dynlink.c 80.4 KB
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#define _GNU_SOURCE
#define SYSCALL_NO_TLS 1
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#include "dynlink.h"

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#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <stddef.h>
#include <string.h>
#include <unistd.h>
#include <stdint.h>
#include <elf.h>
#include <sys/mman.h>
#include <limits.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <errno.h>
#include <link.h>
#include <setjmp.h>
#include <pthread.h>
#include <ctype.h>
#include <dlfcn.h>
#include <semaphore.h>
#include <sys/membarrier.h>
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#include "ld_log.h"
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#include "libc.h"
#include "malloc_impl.h"
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#include "namespace.h"
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#include "ns_config.h"
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#include "pthread_impl.h"
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static void error(const char *, ...);

#define MAXP2(a,b) (-(-(a)&-(b)))
#define ALIGN(x,y) ((x)+(y)-1 & -(y))

#define container_of(p,t,m) ((t*)((char *)(p)-offsetof(t,m)))
#define countof(a) ((sizeof (a))/(sizeof (a)[0]))
#define DSO_FLAGS_NODELETE 0x1

struct debug {
	int ver;
	void *head;
	void (*bp)(void);
	int state;
	void *base;
};

struct td_index {
	size_t args[2];
	struct td_index *next;
};

struct dso {
#if DL_FDPIC
	struct fdpic_loadmap *loadmap;
#else
	unsigned char *base;
#endif
	char *name;
	size_t *dynv;
	struct dso *next, *prev;
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	/* add namespace */
	ns_t *namespace;
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	/* mark the dso status */
	unsigned int flags;

	Phdr *phdr;
	int phnum;
	size_t phentsize;
	Sym *syms;
	Elf_Symndx *hashtab;
	uint32_t *ghashtab;
	int16_t *versym;
	char *strings;
	struct dso *syms_next, *lazy_next;
	size_t *lazy, lazy_cnt;
	unsigned char *map;
	size_t map_len;
	dev_t dev;
	ino_t ino;
	char relocated;
	char constructed;
	char kernel_mapped;
	char mark;
	char bfs_built;
	char runtime_loaded;
	char by_dlopen;
	struct dso **deps, *needed_by;
	size_t ndeps_direct;
	size_t next_dep;
	int ctor_visitor;
	int nr_dlopen;
	char *rpath_orig, *rpath;
	struct tls_module tls;
	size_t tls_id;
	size_t relro_start, relro_end;
	uintptr_t *new_dtv;
	unsigned char *new_tls;
	struct td_index *td_index;
	struct dso *fini_next;
	char *shortname;
#if DL_FDPIC
	unsigned char *base;
#else
	struct fdpic_loadmap *loadmap;
#endif
	struct funcdesc {
		void *addr;
		size_t *got;
	} *funcdescs;
	size_t *got;
	char buf[];
};

struct symdef {
	Sym *sym;
	struct dso *dso;
};

typedef void (*stage3_func)(size_t *, size_t *);

static struct builtin_tls {
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	char c[8];
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	struct pthread pt;
	void *space[16];
} builtin_tls[1];
#define MIN_TLS_ALIGN offsetof(struct builtin_tls, pt)

#define ADDEND_LIMIT 4096
static size_t *saved_addends, *apply_addends_to;
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static bool g_is_asan;
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static struct dso ldso;
static struct dso *head, *tail, *fini_head, *syms_tail, *lazy_head;
static char *env_path, *sys_path;
static unsigned long long gencnt;
static int runtime;
static int ldd_mode;
static int ldso_fail;
static int noload;
static int shutting_down;
static jmp_buf *rtld_fail;
static pthread_rwlock_t lock;
static struct debug debug;
static struct tls_module *tls_tail;
static size_t tls_cnt, tls_offset, tls_align = MIN_TLS_ALIGN;
static size_t static_tls_cnt;
static pthread_mutex_t init_fini_lock;
static pthread_cond_t ctor_cond;
static struct dso *builtin_deps[2];
static struct dso *const no_deps[1];
static struct dso *builtin_ctor_queue[4];
static struct dso **main_ctor_queue;
static struct fdpic_loadmap *app_loadmap;
static struct fdpic_dummy_loadmap app_dummy_loadmap;

struct debug *_dl_debug_addr = &debug;

extern hidden int __malloc_replaced;

hidden void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;

extern hidden void (*const __init_array_end)(void), (*const __fini_array_end)(void);

weak_alias(__init_array_start, __init_array_end);
weak_alias(__fini_array_start, __fini_array_end);

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/* asan path open */
int handle_asan_path_open(int fd, const char *name, ns_t *namespace, char *buf);

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/* add namespace function */
static void *addr2dso(size_t a);
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static void get_sys_path(ns_configor *conf);
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static void dlclose_ns(struct dso *p);
static bool get_app_path(char *path, size_t size)
{
	int l = 0;
	l = readlink("/proc/self/exe", path, size);
	if (l < 0 || l >= size) {
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		LD_LOGE("get_app_path readlink failed!\n");
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		return false;
	}
	path[l] = 0;
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	LD_LOGD("get_app_path path:%s.\n", path);
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	return true;
}

static void init_default_namespace(struct dso *app)
{
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	ns_t *default_ns = get_default_ns();
	memset(default_ns, 0, sizeof *default_ns);
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	ns_set_name(default_ns, NS_DEFAULT_NAME);
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	if (env_path) ns_set_env_paths(default_ns, env_path);
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	ns_set_lib_paths(default_ns, sys_path);
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	ns_set_separated(default_ns, false);
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	app->namespace = default_ns;
	ns_add_dso(default_ns, app);
	LD_LOGD("init_default_namespace default_namespace:"
			"nsname: default ,"
			"lib_paths:%s ,"
			"env_path:%s ,"
			"separated: false.\n",
			sys_path, env_path);
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	return;
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}

static void set_ns_attrs(ns_t *ns, ns_configor *conf)
{
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	if(!ns || !conf) {
		LD_LOGW("set_ns_attrs failed,ns or conf is null!\n");
		return;
	}

	char *lib_paths, *asan_lib_paths, *permitted_paths, *asan_permitted_paths, *allowed_libs;
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	ns_set_separated(ns, conf->get_separated(ns->ns_name));

	lib_paths = conf->get_lib_paths(ns->ns_name);
	if (lib_paths) ns_set_lib_paths(ns, lib_paths);

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	asan_lib_paths = conf->get_asan_lib_paths(ns->ns_name);
	if (asan_lib_paths) ns_set_asan_lib_paths(ns, asan_lib_paths);

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	permitted_paths = conf->get_permitted_paths(ns->ns_name);
	if (permitted_paths) ns_set_permitted_paths(ns, permitted_paths);

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	asan_permitted_paths = conf->get_asan_permitted_paths(ns->ns_name);
	if (asan_permitted_paths) ns_set_asan_permitted_paths(ns, asan_permitted_paths);

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	allowed_libs = conf->get_allowed_libs(ns->ns_name);
	if (allowed_libs) ns_set_allowed_libs(ns, allowed_libs);
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	LD_LOGD("set_ns_attrs :"
			"ns: %p ,"
			"ns_name: %s ,"
			"separated:%d ,"
			"lib_paths:%s ,"
			"asan_lib_paths:%s ,"
			"permitted_paths:%s ,"
			"asan_permitted_paths:%s ,"
			"allowed_libs: %s .\n",
			ns, ns->ns_name, ns->separated, ns->lib_paths, ns->asan_lib_paths, ns->permitted_paths,
			ns->asan_permitted_paths, ns->allowed_libs);
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}

static void set_ns_inherits(ns_t *ns, ns_configor *conf)
{
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	if(!ns || !conf) {
		LD_LOGW("set_ns_inherits failed,ns or conf is null!\n");
		return;
	}

