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Fix kldxref on sparc64 by allowing non-trivial relocations to be performed

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on variables read out of raw kld files.  Unlike other platforms the value
will be in an Elf_Rela, not in the data section of the elf file.

Submitted by:	Hartmut Brandt <brandt@fokus.gmd.de>
PR:		46730
Tested on:	alpha (obrien), i386, sparc64
This commit is contained in:
Jake Burkholder 2003-01-21 03:51:53 +00:00
parent ec35c2af68
commit 1eed250ad8
6 changed files with 238 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

6
usr.sbin/kldxref/Makefile
View File

@ -5,4 +5,10 @@ SRCS= kldxref.c ef.c
WARNS?= 2
MAN= kldxref.8
.if exists(ef_${MACHINE_ARCH}.c)
SRCS+= ef_${MACHINE_ARCH}.c
.else
SRCS+= ef_nop.c
.endif
.include <bsd.prog.mk>

120
usr.sbin/kldxref/ef.c
View File

@ -151,7 +151,16 @@ ef_parse_dynamic(elf_file_t ef)
Elf_Hashelt hashhdr[2];
/* int plttype = DT_REL;*/
int error;
Elf_Off rel_off;
Elf_Off rela_off;
int rel_sz;
int rela_sz;
int rel_entry;
int rela_entry;
rel_off = rela_off = 0;
rel_sz = rela_sz = 0;
rel_entry = rela_entry = 0;
for (dp = ef->ef_dyn; dp->d_tag != DT_NULL; dp++) {
switch (dp->d_tag) {
case DT_HASH:
@ -187,6 +196,36 @@ ef_parse_dynamic(elf_file_t ef)
if (dp->d_un.d_val != sizeof(Elf_Sym))
return EFTYPE;
break;
case DT_REL:
if (rel_off != 0)
warnx("second DT_REL entry ignored");
rel_off = dp->d_un.d_ptr;
break;
case DT_RELSZ:
if (rel_sz != 0)
warnx("second DT_RELSZ entry ignored");
rel_sz = dp->d_un.d_val;
break;
case DT_RELENT:
if (rel_entry != 0)
warnx("second DT_RELENT entry ignored");
rel_entry = dp->d_un.d_val;
break;
case DT_RELA:
if (rela_off != 0)
warnx("second DT_RELA entry ignored");
rela_off = dp->d_un.d_ptr;
break;
case DT_RELASZ:
if (rela_sz != 0)
warnx("second DT_RELASZ entry ignored");
rela_sz = dp->d_un.d_val;
break;
case DT_RELAENT:
if (rela_entry != 0)
warnx("second DT_RELAENT entry ignored");
rela_entry = dp->d_un.d_val;
break;
}
}
if (ef->ef_symoff == 0) {
@ -210,6 +249,56 @@ ef_parse_dynamic(elf_file_t ef)
warnx("can't load .dynstr section");
return EIO;
}
if (rel_off != 0) {
if (rel_entry == 0) {
warnx("%s: no DT_RELENT for DT_REL", ef->ef_name);
return (EFTYPE);
}
if (rel_entry != sizeof(Elf_Rel)) {
warnx("%s: inconsistent DT_RELENT value",
ef->ef_name);
return (EFTYPE);
}
if (rel_sz % rel_entry != 0) {
warnx("%s: inconsistent values for DT_RELSZ and "
"DT_RELENT", ef->ef_name);
return (EFTYPE);
}
if (ef_read_entry(ef, ef_get_offset(ef, rel_off), rel_sz,
(void **)&ef->ef_rel) != 0) {
warnx("%s: cannot load DT_REL section", ef->ef_name);
return (EIO);
}
ef->ef_relsz = rel_sz / rel_entry;
if (ef->ef_verbose)
warnx("%s: %d REL entries", ef->ef_name,
ef->ef_relsz);
}
if (rela_off != 0) {
if (rela_entry == 0) {
warnx("%s: no DT_RELAENT for DT_RELA", ef->ef_name);
return (EFTYPE);
}
if (rela_entry != sizeof(Elf_Rela)) {
warnx("%s: inconsistent DT_RELAENT value",
ef->ef_name);
return (EFTYPE);
}
if (rela_sz % rela_entry != 0) {
warnx("%s: inconsistent values for DT_RELASZ and "
"DT_RELAENT", ef->ef_name);
return (EFTYPE);
}
if (ef_read_entry(ef, ef_get_offset(ef, rela_off), rela_sz,
(void **)&ef->ef_rela) != 0) {
warnx("%s: cannot load DT_RELA section", ef->ef_name);
return (EIO);
}
ef->ef_relasz = rela_sz / rela_entry;
if (ef->ef_verbose)
warnx("%s: %d RELA entries", ef->ef_name,
ef->ef_relasz);
}
return 0;
}
@ -258,6 +347,23 @@ ef_seg_read(elf_file_t ef, Elf_Off offset, size_t len, void*dest)
return ef_read(ef, ofs, len, dest);
}
int
ef_seg_read_rel(elf_file_t ef, Elf_Off offset, size_t len, void*dest)
{
u_long ofs = ef_get_offset(ef, offset);
int error;
if (ofs == 0) {
if (ef->ef_verbose)
warnx("ef_seg_read(%s): zero offset (%lx:%ld)",
ef->ef_name, (long)offset, ofs);
return EFAULT;
}
if ((error = ef_read(ef, ofs, len, dest)) != 0)
return (error);
return (ef_reloc(ef, offset, len, dest));
}
int
ef_seg_read_entry(elf_file_t ef, Elf_Off offset, size_t len, void**ptr)
{
@ -272,6 +378,20 @@ ef_seg_read_entry(elf_file_t ef, Elf_Off offset, size_t len, void**ptr)
return error;
}
int
ef_seg_read_entry_rel(elf_file_t ef, Elf_Off offset, size_t len, void**ptr)
{
int error;
*ptr = malloc(len);
if (*ptr == NULL)
return ENOMEM;
error = ef_seg_read_rel(ef, offset, len, *ptr);
if (error)
free(*ptr);
return error;
}
int
ef_open(const char *filename, elf_file_t ef, int verbose)
{

