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pie: piegen -- Slightly rework the building procedure

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- Move relocs application into a separate file which get
   compiled as a regular C file in criu (pie/pie-relocs.[ch])
 - Move types used by piegen into pie/piegen/uapi/types.h

Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
This commit is contained in:
Cyrill Gorcunov
2015-06-05 00:04:12 +03:00
committed by Pavel Emelyanov
parent ac187856c4
commit f03a4672ce
10 changed files with 96 additions and 55 deletions
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1
Makefile.crtools
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@@ -72,6 +72,7 @@ obj-y += cr-service.o
obj-y += sd-daemon.o obj-y += sd-daemon.o
obj-y += plugin.o obj-y += plugin.o
obj-y += cr-errno.o obj-y += cr-errno.o
obj-y += pie/pie-relocs.o
ifneq ($(MAKECMDGOALS),clean) ifneq ($(MAKECMDGOALS),clean)
incdeps := y incdeps := y

7
cr-restore.c
View File

@@ -91,6 +91,8 @@
#include "cr-errno.h" #include "cr-errno.h"
#include "pie/pie-relocs.h"
#ifndef arch_export_restore_thread #ifndef arch_export_restore_thread
#define arch_export_restore_thread __export_restore_thread #define arch_export_restore_thread __export_restore_thread
#endif #endif
@@ -2392,10 +2394,9 @@ static int remap_restorer_blob(void *addr)
return -1; return -1;
} }
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_32) elf_relocs_apply(addr, addr, sizeof(restorer_blob),
elf_apply_relocs(addr, addr, sizeof(restorer_blob),
elf_relocs, ARRAY_SIZE(elf_relocs)); elf_relocs, ARRAY_SIZE(elf_relocs));
#endif
return 0; return 0;
} }

5
parasite-syscall.c
View File

@@ -37,6 +37,7 @@
#include "asm/parasite-syscall.h" #include "asm/parasite-syscall.h"
#include "asm/dump.h" #include "asm/dump.h"
#include "asm/restorer.h" #include "asm/restorer.h"
#include "pie/pie-relocs.h"
#if defined(CONFIG_X86_32) || defined(CONFIG_X86_64) #if defined(CONFIG_X86_32) || defined(CONFIG_X86_64)
# define parasite_size (round_up(sizeof(parasite_blob) + nr_gotpcrel * sizeof(long), PAGE_SIZE)) # define parasite_size (round_up(sizeof(parasite_blob) + nr_gotpcrel * sizeof(long), PAGE_SIZE))
@@ -1223,10 +1224,8 @@ struct parasite_ctl *parasite_infect_seized(pid_t pid, struct pstree_item *item,
pr_info("Putting parasite blob into %p->%p\n", ctl->local_map, ctl->remote_map); pr_info("Putting parasite blob into %p->%p\n", ctl->local_map, ctl->remote_map);
memcpy(ctl->local_map, parasite_blob, sizeof(parasite_blob)); memcpy(ctl->local_map, parasite_blob, sizeof(parasite_blob));
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_32) elf_relocs_apply(ctl->local_map, ctl->remote_map, sizeof(parasite_blob),
elf_apply_relocs(ctl->local_map, ctl->remote_map, sizeof(parasite_blob),
elf_relocs, ARRAY_SIZE(elf_relocs)); elf_relocs, ARRAY_SIZE(elf_relocs));
#endif
/* Setup the rest of a control block */ /* Setup the rest of a control block */
ctl->parasite_ip = (unsigned long)parasite_sym(ctl->remote_map, __export_parasite_head_start); ctl->parasite_ip = (unsigned long)parasite_sym(ctl->remote_map, __export_parasite_head_start);

2
pie/Makefile
View File

@@ -34,7 +34,7 @@ restorer-libs-e += $(SYSCALL-LIB)
# applications, which is not the target of the # applications, which is not the target of the
# project. # project.
# #
CFLAGS := $(filter-out -pg,$(CFLAGS)) CFLAGS := $(filter-out -pg,$(CFLAGS)) -iquote pie/piegen
ifneq ($(filter-out i386 ia32, $(ARCH)),) ifneq ($(filter-out i386 ia32, $(ARCH)),)
cflags-y += -DCR_NOGLIBC -fpie -Wa,--noexecstack -fno-stack-protector cflags-y += -DCR_NOGLIBC -fpie -Wa,--noexecstack -fno-stack-protector