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	strlist *inherits = conf->get_inherits(ns->ns_name);
	if (inherits) {
		for (size_t i=0; i<inherits->num; i++) {
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			ns_t *inherited_ns = find_ns_by_name(inherits->strs[i]);
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			if (inherited_ns) {
				char *shared_libs = conf->get_inherit_shared_libs(ns->ns_name, inherited_ns->ns_name);
				ns_add_inherit(ns, inherited_ns, shared_libs);
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				LD_LOGD("set_ns_inherits :"
						"inherited_ns: %p ,"
						"ns_name: %s ,"
						"separated:%d ,"
						"lib_paths:%s ,"
						"asan_lib_paths:%s ,"
						"permitted_paths:%s ,"
						"asan_permitted_paths:%s ,"
						"allowed_libs: %s .\n",
						inherited_ns, inherited_ns->ns_name, inherited_ns->separated, inherited_ns->lib_paths,
						inherited_ns->asan_lib_paths, inherited_ns->permitted_paths,
						inherited_ns->asan_permitted_paths, inherited_ns->allowed_libs);
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			}
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		}
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		strlist_free(inherits);
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	} else {
		LD_LOGW("set_ns_inherits inherits is NULL!\n");
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	}
}

static void init_namespace(struct dso *app)
{
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	char app_path[PATH_MAX+1];
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	if (!get_app_path(app_path, sizeof app_path)) {
		strcpy(app_path, app->name);
	}
	char *t = strrchr(app_path, '/');
	if (t) {
		*t = 0;
	} else {
		app_path[0] = '.';
		app_path[1] = 0;
	}
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	nslist *nsl = nslist_init();
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	ns_configor *conf = configor_init();
	char file_path[sizeof "/etc/ld-musl-namespace-" + sizeof (LDSO_ARCH) + sizeof ".ini" + 1];
	(void)snprintf(file_path, sizeof file_path, "/etc/ld-musl-namespace-%s.ini", LDSO_ARCH);
	LD_LOGI("init_namespace file_path:%s", file_path);
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	int ret = conf->parse(file_path, app_path);
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	if (ret < 0) {
		LD_LOGE("init_namespace ini file parse failed!\n");
		/* Init_default_namespace is required even if the ini file parsing fails */
		if (!sys_path) get_sys_path(conf);
		init_default_namespace(app);
		configor_free();
		return;
	}

	/* sys_path needs to be parsed through ini file */
	if (!sys_path) get_sys_path(conf);
	init_default_namespace(app);

	/* Init default namespace */
	ns_t *d_ns = get_default_ns();
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	set_ns_attrs(d_ns, conf);
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	/* Init other namespace */
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	if (!nsl) {
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		LD_LOGE("init nslist fail!\n");
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		configor_free();
		return;
	}
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	strlist *s_ns = conf->get_namespaces();
	if (s_ns) {
		for (size_t i=0; i<s_ns->num; i++) {
			ns_t *ns = ns_alloc();
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			ns_set_name(ns, s_ns->strs[i]);
			set_ns_attrs(ns, conf);
			ns_add_dso(ns, app);
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			nslist_add_ns(ns);
		}
		strlist_free(s_ns);
	} 
	/* Set inherited namespace */
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	set_ns_inherits(d_ns, conf);
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	for (size_t i = 0; i < nsl->num; i++) {
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		set_ns_inherits(nsl->nss[i], conf);
	}
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	configor_free();
	return;
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}

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static int dl_strcmp(const char *l, const char *r)
{
	for (; *l==*r && *l; l++, r++);
	return *(unsigned char *)l - *(unsigned char *)r;
}
#define strcmp(l,r) dl_strcmp(l,r)

/* Compute load address for a virtual address in a given dso. */
#if DL_FDPIC
static void *laddr(const struct dso *p, size_t v)
{
	size_t j=0;
	if (!p->loadmap) return p->base + v;
	for (j=0; v-p->loadmap->segs[j].p_vaddr >= p->loadmap->segs[j].p_memsz; j++);
	return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
}
static void *laddr_pg(const struct dso *p, size_t v)
{
	size_t j=0;
	size_t pgsz = PAGE_SIZE;
	if (!p->loadmap) return p->base + v;
	for (j=0; ; j++) {
		size_t a = p->loadmap->segs[j].p_vaddr;
		size_t b = a + p->loadmap->segs[j].p_memsz;
		a &= -pgsz;
		b += pgsz-1;
		b &= -pgsz;
		if (v-a<b-a) break;
	}
	return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
}
static void (*fdbarrier(void *p))()
{
	void (*fd)();
	__asm__("" : "=r"(fd) : "0"(p));
	return fd;
}
#define fpaddr(p, v) fdbarrier((&(struct funcdesc){ \
	laddr(p, v), (p)->got }))
#else
#define laddr(p, v) (void *)((p)->base + (v))
#define laddr_pg(p, v) laddr(p, v)
#define fpaddr(p, v) ((void (*)())laddr(p, v))
#endif

static void decode_vec(size_t *v, size_t *a, size_t cnt)
{
	size_t i;
	for (i=0; i<cnt; i++) a[i] = 0;
	for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
		a[0] |= 1UL<<v[0];
		a[v[0]] = v[1];
	}
}

static int search_vec(size_t *v, size_t *r, size_t key)
{
	for (; v[0]!=key; v+=2)
		if (!v[0]) return 0;
	*r = v[1];
	return 1;
}

static uint32_t sysv_hash(const char *s0)
{
	const unsigned char *s = (void *)s0;
	uint_fast32_t h = 0;
	while (*s) {
		h = 16*h + *s++;
		h ^= h>>24 & 0xf0;
	}
	return h & 0xfffffff;
}

static uint32_t gnu_hash(const char *s0)
{
	const unsigned char *s = (void *)s0;
	uint_fast32_t h = 5381;
	for (; *s; s++)
		h += h*32 + *s;
	return h;
}

static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
{
	size_t i;
	Sym *syms = dso->syms;
	Elf_Symndx *hashtab = dso->hashtab;
	char *strings = dso->strings;
	for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
		if ((!dso->versym || dso->versym[i] >= 0)
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			&& (!strcmp(s, strings+syms[i].st_name)))
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			return syms+i;
	}
	return 0;
}

static Sym *gnu_lookup(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s)
{
	uint32_t nbuckets = hashtab[0];
	uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
	uint32_t i = buckets[h1 % nbuckets];

	if (!i) return 0;

	uint32_t *hashval = buckets + nbuckets + (i - hashtab[1]);

	for (h1 |= 1; ; i++) {
		uint32_t h2 = *hashval++;
		if ((h1 == (h2|1)) && (!dso->versym || dso->versym[i] >= 0)
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			&& !strcmp(s, dso->strings + dso->syms[i].st_name))
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			return dso->syms+i;
		if (h2 & 1) break;
	}

	return 0;
}

static Sym *gnu_lookup_filtered(uint32_t h1, uint32_t *hashtab, struct dso *dso, const char *s, uint32_t fofs, size_t fmask)
{
	const size_t *bloomwords = (const void *)(hashtab+4);
	size_t f = bloomwords[fofs & (hashtab[2]-1)];
	if (!(f & fmask)) return 0;

	f >>= (h1 >> hashtab[3]) % (8 * sizeof f);
	if (!(f & 1)) return 0;

	return gnu_lookup(h1, hashtab, dso, s);
}

#define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON | 1<<STT_TLS)
#define OK_BINDS (1<<STB_GLOBAL | 1<<STB_WEAK | 1<<STB_GNU_UNIQUE)

