab_get(linker_file_t lf, caddr_t *strtab)
|
|
{
|
|
elf_file_t ef = (elf_file_t)lf;
|
|
|
|
*strtab = ef->ddbstrtab;
|
|
|
|
if (*strtab == NULL)
|
|
return (0);
|
|
|
|
return (ef->ddbstrcnt);
|
|
}
|
|
|
|
#if defined(__i386__) || defined(__amd64__) || defined(__aarch64__) || defined(__powerpc__)
|
|
/*
|
|
* Use this lookup routine when performing relocations early during boot.
|
|
* The generic lookup routine depends on kobj, which is not initialized
|
|
* at that point.
|
|
*/
|
|
static int
|
|
elf_lookup_ifunc(linker_file_t lf, Elf_Size symidx, int deps __unused,
|
|
Elf_Addr *res)
|
|
{
|
|
elf_file_t ef;
|
|
const Elf_Sym *symp;
|
|
caddr_t val;
|
|
|
|
ef = (elf_file_t)lf;
|
|
symp = ef->symtab + symidx;
|
|
if (ELF_ST_TYPE(symp->st_info) == STT_GNU_IFUNC) {
|
|
val = (caddr_t)ef->address + symp->st_value;
|
|
*res = ((Elf_Addr (*)(void))val)();
|
|
return (0);
|
|
}
|
|
return (ENOENT);
|
|
}
|
|
|
|
void
|
|
link_elf_ireloc(caddr_t kmdp)
|
|
{
|
|
struct elf_file eff;
|
|
elf_file_t ef;
|
|
|
|
ef = &eff;
|
|
|
|
bzero_early(ef, sizeof(*ef));
|
|
|
|
ef->modptr = kmdp;
|
|
ef->dynamic = (Elf_Dyn *)&_DYNAMIC;
|
|
|
|
#ifdef RELOCATABLE_KERNEL
|
|
ef->address = (caddr_t) (__startkernel - KERNBASE);
|
|
#else
|
|
ef->address = 0;
|
|
#endif
|
|
parse_dynamic(ef);
|
|
|
|
link_elf_preload_parse_symbols(ef);
|
|
relocate_file1(ef, elf_lookup_ifunc, elf_reloc, true);
|
|
}
|
|
|
|
#if defined(__aarch64__) || defined(__amd64__)
|
|
void
|
|
link_elf_late_ireloc(void)
|
|
{
|
|
elf_file_t ef;
|
|
|
|
KASSERT(linker_kernel_file != NULL,
|
|
("link_elf_late_ireloc: No kernel linker file found"));
|
|
ef = (elf_file_t)linker_kernel_file;
|
|
|
|
relocate_file1(ef, elf_lookup_ifunc, elf_reloc_late, true);
|
|
}
|
|
#endif
|
|
#endif
|