47
pie/pie-relocs.c Normal file
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@@ -0,0 +1,47 @@
#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <unistd.h>
#include <stdint.h>
#include <string.h>
#include <fcntl.h>
#include <elf.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>
#include "asm-generic/int.h"
#include "compiler.h"
#include "piegen/uapi/types.h"
#include "bug.h"
__maybe_unused void elf_relocs_apply(void *mem, void *vbase, size_t size, elf_reloc_t *elf_relocs, size_t nr_relocs)
{
size_t i, j;
for (i = 0, j = 0; i < nr_relocs; i++) {
if (elf_relocs[i].type & PIEGEN_TYPE_LONG) {
long *where = mem + elf_relocs[i].offset;
long *p = mem + size;
if (elf_relocs[i].type & PIEGEN_TYPE_GOTPCREL) {
int *value = (int *)where;
int rel;
p[j] = (long)vbase + elf_relocs[i].value;
rel = (unsigned)((void *)&p[j] - (void *)mem) - elf_relocs[i].offset + elf_relocs[i].addend;
*value = rel;
j++;
} else
*where = elf_relocs[i].value + elf_relocs[i].addend + (unsigned long)vbase;
} else if (elf_relocs[i].type & PIEGEN_TYPE_INT) {
int *where = (mem + elf_relocs[i].offset);
*where = elf_relocs[i].value + elf_relocs[i].addend + (unsigned long)vbase;
} else
BUG();
}
}

15
pie/pie-relocs.h Normal file
View File

@@ -0,0 +1,15 @@
#ifndef __PIE_RELOCS_H__
#define __PIE_RELOCS_H__
#include "piegen/uapi/types.h"
#include "compiler.h"
#include "config.h"
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_32)
extern __maybe_unused void elf_relocs_apply(void *mem, void *vbase, size_t size, elf_reloc_t *elf_relocs, size_t nr_relocs);
#else
static always_inline void elf_relocs_apply(void *mem, void *vbase, size_t size, elf_reloc_t *elf_relocs, size_t nr_relocs) { }
#endif
#endif /* __PIE_RELOCS_H__ */