#ifndef ARCH_SYM_REJECT_UND
#define ARCH_SYM_REJECT_UND(s) 0
#endif

#if defined(__GNUC__)
__attribute__((always_inline))
#endif
static inline struct symdef find_sym2(struct dso *dso, const char *s, int need_def, int use_deps)
{
	uint32_t h = 0, gh = gnu_hash(s), gho = gh / (8*sizeof(size_t)), *ght;
	size_t ghm = 1ul << gh % (8*sizeof(size_t));
	struct symdef def = {0};
	struct dso **deps = use_deps ? dso->deps : 0;
	for (; dso; dso=use_deps ? *deps++ : dso->syms_next) {
		Sym *sym;
		if ((ght = dso->ghashtab)) {
			sym = gnu_lookup_filtered(gh, ght, dso, s, gho, ghm);
		} else {
			if (!h) h = sysv_hash(s);
			sym = sysv_lookup(s, h, dso);
		}
		if (!sym) continue;
		if (!sym->st_shndx)
			if (need_def || (sym->st_info&0xf) == STT_TLS
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				|| ARCH_SYM_REJECT_UND(sym))
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				continue;
		if (!sym->st_value)
			if ((sym->st_info&0xf) != STT_TLS)
				continue;
		if (!(1<<(sym->st_info&0xf) & OK_TYPES)) continue;
		if (!(1<<(sym->st_info>>4) & OK_BINDS)) continue;
		def.sym = sym;
		def.dso = dso;
		break;
	}
	return def;
}

static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
{
	return find_sym2(dso, s, need_def, 0);
}

static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
{
	unsigned char *base = dso->base;
	Sym *syms = dso->syms;
	char *strings = dso->strings;
	Sym *sym;
	const char *name;
	void *ctx;
	int type;
	int sym_index;
	struct symdef def;
	size_t *reloc_addr;
	size_t sym_val;
	size_t tls_val;
	size_t addend;
	int skip_relative = 0, reuse_addends = 0, save_slot = 0;

	if (dso == &ldso) {
		/* Only ldso's REL table needs addend saving/reuse. */
		if (rel == apply_addends_to)
			reuse_addends = 1;
		skip_relative = 1;
	}

	for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
		if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue;
		type = R_TYPE(rel[1]);
		if (type == REL_NONE) continue;
		reloc_addr = laddr(dso, rel[0]);

		if (stride > 2) {
			addend = rel[2];
		} else if (type==REL_GOT || type==REL_PLT|| type==REL_COPY) {
			addend = 0;
		} else if (reuse_addends) {
			/* Save original addend in stage 2 where the dso
			 * chain consists of just ldso; otherwise read back
			 * saved addend since the inline one was clobbered. */
			if (head==&ldso)
				saved_addends[save_slot] = *reloc_addr;
			addend = saved_addends[save_slot++];
		} else {
			addend = *reloc_addr;
		}

		sym_index = R_SYM(rel[1]);
		if (sym_index) {
			sym = syms + sym_index;
			name = strings + sym->st_name;
			ctx = type==REL_COPY ? head->syms_next : head;
			def = (sym->st_info>>4) == STB_LOCAL
				? (struct symdef){ .dso = dso, .sym = sym }
				: find_sym(ctx, name, type==REL_PLT);
			if (!def.sym && (sym->st_shndx != SHN_UNDEF
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				|| sym->st_info>>4 != STB_WEAK)) {
576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597
				if (dso->lazy && (type==REL_PLT || type==REL_GOT)) {
					dso->lazy[3*dso->lazy_cnt+0] = rel[0];
					dso->lazy[3*dso->lazy_cnt+1] = rel[1];
					dso->lazy[3*dso->lazy_cnt+2] = addend;
					dso->lazy_cnt++;
					continue;
				}
				error("Error relocating %s: %s: symbol not found",
					dso->name, name);
				if (runtime) longjmp(*rtld_fail, 1);
				continue;
			}
		} else {
			sym = 0;
			def.sym = 0;
			def.dso = dso;
		}

		sym_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
		tls_val = def.sym ? def.sym->st_value : 0;

		if ((type == REL_TPOFF || type == REL_TPOFF_NEG)
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			&& def.dso->tls_id > static_tls_cnt) {
599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 894 895 896 897 898 899 900 901 902 903 904 905 906 907 908 909 910 911 912 913 914 915 916 917 918 919 920 921 922 923 924 925 926 927 928 929 930 931 932 933 934
			error("Error relocating %s: %s: initial-exec TLS "
				"resolves to dynamic definition in %s",
				dso->name, name, def.dso->name);
			longjmp(*rtld_fail, 1);
		}

		switch(type) {
		case REL_NONE:
			break;
		case REL_OFFSET:
			addend -= (size_t)reloc_addr;
		case REL_SYMBOLIC:
		case REL_GOT:
		case REL_PLT:
			*reloc_addr = sym_val + addend;
			break;
		case REL_USYMBOLIC:
			memcpy(reloc_addr, &(size_t){sym_val + addend}, sizeof(size_t));
			break;
		case REL_RELATIVE:
			*reloc_addr = (size_t)base + addend;
			break;
		case REL_SYM_OR_REL:
			if (sym) *reloc_addr = sym_val + addend;
			else *reloc_addr = (size_t)base + addend;
			break;
		case REL_COPY:
			memcpy(reloc_addr, (void *)sym_val, sym->st_size);
			break;
		case REL_OFFSET32:
			*(uint32_t *)reloc_addr = sym_val + addend
				- (size_t)reloc_addr;
			break;
		case REL_FUNCDESC:
			*reloc_addr = def.sym ? (size_t)(def.dso->funcdescs
				+ (def.sym - def.dso->syms)) : 0;
			break;
		case REL_FUNCDESC_VAL:
			if ((sym->st_info&0xf) == STT_SECTION) *reloc_addr += sym_val;
			else *reloc_addr = sym_val;
			reloc_addr[1] = def.sym ? (size_t)def.dso->got : 0;
			break;
		case REL_DTPMOD:
			*reloc_addr = def.dso->tls_id;
			break;
		case REL_DTPOFF:
			*reloc_addr = tls_val + addend - DTP_OFFSET;
			break;
#ifdef TLS_ABOVE_TP
		case REL_TPOFF:
			*reloc_addr = tls_val + def.dso->tls.offset + TPOFF_K + addend;
			break;
#else
		case REL_TPOFF:
			*reloc_addr = tls_val - def.dso->tls.offset + addend;
			break;
		case REL_TPOFF_NEG:
			*reloc_addr = def.dso->tls.offset - tls_val + addend;
			break;
#endif
		case REL_TLSDESC:
			if (stride<3) addend = reloc_addr[1];
			if (def.dso->tls_id > static_tls_cnt) {
				struct td_index *new = malloc(sizeof *new);
				if (!new) {
					error(
					"Error relocating %s: cannot allocate TLSDESC for %s",
					dso->name, sym ? name : "(local)" );
					longjmp(*rtld_fail, 1);
				}
				new->next = dso->td_index;
				dso->td_index = new;
				new->args[0] = def.dso->tls_id;
				new->args[1] = tls_val + addend - DTP_OFFSET;
				reloc_addr[0] = (size_t)__tlsdesc_dynamic;
				reloc_addr[1] = (size_t)new;
			} else {
				reloc_addr[0] = (size_t)__tlsdesc_static;
#ifdef TLS_ABOVE_TP
				reloc_addr[1] = tls_val + def.dso->tls.offset
					+ TPOFF_K + addend;
#else
				reloc_addr[1] = tls_val - def.dso->tls.offset
					+ addend;
#endif
			}
#ifdef TLSDESC_BACKWARDS
			/* Some archs (32-bit ARM at least) invert the order of
			 * the descriptor members. Fix them up here. */
			size_t tmp = reloc_addr[0];
			reloc_addr[0] = reloc_addr[1];
			reloc_addr[1] = tmp;
#endif
			break;
		default:
			error("Error relocating %s: unsupported relocation type %d",
				dso->name, type);
			if (runtime) longjmp(*rtld_fail, 1);
			continue;
		}
	}
}

static void redo_lazy_relocs()
{
	struct dso *p = lazy_head, *next;
	lazy_head = 0;
	for (; p; p=next) {
		next = p->lazy_next;
		size_t size = p->lazy_cnt*3*sizeof(size_t);
		p->lazy_cnt = 0;
		do_relocs(p, p->lazy, size, 3);
		if (p->lazy_cnt) {
			p->lazy_next = lazy_head;
			lazy_head = p;
		} else {
			free(p->lazy);
			p->lazy = 0;
			p->lazy_next = 0;
		}
	}
}

