generic-library/bionic
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Execute .preinit_array before any shared object initialization functions.

Browse Source 
This change makes linker handling of .preinit_array compliant with the
System V ABI:

"These [pre-initialization] functions are executed after the dynamic linker has
built the process image and performed relocations but before any shared object
initialization functions."
http://www.sco.com/developers/gabi/latest/ch5.dynamic.html#init_fini

Change-Id: Iebfee22bb1ebe1d7c7e69cb4686e4ebae0dfc4bb
This commit is contained in:
Evgeniy Stepanov 2011-12-21 13:03:54 +04:00
parent 334379dada
commit e83c56dfbb
4 changed files with 28 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
linker/README.TXT
View File

@ -87,6 +87,7 @@ section:
present in executables, not shared libraries, which contains
a list of functions that need to be called before any other
initialization function (i.e. DT_INIT and/or DT_INIT_ARRAY)
in the executable or any of its libraries.
Note: this is generally stored in a .preinit_array section

1
linker/dlfcn.c
View File

@ -60,6 +60,7 @@ void *dlopen(const char *filename, int flag)
if (unlikely(ret == NULL)) {
set_dlerror(DL_ERR_CANNOT_LOAD_LIBRARY);
} else {
call_constructors_recursive(ret);
ret->refcount++;
}
pthread_mutex_unlock(&dl_lock);

26
linker/linker.c
View File

@ -1617,8 +1617,11 @@ static void call_array(unsigned *ctor, int count, int reverse)
}
}
static void call_constructors(soinfo *si)
void call_constructors_recursive(soinfo *si)
{
if (si->constructors_called)
return;
if (si->flags & FLAG_EXE) {
TRACE("[ %5d Calling preinit_array @ 0x%08x [%d] for '%s' ]\n",
pid, (unsigned)si->preinit_array, si->preinit_array_count,
@ -1633,6 +1636,21 @@ static void call_constructors(soinfo *si)
}
}
if (si->dynamic) {
unsigned *d;
for(d = si->dynamic; *d; d += 2) {
if(d[0] == DT_NEEDED){
soinfo* lsi = (soinfo *)d[1];
if (!validate_soinfo(lsi)) {
DL_ERR("%5d bad DT_NEEDED pointer in %s",
pid, si->name);
} else {
call_constructors_recursive(lsi);
}
}
}
}
if (si->init_func) {
TRACE("[ %5d Calling init_func @ 0x%08x for '%s' ]\n", pid,
(unsigned)si->init_func, si->name);
@ -1646,8 +1664,9 @@ static void call_constructors(soinfo *si)
call_array(si->init_array, si->init_array_count, 0);
TRACE("[ %5d Done calling init_array for '%s' ]\n", pid, si->name);
}
}
si->constructors_called = 1;
}
static void call_destructors(soinfo *si)
{
@ -2046,7 +2065,6 @@ static int link_image(soinfo *si, unsigned wr_offset)
if (program_is_setuid)
nullify_closed_stdio ();
notify_gdb_of_load(si);
call_constructors(si);
return 0;
fail:
@ -2251,6 +2269,8 @@ static unsigned __linker_init_post_relocation(unsigned **elfdata)
exit(-1);
}
call_constructors_recursive(si);
#if ALLOW_SYMBOLS_FROM_MAIN
/* Set somain after we've loaded all the libraries in order to prevent
* linking of symbols back to the main image, which is not set up at that

3
linker/linker.h
View File

@ -149,6 +149,8 @@ struct soinfo
unsigned refcount;
struct link_map linkmap;
int constructors_called;
};
@ -217,6 +219,7 @@ Elf32_Sym *lookup(const char *name, soinfo **found, soinfo *start);
soinfo *find_containing_library(const void *addr);
Elf32_Sym *find_containing_symbol(const void *addr, soinfo *si);
const char *linker_get_error(void);
void call_constructors_recursive(soinfo *si);
#ifdef ANDROID_ARM_LINKER
typedef long unsigned int *_Unwind_Ptr;