7
usr.sbin/kldxref/ef.h
View File

@ -28,6 +28,10 @@ typedef struct elf_file {
int ef_nsegs;
Elf_Phdr * ef_segs[2];
int ef_verbose;
Elf_Rel * ef_rel; /* relocation table */
int ef_relsz; /* number of entries */
Elf_Rela * ef_rela; /* relocation table */
int ef_relasz; /* number of entries */
} *elf_file_t;
__BEGIN_DECLS
@ -35,8 +39,11 @@ int ef_open(const char *, elf_file_t, int);
int ef_close(elf_file_t ef);
int ef_read(elf_file_t ef, Elf_Off offset, size_t len, void* dest);
int ef_read_entry(elf_file_t ef, Elf_Off offset, size_t len, void **ptr);
int ef_reloc(elf_file_t ef, Elf_Off offset, size_t len, void *dest);
int ef_seg_read(elf_file_t ef, Elf_Off offset, size_t len, void *dest);
int ef_seg_read_rel(elf_file_t ef, Elf_Off offset, size_t len, void *dest);
int ef_seg_read_entry(elf_file_t ef, Elf_Off offset, size_t len, void**ptr);
int ef_seg_read_entry_rel(elf_file_t ef, Elf_Off offset, size_t len, void**ptr);
int ef_lookup_symbol(elf_file_t ef, const char* name, Elf_Sym** sym);
__END_DECLS

39
usr.sbin/kldxref/ef_nop.c Normal file
View File

@ -0,0 +1,39 @@
/*-
* Copyright (c) 2003 Jake Burkholder.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <machine/elf.h>
#include "ef.h"
int
ef_reloc(elf_file_t ef, Elf_Off offset, size_t len, void *dest)
{
return (0);
}

63
usr.sbin/kldxref/ef_sparc64.c Normal file
View File

@ -0,0 +1,63 @@
/*-
* Copyright (c) 2003 Jake Burkholder.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#include <sys/types.h>
#include <machine/elf.h>
#include <err.h>
#include <string.h>
#include "ef.h"
/*
* Apply relocations to the values we got from the file.
*/
int
ef_reloc(elf_file_t ef, Elf_Off offset, size_t len, void *dest)
{
const Elf_Rela *a;
Elf_Word w;
for (a = ef->ef_rela; a < &ef->ef_rela[ef->ef_relasz]; a++) {
if (a->r_offset >= offset && a->r_offset < offset + len) {
switch (ELF_R_TYPE(a->r_info)) {
case R_SPARC_RELATIVE:
/* load address is 0 */
w = a->r_addend;
memcpy((u_char *)dest + (a->r_offset - offset),
&w, sizeof(w));
break;
default:
warnx("unhandled relocation type %u",
ELF_R_TYPE(a->r_info));
break;
}
}
}
return (0);
}

5
usr.sbin/kldxref/kldxref.c
View File

@ -229,10 +229,11 @@ read_kld(char *filename, char *kldname)
check(ef_lookup_symbol(&ef, "__stop_set_" MDT_SETNAME, &sym));
finish = sym->st_value;
entries = (finish - start) / sizeof(void *);
check(ef_seg_read_entry(&ef, start, sizeof(*p) * entries, (void**)&p));
check(ef_seg_read_entry_rel(&ef, start, sizeof(*p) * entries,
(void**)&p));
orgp = p;
while(entries--) {
check(ef_seg_read(&ef, (Elf_Off)*p, sizeof(md), &md));
check(ef_seg_read_rel(&ef, (Elf_Off)*p, sizeof(md), &md));
p++;
check(ef_seg_read(&ef, (Elf_Off)md.md_cval, sizeof(cval), cval));
cval[MAXMODNAME] = '\0';