/* A huge hack: to make up for the wastefulness of shared libraries
 * needing at least a page of dirty memory even if they have no global
 * data, we reclaim the gaps at the beginning and end of writable maps
 * and "donate" them to the heap. */

static void reclaim(struct dso *dso, size_t start, size_t end)
{
	if (start >= dso->relro_start && start < dso->relro_end) start = dso->relro_end;
	if (end   >= dso->relro_start && end   < dso->relro_end) end = dso->relro_start;
	if (start >= end) return;
	char *base = laddr_pg(dso, start);
	__malloc_donate(base, base+(end-start));
}

static void reclaim_gaps(struct dso *dso)
{
	Phdr *ph = dso->phdr;
	size_t phcnt = dso->phnum;

	for (; phcnt--; ph=(void *)((char *)ph+dso->phentsize)) {
		if (ph->p_type!=PT_LOAD) continue;
		if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
		reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
		reclaim(dso, ph->p_vaddr+ph->p_memsz,
			ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
	}
}

static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t off)
{
	static int no_map_fixed;
	char *q;
	if (!no_map_fixed) {
		q = mmap(p, n, prot, flags|MAP_FIXED, fd, off);
		if (!DL_NOMMU_SUPPORT || q != MAP_FAILED || errno != EINVAL)
			return q;
		no_map_fixed = 1;
	}
	/* Fallbacks for MAP_FIXED failure on NOMMU kernels. */
	if (flags & MAP_ANONYMOUS) {
		memset(p, 0, n);
		return p;
	}
	ssize_t r;
	if (lseek(fd, off, SEEK_SET) < 0) return MAP_FAILED;
	for (q=p; n; q+=r, off+=r, n-=r) {
		r = read(fd, q, n);
		if (r < 0 && errno != EINTR) return MAP_FAILED;
		if (!r) {
			memset(q, 0, n);
			break;
		}
	}
	return p;
}

static void unmap_library(struct dso *dso)
{
	if (dso->loadmap) {
		size_t i;
		for (i=0; i<dso->loadmap->nsegs; i++) {
			if (!dso->loadmap->segs[i].p_memsz)
				continue;
			munmap((void *)dso->loadmap->segs[i].addr,
				dso->loadmap->segs[i].p_memsz);
		}
		free(dso->loadmap);
	} else if (dso->map && dso->map_len) {
		munmap(dso->map, dso->map_len);
	}
}

static void *map_library(int fd, struct dso *dso)
{
	Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
	void *allocated_buf=0;
	size_t phsize;
	size_t addr_min=SIZE_MAX, addr_max=0, map_len;
	size_t this_min, this_max;
	size_t nsegs = 0;
	off_t off_start;
	Ehdr *eh;
	Phdr *ph, *ph0;
	unsigned prot;
	unsigned char *map=MAP_FAILED, *base;
	size_t dyn=0;
	size_t tls_image=0;
	size_t i;

	ssize_t l = read(fd, buf, sizeof buf);
	eh = buf;
	if (l<0) return 0;
	if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
		goto noexec;
	phsize = eh->e_phentsize * eh->e_phnum;
	if (phsize > sizeof buf - sizeof *eh) {
		allocated_buf = malloc(phsize);
		if (!allocated_buf) return 0;
		l = pread(fd, allocated_buf, phsize, eh->e_phoff);
		if (l < 0) goto error;
		if (l != phsize) goto noexec;
		ph = ph0 = allocated_buf;
	} else if (eh->e_phoff + phsize > l) {
		l = pread(fd, buf+1, phsize, eh->e_phoff);
		if (l < 0) goto error;
		if (l != phsize) goto noexec;
		ph = ph0 = (void *)(buf + 1);
	} else {
		ph = ph0 = (void *)((char *)buf + eh->e_phoff);
	}
	for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
		if (ph->p_type == PT_DYNAMIC) {
			dyn = ph->p_vaddr;
		} else if (ph->p_type == PT_TLS) {
			tls_image = ph->p_vaddr;
			dso->tls.align = ph->p_align;
			dso->tls.len = ph->p_filesz;
			dso->tls.size = ph->p_memsz;
		} else if (ph->p_type == PT_GNU_RELRO) {
			dso->relro_start = ph->p_vaddr & -PAGE_SIZE;
			dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
		} else if (ph->p_type == PT_GNU_STACK) {
			if (!runtime && ph->p_memsz > __default_stacksize) {
				__default_stacksize =
					ph->p_memsz < DEFAULT_STACK_MAX ?
					ph->p_memsz : DEFAULT_STACK_MAX;
			}
		}
		if (ph->p_type != PT_LOAD) continue;
		nsegs++;
		if (ph->p_vaddr < addr_min) {
			addr_min = ph->p_vaddr;
			off_start = ph->p_offset;
			prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
				((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
				((ph->p_flags&PF_X) ? PROT_EXEC : 0));
		}
		if (ph->p_vaddr+ph->p_memsz > addr_max) {
			addr_max = ph->p_vaddr+ph->p_memsz;
		}
	}
	if (!dyn) goto noexec;
	if (DL_FDPIC && !(eh->e_flags & FDPIC_CONSTDISP_FLAG)) {
		dso->loadmap = calloc(1, sizeof *dso->loadmap
			+ nsegs * sizeof *dso->loadmap->segs);
		if (!dso->loadmap) goto error;
		dso->loadmap->nsegs = nsegs;
		for (ph=ph0, i=0; i<nsegs; ph=(void *)((char *)ph+eh->e_phentsize)) {
			if (ph->p_type != PT_LOAD) continue;
			prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
				((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
				((ph->p_flags&PF_X) ? PROT_EXEC : 0));
			map = mmap(0, ph->p_memsz + (ph->p_vaddr & PAGE_SIZE-1),
				prot, MAP_PRIVATE,
				fd, ph->p_offset & -PAGE_SIZE);
			if (map == MAP_FAILED) {
				unmap_library(dso);
				goto error;
			}
			dso->loadmap->segs[i].addr = (size_t)map +
				(ph->p_vaddr & PAGE_SIZE-1);
			dso->loadmap->segs[i].p_vaddr = ph->p_vaddr;
			dso->loadmap->segs[i].p_memsz = ph->p_memsz;
			i++;
			if (prot & PROT_WRITE) {
				size_t brk = (ph->p_vaddr & PAGE_SIZE-1)
					+ ph->p_filesz;
				size_t pgbrk = brk + PAGE_SIZE-1 & -PAGE_SIZE;
				size_t pgend = brk + ph->p_memsz - ph->p_filesz
					+ PAGE_SIZE-1 & -PAGE_SIZE;
				if (pgend > pgbrk && mmap_fixed(map+pgbrk,
					pgend-pgbrk, prot,
					MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS,
					-1, off_start) == MAP_FAILED)
					goto error;
				memset(map + brk, 0, pgbrk-brk);
			}
		}
		map = (void *)dso->loadmap->segs[0].addr;
		map_len = 0;
		goto done_mapping;
	}
	addr_max += PAGE_SIZE-1;
	addr_max &= -PAGE_SIZE;
	addr_min &= -PAGE_SIZE;
	off_start &= -PAGE_SIZE;
	map_len = addr_max - addr_min + off_start;
	/* The first time, we map too much, possibly even more than
	 * the length of the file. This is okay because we will not
	 * use the invalid part; we just need to reserve the right
	 * amount of virtual address space to map over later. */
	map = DL_NOMMU_SUPPORT
		? mmap((void *)addr_min, map_len, PROT_READ|PROT_WRITE|PROT_EXEC,
			MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
		: mmap((void *)addr_min, map_len, prot,
			MAP_PRIVATE, fd, off_start);
	if (map==MAP_FAILED) goto error;
	dso->map = map;
	dso->map_len = map_len;
	/* If the loaded file is not relocatable and the requested address is
	 * not available, then the load operation must fail. */
	if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
		errno = EBUSY;
		goto error;
	}
	base = map - addr_min;
	dso->phdr = 0;
	dso->phnum = 0;
	for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
		if (ph->p_type != PT_LOAD) continue;
		/* Check if the programs headers are in this load segment, and
		 * if so, record the address for use by dl_iterate_phdr. */
		if (!dso->phdr && eh->e_phoff >= ph->p_offset
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			&& eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961
			dso->phdr = (void *)(base + ph->p_vaddr
				+ (eh->e_phoff-ph->p_offset));
			dso->phnum = eh->e_phnum;
			dso->phentsize = eh->e_phentsize;
		}
		this_min = ph->p_vaddr & -PAGE_SIZE;
		this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
		off_start = ph->p_offset & -PAGE_SIZE;
		prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
			((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
			((ph->p_flags&PF_X) ? PROT_EXEC : 0));
		/* Reuse the existing mapping for the lowest-address LOAD */
		if ((ph->p_vaddr & -PAGE_SIZE) != addr_min || DL_NOMMU_SUPPORT)
			if (mmap_fixed(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
				goto error;
		if (ph->p_memsz > ph->p_filesz && (ph->p_flags&PF_W)) {
			size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
			size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
			memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
			if (pgbrk-(size_t)base < this_max && mmap_fixed((void *)pgbrk, (size_t)base+this_max-pgbrk, prot, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) == MAP_FAILED)
				goto error;
		}
	}
	for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
		if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
			if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC)
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				&& errno != ENOSYS)
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				goto error;
			break;
		}
done_mapping:
	dso->base = base;
	dso->dynv = laddr(dso, dyn);
	if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);
	free(allocated_buf);
	return map;
noexec:
	errno = ENOEXEC;
error:
	if (map!=MAP_FAILED) unmap_library(dso);
	free(allocated_buf);
	return 0;
}