51
pie/piegen/elf.c
View File

@@ -126,6 +126,8 @@ int handle_elf(const piegen_opt_t *opts, void *mem, size_t size)
} }
pr_out("/* Autogenerated from %s */\n", opts->input_filename); pr_out("/* Autogenerated from %s */\n", opts->input_filename);
pr_out("#include \"piegen/uapi/types.h\"\n");
for (i = 0; i < symtab_hdr->sh_size / symtab_hdr->sh_entsize; i++) { for (i = 0; i < symtab_hdr->sh_size / symtab_hdr->sh_entsize; i++) {
Sym_t *sym = &symbols[i]; Sym_t *sym = &symbols[i];
const char *name; const char *name;
@@ -155,13 +157,7 @@ int handle_elf(const piegen_opt_t *opts, void *mem, size_t size)
} }
} }
pr_out("typedef struct {\n" pr_out("static __maybe_unused elf_reloc_t %s[] = {\n", opts->var_name);
" unsigned int offset;\n"
" unsigned int type;\n"
" long addend;\n"
" long value;\n"
"} %s;\nstatic __maybe_unused %s %s[] = {\n",
opts->type_name, opts->type_name, opts->var_name);
pr_debug("Relocations\n------------\n"); pr_debug("Relocations\n------------\n");
for (i = 0; i < hdr->e_shnum; i++) { for (i = 0; i < hdr->e_shnum; i++) {
@@ -232,16 +228,17 @@ int handle_elf(const piegen_opt_t *opts, void *mem, size_t size)
value64 = (s64)sh_src->sh_offset + (s64)sym->st_value; value64 = (s64)sh_src->sh_offset + (s64)sym->st_value;
switch (ELF_R_TYPE(r->rel.r_info)) { switch (ELF_R_TYPE(r->rel.r_info)) {
#ifdef ELF_X86_64 #ifdef ELF_X86_64
case R_X86_64_32: /* Symbol + Addend (4 bytes) */ case R_X86_64_32: /* Symbol + Addend (4 bytes) */
pr_debug("\t\t\t\tR_X86_64_32 at 0x%-4lx val 0x%x\n", place, value32); pr_debug("\t\t\t\tR_X86_64_32 at 0x%-4lx val 0x%x\n", place, value32);
pr_out(" { .offset = 0x%-8x, .type = 0, " pr_out(" { .offset = 0x%-8x, .type = PIEGEN_TYPE_INT, "
".addend = %-8d, .value = 0x%-16x, }, /* R_X86_64_32 */\n", ".addend = %-8d, .value = 0x%-16x, }, /* R_X86_64_32 */\n",
(unsigned int)place, addend32, value32); (unsigned int)place, addend32, value32);
break; break;
case R_X86_64_64: /* Symbol + Addend (8 bytes) */ case R_X86_64_64: /* Symbol + Addend (8 bytes) */
pr_debug("\t\t\t\tR_X86_64_64 at 0x%-4lx val 0x%lx\n", place, value64); pr_debug("\t\t\t\tR_X86_64_64 at 0x%-4lx val 0x%lx\n", place, value64);
pr_out(" { .offset = 0x%-8x, .type = 1, " pr_out(" { .offset = 0x%-8x, .type = PIEGEN_TYPE_LONG, "
".addend = %-8ld, .value = 0x%-16lx, }, /* R_X86_64_64 */\n", ".addend = %-8ld, .value = 0x%-16lx, }, /* R_X86_64_64 */\n",
(unsigned int)place, (long)addend64, (long)value64); (unsigned int)place, (long)addend64, (long)value64);
break; break;
@@ -261,16 +258,17 @@ int handle_elf(const piegen_opt_t *opts, void *mem, size_t size)
break; break;
case R_X86_64_GOTPCREL: /* SymbolOffsetInGot + GOT + Addend - Place (4 bytes) */ case R_X86_64_GOTPCREL: /* SymbolOffsetInGot + GOT + Addend - Place (4 bytes) */
pr_debug("\t\t\t\tR_X86_64_GOTPCREL at 0x%-4lx val 0x%x\n", place, value32); pr_debug("\t\t\t\tR_X86_64_GOTPCREL at 0x%-4lx val 0x%x\n", place, value32);
pr_out(" { .offset = 0x%-8x, .type = 3, " pr_out(" { .offset = 0x%-8x, .type = PIEGEN_TYPE_LONG | PIEGEN_TYPE_GOTPCREL, "
".addend = %-8d, .value = 0x%-16x, }, /* R_X86_64_GOTPCREL */\n", ".addend = %-8d, .value = 0x%-16x, }, /* R_X86_64_GOTPCREL */\n",
(unsigned int)place, addend32, value32); (unsigned int)place, addend32, value32);
nr_gotpcrel++; nr_gotpcrel++;
break; break;
#endif #endif
#ifdef ELF_X86_32 #ifdef ELF_X86_32
case R_386_32: /* Symbol + Addend */ case R_386_32: /* Symbol + Addend */
pr_debug("\t\t\t\tR_386_32 at 0x%-4lx val 0x%x\n", place, value32 + addend32); pr_debug("\t\t\t\tR_386_32 at 0x%-4lx val 0x%x\n", place, value32 + addend32);
pr_out(" { .offset = 0x%-8x, .type = 0, " pr_out(" { .offset = 0x%-8x, .type = PIEGEN_TYPE_INT, "
".addend = %-4d, .value = 0x%x, },\n", ".addend = %-4d, .value = 0x%x, },\n",
(unsigned int)place, addend32, value32); (unsigned int)place, addend32, value32);
break; break;
@@ -282,6 +280,7 @@ int handle_elf(const piegen_opt_t *opts, void *mem, size_t size)
*((s32 *)where) = value32 + addend32 - place; *((s32 *)where) = value32 + addend32 - place;
break; break;
#endif #endif
default: default:
pr_err("Unsupported relocation\n"); pr_err("Unsupported relocation\n");
goto err; goto err;
@@ -302,36 +301,6 @@ int handle_elf(const piegen_opt_t *opts, void *mem, size_t size)
} }
pr_out("};\n"); pr_out("};\n");
#if defined(CONFIG_X86_64) || defined(CONFIG_X86_32)
pr_out(
"static __maybe_unused void elf_apply_relocs(void *mem, void *vbase, size_t size, %s *elf_relocs, size_t nr_relocs)\n"
"{\n"
" size_t i, j;\n"
"\n"
" for (i = 0, j = 0; i < nr_relocs; i++) {\n"
" if (elf_relocs[i].type) {\n"
" long *where = mem + elf_relocs[i].offset;\n"
" long *p = mem + size;\n"
"\n"
" if (elf_relocs[i].type & 2) {\n"
" int *value = (int *)where;\n"
" int rel;\n"
"\n"
" p[j] = (long)vbase + elf_relocs[i].value;\n"
" rel = (unsigned)((void *)&p[j] - (void *)mem) - elf_relocs[i].offset + elf_relocs[i].addend;\n"
"\n"
" *value = rel;\n"
" j++;\n"
" } else\n"
" *where = elf_relocs[i].value + elf_relocs[i].addend + (unsigned long)vbase;\n"
" } else {\n"
" int *where = (mem + elf_relocs[i].offset);\n"
" *where = elf_relocs[i].value + elf_relocs[i].addend + (unsigned long)vbase;\n"
" }\n"
" }\n"
"}\n", opts->type_name);
#endif
err: err:
free(sec_hdrs); free(sec_hdrs);
return -1; return -1;