static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
{
	size_t l;
	int fd;
	for (;;) {
		s += strspn(s, ":\n");
		l = strcspn(s, ":\n");
		if (l-1 >= INT_MAX) return -1;
		if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_size) {
			if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
			switch (errno) {
			case ENOENT:
			case ENOTDIR:
			case EACCES:
			case ENAMETOOLONG:
				break;
			default:
				/* Any negative value but -1 will inhibit
				 * futher path search. */
				return -2;
			}
		}
		s += l;
	}
}

static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
{
	size_t n, l;
	const char *s, *t, *origin;
	char *d;
	if (p->rpath || !p->rpath_orig) return 0;
	if (!strchr(p->rpath_orig, '$')) {
		p->rpath = p->rpath_orig;
		return 0;
	}
	n = 0;
	s = p->rpath_orig;
	while ((t=strchr(s, '$'))) {
		if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))
			return 0;
		s = t+1;
		n++;
	}
	if (n > SSIZE_MAX/PATH_MAX) return 0;

	if (p->kernel_mapped) {
		/* $ORIGIN searches cannot be performed for the main program
		 * when it is suid/sgid/AT_SECURE. This is because the
		 * pathname is under the control of the caller of execve.
		 * For libraries, however, $ORIGIN can be processed safely
		 * since the library's pathname came from a trusted source
		 * (either system paths or a call to dlopen). */
		if (libc.secure)
			return 0;
		l = readlink("/proc/self/exe", buf, buf_size);
		if (l == -1) switch (errno) {
		case ENOENT:
		case ENOTDIR:
		case EACCES:
			break;
		default:
			return -1;
		}
		if (l >= buf_size)
			return 0;
		buf[l] = 0;
		origin = buf;
	} else {
		origin = p->name;
	}
	t = strrchr(origin, '/');
	if (t) {
		l = t-origin;
	} else {
		/* Normally p->name will always be an absolute or relative
		 * pathname containing at least one '/' character, but in the
		 * case where ldso was invoked as a command to execute a
		 * program in the working directory, app.name may not. Fix. */
		origin = ".";
		l = 1;
	}
	/* Disallow non-absolute origins for suid/sgid/AT_SECURE. */
	if (libc.secure && *origin != '/')
		return 0;
	p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
	if (!p->rpath) return -1;

	d = p->rpath;
	s = p->rpath_orig;
	while ((t=strchr(s, '$'))) {
		memcpy(d, s, t-s);
		d += t-s;
		memcpy(d, origin, l);
		d += l;
		/* It was determined previously that the '$' is followed
		 * either by "ORIGIN" or "{ORIGIN}". */
		s = t + 7 + 2*(t[1]=='{');
	}
	strcpy(d, s);
	return 0;
}

static void decode_dyn(struct dso *p)
{
	size_t dyn[DYN_CNT];
	decode_vec(p->dynv, dyn, DYN_CNT);
	p->syms = laddr(p, dyn[DT_SYMTAB]);
	p->strings = laddr(p, dyn[DT_STRTAB]);
	if (dyn[0]&(1<<DT_HASH))
		p->hashtab = laddr(p, dyn[DT_HASH]);
	if (dyn[0]&(1<<DT_RPATH))
		p->rpath_orig = p->strings + dyn[DT_RPATH];
	if (dyn[0]&(1<<DT_RUNPATH))
		p->rpath_orig = p->strings + dyn[DT_RUNPATH];
	if (dyn[0]&(1<<DT_PLTGOT))
		p->got = laddr(p, dyn[DT_PLTGOT]);
	if (search_vec(p->dynv, dyn, DT_GNU_HASH))
		p->ghashtab = laddr(p, *dyn);
	if (search_vec(p->dynv, dyn, DT_VERSYM))
		p->versym = laddr(p, *dyn);
}

static size_t count_syms(struct dso *p)
{
	if (p->hashtab) return p->hashtab[1];

	size_t nsym, i;
	uint32_t *buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
	uint32_t *hashval;
	for (i = nsym = 0; i < p->ghashtab[0]; i++) {
		if (buckets[i] > nsym)
			nsym = buckets[i];
	}
	if (nsym) {
		hashval = buckets + p->ghashtab[0] + (nsym - p->ghashtab[1]);
		do nsym++;
		while (!(*hashval++ & 1));
	}
	return nsym;
}

static void *dl_mmap(size_t n)
{
	void *p;
	int prot = PROT_READ|PROT_WRITE, flags = MAP_ANONYMOUS|MAP_PRIVATE;
#ifdef SYS_mmap2
	p = (void *)__syscall(SYS_mmap2, 0, n, prot, flags, -1, 0);
#else
	p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0);
#endif
	return (unsigned long)p > -4096UL ? 0 : p;
}

static void makefuncdescs(struct dso *p)
{
	static int self_done;
	size_t nsym = count_syms(p);
	size_t i, size = nsym * sizeof(*p->funcdescs);

	if (!self_done) {
		p->funcdescs = dl_mmap(size);
		self_done = 1;
	} else {
		p->funcdescs = malloc(size);
	}
	if (!p->funcdescs) {
		if (!runtime) a_crash();
		error("Error allocating function descriptors for %s", p->name);
		longjmp(*rtld_fail, 1);
	}
	for (i=0; i<nsym; i++) {
		if ((p->syms[i].st_info&0xf)==STT_FUNC && p->syms[i].st_shndx) {
			p->funcdescs[i].addr = laddr(p, p->syms[i].st_value);
			p->funcdescs[i].got = p->got;
		} else {
			p->funcdescs[i].addr = 0;
			p->funcdescs[i].got = 0;
		}
	}
}

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static void get_sys_path(ns_configor *conf)
{ 
	LD_LOGD("get_sys_path g_is_asan:%d\n", g_is_asan);
	/* Use ini file's system paths when Asan is not enabled */
	if (!g_is_asan) {
		sys_path = conf->get_sys_paths();
	} else {
		/* Use ini file's asan system paths when the Asan is enabled
		 * Merge two strings when both sys_paths and asan_sys_paths are valid */
		sys_path = conf->get_asan_sys_paths();
		char *sys_path_default = conf->get_sys_paths();
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		if (!sys_path) {
			sys_path = sys_path_default;
		} else if (sys_path_default) {
			size_t newlen = strlen(sys_path) + strlen(sys_path_default) + 2;
			char *new_syspath = malloc(newlen);
			memset(new_syspath, 0, newlen);
			strcpy(new_syspath, sys_path);
			strcat(new_syspath, ":");
			strcat(new_syspath, sys_path_default);
			sys_path = new_syspath;
		}
	}
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	if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib:/lib64";
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	LD_LOGD("get_sys_path sys_path:%s\n", sys_path);
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}

static struct dso *search_dso_by_name(const char *name, const ns_t *ns) {
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	LD_LOGD("search_dso_by_name name:%s, ns:%p\n", name, ns);
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	for (size_t i = 0; i < ns->ns_dsos->num; i++){
		struct dso *p = ns->ns_dsos->dsos[i];
		if (p->shortname && !strcmp(p->shortname, name)) {
			return p;
		}
	}
	return NULL;
}

static struct dso *search_dso_by_fstat(const struct stat *st, const ns_t *ns) {
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	LD_LOGD("search_dso_by_fstat st->st_dev:%lu, st->st_ino:%lu, ns:%p\n", st->st_dev, st->st_ino, ns);
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	for (size_t i = 0; i < ns->ns_dsos->num; i++){
		struct dso *p = ns->ns_dsos->dsos[i];
		if (p->dev == st->st_dev && p->ino == st->st_ino) {
			return p;
		}
	}
	return NULL;
}
/* Find loaded so by name */
static struct dso *find_library_by_name(const char *name, const ns_t *ns, bool check_inherited)
{	
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	LD_LOGD("find_library_by_name name:%s, ns:%p, check_inherited:%d\n", name, ns, check_inherited);
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	struct dso *p = search_dso_by_name(name, ns);
	if (p) return p;
	if (check_inherited && ns->ns_inherits) {
		for (size_t i = 0; i < ns->ns_inherits->num; i++){
			ns_inherit * inherit = ns->ns_inherits->inherits[i];
			p = search_dso_by_name(name, inherit->inherited_ns);
			if (p && is_sharable(inherit, name)) return p;
		}
	}
	return NULL;
}
/* Find loaded so by file stat */
static struct dso *find_library_by_fstat(const struct stat *st, const ns_t *ns, bool check_inherited) {
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	LD_LOGD("find_library_by_fstat st->st_dev:%lu, st->st_ino:%lu, ns:%p, check_inherited:%d\n", st->st_dev, st->st_ino, ns, check_inherited);
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	struct dso *p = search_dso_by_fstat(st, ns);
	if (p) return p;
	if (check_inherited && ns->ns_inherits) {
		for (size_t i = 0; i < ns->ns_inherits->num; i++){
			ns_inherit *inherit = ns->ns_inherits->inherits[i];
			p = search_dso_by_fstat(st, inherit->inherited_ns);
			if (p && is_sharable(inherit, p->shortname)) return p;
		}
	}
	return NULL;
}
/* add namespace function */
struct dso *load_library(const char *name, struct dso *needed_by, ns_t *namespace, bool check_inherited)
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{
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	char buf[PATH_MAX+1];
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	const char *pathname;
	unsigned char *map;
	struct dso *p, temp_dso = {0};
	int fd;
	struct stat st;
	size_t alloc_size;
	int n_th = 0;
	int is_self = 0;

	if (!*name) {
		errno = EINVAL;
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		LD_LOGW("load_library name is null!\n");
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		return 0;
	}

	/* Catch and block attempts to reload the implementation itself */
	if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
		static const char reserved[] =
			"c.pthread.rt.m.dl.util.xnet.";
		const char *rp, *next;
		for (rp=reserved; *rp; rp=next) {
			next = strchr(rp, '.') + 1;
			if (strncmp(name+3, rp, next-rp) == 0)
				break;
		}
		if (*rp) {
			if (ldd_mode) {
				/* Track which names have been resolved
				 * and only report each one once. */
				static unsigned reported;
				unsigned mask = 1U<<(rp-reserved);
				if (!(reported & mask)) {
					reported |= mask;
					dprintf(1, "\t%s => %s (%p)\n",
						name, ldso.name,
						ldso.base);
				}
			}
			is_self = 1;
		}
	}
	if (!strcmp(name, ldso.name)) is_self = 1;
	if (is_self) {
		if (!ldso.prev) {
			tail->next = &ldso;
			ldso.prev = tail;
			tail = &ldso;
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			ldso.namespace = namespace;
			ns_add_dso(namespace, &ldso);
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		}
		/* increase libc dlopen refcnt */
		a_inc(&ldso.nr_dlopen);
		return &ldso;
	}
	if (strchr(name, '/')) {
		pathname = name;
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		if (!is_accessible(namespace, pathname, g_is_asan, check_inherited)) {
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			fd = -1;
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			LD_LOGD("load_library is_accessible return false,fd = -1!\n");
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		} else {
			fd = open(name, O_RDONLY|O_CLOEXEC);
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			LD_LOGD("load_library is_accessible return true, open file fd:%d .\n", fd);
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		}
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	} else {
		/* Search for the name to see if it's already loaded */
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		/* Search in namespace */
		p = find_library_by_name(name, namespace, check_inherited);
		if (p) {
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			LD_LOGD("load_library find_library_by_name found p, return it!\n");
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			/* increase dlopen refcnt */
			a_inc(&p->nr_dlopen);
			return p;
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		}
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		if (strlen(name) > NAME_MAX) {
			LD_LOGW("load_library name exceeding the maximum length, return 0!\n");
			return 0;
		}
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		fd = -1;
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		if (namespace->env_paths) fd = path_open(name, namespace->env_paths, buf, sizeof buf);
		for (p = needed_by; fd == -1 && p; p = p->needed_by) {
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			if (fixup_rpath(p, buf, sizeof buf) < 0) {
				LD_LOGD("load_library Inhibit further search,fd = -2.\n");
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				fd = -2; /* Inhibit further search. */
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			}
			if (p->rpath) {
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				fd = path_open(name, p->rpath, buf, sizeof buf);
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				LD_LOGD("load_library  p->rpath path_open fd:%d.\n", fd);
			}

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		}
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		if (g_is_asan) {
			fd = handle_asan_path_open(fd, name, namespace, buf);
			LD_LOGD("load_library handle_asan_path_open fd:%d.\n", fd);
		} else {
			if (fd == -1 && namespace->lib_paths) {
				fd = path_open(name, namespace->lib_paths, buf, sizeof buf);
				LD_LOGD("load_library no asan lib_paths path_open fd:%d.\n", fd);
			}
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		}
		pathname = buf;
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		LD_LOGD("load_library lib_paths pathname:%s.\n", pathname);
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	}
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	if (fd < 0) {
		if (!check_inherited || !namespace->ns_inherits) return 0;
		/* Load lib in inherited namespace. Do not check inherited again.*/
		for (size_t i = 0; i < namespace->ns_inherits->num; i++) {
			ns_inherit *inherit = namespace->ns_inherits->inherits[i];
			if (strchr(name, '/')==0 && !is_sharable(inherit, name)) continue;
			p = load_library(name, needed_by, inherit->inherited_ns, false);
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			if (p) {
				LD_LOGD("load_library search in inherited, found p ,inherited_ns name:%s\n",
						inherit->inherited_ns->ns_name);
				return p;
			}
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		}
		return 0;
	}
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	if (fstat(fd, &st) < 0) {
		close(fd);
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		LD_LOGD("load_library fstat < 0,return 0!\n");
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		return 0;
	}
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	/* Search in namespace */
	p = find_library_by_fstat(&st, namespace, check_inherited);
	if (p) {
		/* If this library was previously loaded with a
		* pathname but a search found the same inode,
		* setup its shortname so it can be found by name. */
		if (!p->shortname && pathname != name)
			p->shortname = strrchr(p->name, '/')+1;
		close(fd);
		/* increase dlopen refcnt */
		a_inc(&p->nr_dlopen);
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		LD_LOGD("load_library find_library_by_fstat, found p and return it!\n");
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		return p;
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	}
	map = noload ? 0 : map_library(fd, &temp_dso);
	close(fd);
	if (!map) return 0;

	/* Avoid the danger of getting two versions of libc mapped into the
	 * same process when an absolute pathname was used. The symbols
	 * checked are chosen to catch both musl and glibc, and to avoid
	 * false positives from interposition-hack libraries. */
	decode_dyn(&temp_dso);
	if (find_sym(&temp_dso, "__libc_start_main", 1).sym &&
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		find_sym(&temp_dso, "stdin", 1).sym) {
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		unmap_library(&temp_dso);
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		return load_library("libc.so", needed_by, namespace, true);
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	}
	/* Past this point, if we haven't reached runtime yet, ldso has
	 * committed either to use the mapped library or to abort execution.
	 * Unmapping is not possible, so we can safely reclaim gaps. */
	if (!runtime) reclaim_gaps(&temp_dso);