7
pie/piegen/main.c
View File

@@ -20,7 +20,6 @@
piegen_opt_t opts = { piegen_opt_t opts = {
.input_filename = "file.o", .input_filename = "file.o",
.stream_name = "stream", .stream_name = "stream",
.type_name = "elf_reloc_t",
.prefix_name = "__", .prefix_name = "__",
.var_name = "elf_relocs", .var_name = "elf_relocs",
.nrgotpcrel_name = "nr_gotpcrel", .nrgotpcrel_name = "nr_gotpcrel",
@@ -59,11 +58,10 @@ int main(int argc, char *argv[])
void *mem; void *mem;
int fd; int fd;
static const char short_opts[] = "f:s:t:p:v:h"; static const char short_opts[] = "f:s:p:v:h";
static struct option long_opts[] = { static struct option long_opts[] = {
{ "file", required_argument, 0, 'f' }, { "file", required_argument, 0, 'f' },
{ "stream", required_argument, 0, 's' }, { "stream", required_argument, 0, 's' },
{ "type", required_argument, 0, 't' },
{ "sym-prefix", required_argument, 0, 'p' }, { "sym-prefix", required_argument, 0, 'p' },
{ "variable", required_argument, 0, 'v' }, { "variable", required_argument, 0, 'v' },
{ "help", required_argument, 0, 'h' }, { "help", required_argument, 0, 'h' },
@@ -88,9 +86,6 @@ int main(int argc, char *argv[])
case 'p': case 'p':
opts.prefix_name = optarg; opts.prefix_name = optarg;
break; break;
case 't':
opts.type_name = optarg;
break;
case 'v': case 'v':
opts.var_name = optarg; opts.var_name = optarg;
break; break;

1
pie/piegen/piegen.h
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@@ -7,7 +7,6 @@
typedef struct { typedef struct {
char *input_filename; char *input_filename;
char *stream_name; char *stream_name;
char *type_name;
char *prefix_name; char *prefix_name;
char *var_name; char *var_name;
char *nrgotpcrel_name; char *nrgotpcrel_name;

15
pie/piegen/uapi/types.h Normal file
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@@ -0,0 +1,15 @@
#ifndef __PIEGEN_TYPES_H__
#define __PIEGEN_TYPES_H__
#define PIEGEN_TYPE_INT (1u << 0)
#define PIEGEN_TYPE_LONG (1u << 1)
#define PIEGEN_TYPE_GOTPCREL (1u << 2)
typedef struct {
unsigned int offset;
unsigned int type;
long addend;
long value;
} elf_reloc_t;
#endif /* __PIEGEN_TYPES_H__ */