	/* Allocate storage for the new DSO. When there is TLS, this
	 * storage must include a reservation for all pre-existing
	 * threads to obtain copies of both the new TLS, and an
	 * extended DTV capable of storing an additional slot for
	 * the newly-loaded DSO. */
	alloc_size = sizeof *p + strlen(pathname) + 1;
	if (runtime && temp_dso.tls.image) {
		size_t per_th = temp_dso.tls.size + temp_dso.tls.align
			+ sizeof(void *) * (tls_cnt+3);
		n_th = libc.threads_minus_1 + 1;
		if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
		else alloc_size += n_th * per_th;
	}
	p = calloc(1, alloc_size);
	if (!p) {
		unmap_library(&temp_dso);
		return 0;
	}
	memcpy(p, &temp_dso, sizeof temp_dso);
	p->dev = st.st_dev;
	p->ino = st.st_ino;
	p->needed_by = needed_by;
	p->name = p->buf;
	p->nr_dlopen = 1;
	p->runtime_loaded = runtime;
	strcpy(p->name, pathname);
	/* Add a shortname only if name arg was not an explicit pathname. */
	if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
	if (p->tls.image) {
		p->tls_id = ++tls_cnt;
		tls_align = MAXP2(tls_align, p->tls.align);
#ifdef TLS_ABOVE_TP
		p->tls.offset = tls_offset + ( (p->tls.align-1) &
			(-tls_offset + (uintptr_t)p->tls.image) );
		tls_offset = p->tls.offset + p->tls.size;
#else
		tls_offset += p->tls.size + p->tls.align - 1;
		tls_offset -= (tls_offset + (uintptr_t)p->tls.image)
			& (p->tls.align-1);
		p->tls.offset = tls_offset;
#endif
		p->new_dtv = (void *)(-sizeof(size_t) &
			(uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
		p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
		if (tls_tail) tls_tail->next = &p->tls;
		else libc.tls_head = &p->tls;
		tls_tail = &p->tls;
	}

	tail->next = p;
	p->prev = tail;
	tail = p;

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	/* Add dso to namespace */
	p->namespace = namespace;
	ns_add_dso(namespace, p);
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	if (runtime)
		p->by_dlopen = 1;

	if (DL_FDPIC) makefuncdescs(p);

	if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);

	return p;
}

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static void load_direct_deps(struct dso *p, ns_t *namespace)
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{
	size_t i, cnt=0;

	if (p->deps) return;
	/* For head, all preloads are direct pseudo-dependencies.
	 * Count and include them now to avoid realloc later. */
	if (p==head) for (struct dso *q=p->next; q; q=q->next)
		cnt++;
	for (i=0; p->dynv[i]; i+=2)
		if (p->dynv[i] == DT_NEEDED) cnt++;
	/* Use builtin buffer for apps with no external deps, to
	 * preserve property of no runtime failure paths. */
	p->deps = (p==head && cnt<2) ? builtin_deps :
		calloc(cnt+1, sizeof *p->deps);
	if (!p->deps) {
		error("Error loading dependencies for %s", p->name);
		if (runtime) longjmp(*rtld_fail, 1);
	}
	cnt=0;
	if (p==head) for (struct dso *q=p->next; q; q=q->next)
		p->deps[cnt++] = q;
	for (i=0; p->dynv[i]; i+=2) {
		if (p->dynv[i] != DT_NEEDED) continue;
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		struct dso *dep = load_library(p->strings + p->dynv[i+1], p, namespace, true);
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		if (!dep) {
			error("Error loading shared library %s: %m (needed by %s)",
				p->strings + p->dynv[i+1], p->name);
			if (runtime) longjmp(*rtld_fail, 1);
			continue;
		}
		p->deps[cnt++] = dep;
	}
	p->deps[cnt] = 0;
	p->ndeps_direct = cnt;
}

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static void load_deps(struct dso *p, ns_t *ns)
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{
	if (p->deps) return;
	for (; p; p=p->next)
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		load_direct_deps(p, ns);
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}

static void extend_bfs_deps(struct dso *p)
{
	size_t i, j, cnt, ndeps_all;
	struct dso **tmp;

	/* Can't use realloc if the original p->deps was allocated at
	 * program entry and malloc has been replaced, or if it's
	 * the builtin non-allocated trivial main program deps array. */
	int no_realloc = (__malloc_replaced && !p->runtime_loaded)
		|| p->deps == builtin_deps;

	if (p->bfs_built) return;
	ndeps_all = p->ndeps_direct;

	/* Mark existing (direct) deps so they won't be duplicated. */
	for (i=0; p->deps[i]; i++)
		p->deps[i]->mark = 1;

	/* For each dependency already in the list, copy its list of direct
	 * dependencies to the list, excluding any items already in the
	 * list. Note that the list this loop iterates over will grow during
	 * the loop, but since duplicates are excluded, growth is bounded. */
	for (i=0; p->deps[i]; i++) {
		struct dso *dep = p->deps[i];
		for (j=cnt=0; j<dep->ndeps_direct; j++)
			if (!dep->deps[j]->mark) cnt++;
		tmp = no_realloc ? 
			malloc(sizeof(*tmp) * (ndeps_all+cnt+1)) :
			realloc(p->deps, sizeof(*tmp) * (ndeps_all+cnt+1));
		if (!tmp) {
			error("Error recording dependencies for %s", p->name);
			if (runtime) longjmp(*rtld_fail, 1);
			continue;
		}
		if (no_realloc) {
			memcpy(tmp, p->deps, sizeof(*tmp) * (ndeps_all+1));
			no_realloc = 0;
		}
		p->deps = tmp;
		for (j=0; j<dep->ndeps_direct; j++) {
			if (dep->deps[j]->mark) continue;
			dep->deps[j]->mark = 1;
			p->deps[ndeps_all++] = dep->deps[j];
		}
		p->deps[ndeps_all] = 0;
	}
	p->bfs_built = 1;
	for (p=head; p; p=p->next)
		p->mark = 0;
}

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static void load_preload(char *s, ns_t *ns)
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{
	int tmp;
	char *z;
	for (z=s; *z; s=z) {
		for (   ; *s && (isspace(*s) || *s==':'); s++);
		for (z=s; *z && !isspace(*z) && *z!=':'; z++);
		tmp = *z;
		*z = 0;
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		load_library(s, 0, ns, true);
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		*z = tmp;
	}
}

static void add_syms(struct dso *p)
{
	if (!p->syms_next && syms_tail != p) {
		syms_tail->syms_next = p;
		syms_tail = p;
	}
}

static void revert_syms(struct dso *old_tail)
{
	struct dso *p, *next;
	/* Chop off the tail of the list of dsos that participate in
	 * the global symbol table, reverting them to RTLD_LOCAL. */
	for (p=old_tail; p; p=next) {
		next = p->syms_next;
		p->syms_next = 0;
	}
	syms_tail = old_tail;
}

static void do_mips_relocs(struct dso *p, size_t *got)
{
	size_t i, j, rel[2];
	unsigned char *base = p->base;
	i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);
	if (p==&ldso) {
		got += i;
	} else {
		while (i--) *got++ += (size_t)base;
	}
	j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
	i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
	Sym *sym = p->syms + j;
	rel[0] = (unsigned char *)got - base;
	for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {
		rel[1] = R_INFO(sym-p->syms, R_MIPS_JUMP_SLOT);
		do_relocs(p, rel, sizeof rel, 2);
	}
}

static void reloc_all(struct dso *p)
{
	size_t dyn[DYN_CNT];
	for (; p; p=p->next) {
		if (p->relocated) continue;
		decode_vec(p->dynv, dyn, DYN_CNT);
		if (NEED_MIPS_GOT_RELOCS)
			do_mips_relocs(p, laddr(p, dyn[DT_PLTGOT]));
		do_relocs(p, laddr(p, dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
			2+(dyn[DT_PLTREL]==DT_RELA));
		do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);
		do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);

		if (head != &ldso && p->relro_start != p->relro_end &&
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			mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_start, PROT_READ)
			&& errno != ENOSYS) {
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			error("Error relocating %s: RELRO protection failed: %m",
				p->name);
			if (runtime) longjmp(*rtld_fail, 1);
		}

		p->relocated = 1;
	}
}

static void kernel_mapped_dso(struct dso *p)
{
	size_t min_addr = -1, max_addr = 0, cnt;
	Phdr *ph = p->phdr;
	for (cnt = p->phnum; cnt--; ph = (void *)((char *)ph + p->phentsize)) {
		if (ph->p_type == PT_DYNAMIC) {
			p->dynv = laddr(p, ph->p_vaddr);
		} else if (ph->p_type == PT_GNU_RELRO) {
			p->relro_start = ph->p_vaddr & -PAGE_SIZE;
			p->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
		} else if (ph->p_type == PT_GNU_STACK) {
			if (!runtime && ph->p_memsz > __default_stacksize) {
				__default_stacksize =
					ph->p_memsz < DEFAULT_STACK_MAX ?
					ph->p_memsz : DEFAULT_STACK_MAX;
			}
		}
		if (ph->p_type != PT_LOAD) continue;
		if (ph->p_vaddr < min_addr)
			min_addr = ph->p_vaddr;
		if (ph->p_vaddr+ph->p_memsz > max_addr)
			max_addr = ph->p_vaddr+ph->p_memsz;
	}
	min_addr &= -PAGE_SIZE;
	max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
	p->map = p->base + min_addr;
	p->map_len = max_addr - min_addr;
	p->kernel_mapped = 1;
}

void __libc_exit_fini()
{
	struct dso *p;
	size_t dyn[DYN_CNT];
	int self = __pthread_self()->tid;

	/* Take both locks before setting shutting_down, so that
	 * either lock is sufficient to read its value. The lock
	 * order matches that in dlopen to avoid deadlock. */
	pthread_rwlock_wrlock(&lock);
	pthread_mutex_lock(&init_fini_lock);
	shutting_down = 1;
	pthread_rwlock_unlock(&lock);
	for (p=fini_head; p; p=p->fini_next) {
		while (p->ctor_visitor && p->ctor_visitor!=self)
			pthread_cond_wait(&ctor_cond, &init_fini_lock);
		if (!p->constructed) continue;
		decode_vec(p->dynv, dyn, DYN_CNT);
		if (dyn[0] & (1<<DT_FINI_ARRAY)) {
			size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
			size_t *fn = (size_t *)laddr(p, dyn[DT_FINI_ARRAY])+n;
			while (n--) ((void (*)(void))*--fn)();
		}
#ifndef NO_LEGACY_INITFINI
		if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
			fpaddr(p, dyn[DT_FINI])();
#endif
	}
}

static struct dso **queue_ctors(struct dso *dso)
{
	size_t cnt, qpos, spos, i;
	struct dso *p, **queue, **stack;

	if (ldd_mode) return 0;

	/* Bound on queue size is the total number of indirect deps.
	 * If a bfs deps list was built, we can use it. Otherwise,
	 * bound by the total number of DSOs, which is always safe and
	 * is reasonable we use it (for main app at startup). */
	if (dso->bfs_built) {
		for (cnt=0; dso->deps[cnt]; cnt++)
			dso->deps[cnt]->mark = 0;
		cnt++; /* self, not included in deps */
	} else {
		for (cnt=0, p=head; p; cnt++, p=p->next)
			p->mark = 0;
	}
	cnt++; /* termination slot */
	if (dso==head && cnt <= countof(builtin_ctor_queue))
		queue = builtin_ctor_queue;
	else
		queue = calloc(cnt, sizeof *queue);

	if (!queue) {
		error("Error allocating constructor queue: %m\n");
		if (runtime) longjmp(*rtld_fail, 1);
		return 0;
	}

	/* Opposite ends of the allocated buffer serve as an output queue
	 * and a working stack. Setup initial stack with just the argument
	 * dso and initial queue empty... */
	stack = queue;
	qpos = 0;
	spos = cnt;
	stack[--spos] = dso;
	dso->next_dep = 0;
	dso->mark = 1;

	/* Then perform pseudo-DFS sort, but ignoring circular deps. */
	while (spos<cnt) {
		p = stack[spos++];
		while (p->next_dep < p->ndeps_direct) {
			if (p->deps[p->next_dep]->mark) {
				p->next_dep++;
			} else {
				stack[--spos] = p;
				p = p->deps[p->next_dep];
				p->next_dep = 0;
				p->mark = 1;
			}
		}
		queue[qpos++] = p;
	}
	queue[qpos] = 0;
	for (i=0; i<qpos; i++) queue[i]->mark = 0;

	return queue;
}

static void do_init_fini(struct dso **queue)
{
	struct dso *p;
	size_t dyn[DYN_CNT], i;
	int self = __pthread_self()->tid;

	pthread_mutex_lock(&init_fini_lock);
	for (i=0; (p=queue[i]); i++) {
		while ((p->ctor_visitor && p->ctor_visitor!=self) || shutting_down)
			pthread_cond_wait(&ctor_cond, &init_fini_lock);
		if (p->ctor_visitor || p->constructed)
			continue;
		p->ctor_visitor = self;
		
		decode_vec(p->dynv, dyn, DYN_CNT);
		if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
			p->fini_next = fini_head;
			fini_head = p;
		}

		pthread_mutex_unlock(&init_fini_lock);

#ifndef NO_LEGACY_INITFINI
		if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
			fpaddr(p, dyn[DT_INIT])();
#endif
		if (dyn[0] & (1<<DT_INIT_ARRAY)) {
			size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
			size_t *fn = laddr(p, dyn[DT_INIT_ARRAY]);
			while (n--) ((void (*)(void))*fn++)();
		}

		pthread_mutex_lock(&init_fini_lock);
		p->ctor_visitor = 0;
		p->constructed = 1;
		pthread_cond_broadcast(&ctor_cond);
	}
	pthread_mutex_unlock(&init_fini_lock);
}

void __libc_start_init(void)
{
	do_init_fini(main_ctor_queue);
	if (!__malloc_replaced && main_ctor_queue != builtin_ctor_queue)
		free(main_ctor_queue);
	main_ctor_queue = 0;
}

static void dl_debug_state(void)
{
}

weak_alias(dl_debug_state, _dl_debug_state);

void __init_tls(size_t *auxv)
{
}

static void update_tls_size()
{
	libc.tls_cnt = tls_cnt;
	libc.tls_align = tls_align;
	libc.tls_size = ALIGN(
		(1+tls_cnt) * sizeof(void *) +
		tls_offset +
		sizeof(struct pthread) +
		tls_align * 2,
	tls_align);
}

static void install_new_tls(void)
{
	sigset_t set;
	pthread_t self = __pthread_self(), td;
	struct dso *dtv_provider = container_of(tls_tail, struct dso, tls);
	uintptr_t (*newdtv)[tls_cnt+1] = (void *)dtv_provider->new_dtv;
	struct dso *p;
	size_t i, j;
	size_t old_cnt = self->dtv[0];

	__block_app_sigs(&set);
	__tl_lock();
	/* Copy existing dtv contents from all existing threads. */
	for (i=0, td=self; !i || td!=self; i++, td=td->next) {
		memcpy(newdtv+i, td->dtv,
			(old_cnt+1)*sizeof(uintptr_t));
		newdtv[i][0] = tls_cnt;
	}
	/* Install new dtls into the enlarged, uninstalled dtv copies. */
	for (p=head; ; p=p->next) {
		if (p->tls_id <= old_cnt) continue;
		unsigned char *mem = p->new_tls;
		for (j=0; j<i; j++) {
			unsigned char *new = mem;
			new += ((uintptr_t)p->tls.image - (uintptr_t)mem)
				& (p->tls.align-1);
			memcpy(new, p->tls.image, p->tls.len);
			newdtv[j][p->tls_id] =
				(uintptr_t)new + DTP_OFFSET;
			mem += p->tls.size + p->tls.align;
		}
		if (p->tls_id == tls_cnt) break;
	}

	/* Broadcast barrier to ensure contents of new dtv is visible
	 * if the new dtv pointer is. The __membarrier function has a
	 * fallback emulation using signals for kernels that lack the
	 * feature at the syscall level. */

	__membarrier(MEMBARRIER_CMD_PRIVATE_EXPEDITED, 0);

	/* Install new dtv for each thread. */
	for (j=0, td=self; !j || td!=self; j++, td=td->next) {
		td->dtv = td->dtv_copy = newdtv[j];
	}

	__tl_unlock();
	__restore_sigs(&set);
}

/* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
 * following stage 2 and stage 3 functions via primitive symbolic lookup
 * since it does not have access to their addresses to begin with. */

/* Stage 2 of the dynamic linker is called after relative relocations 
 * have been processed. It can make function calls to static functions
 * and access string literals and static data, but cannot use extern
 * symbols. Its job is to perform symbolic relocations on the dynamic
 * linker itself, but some of the relocations performed may need to be
 * replaced later due to copy relocations in the main program. */

hidden void __dls2(unsigned char *base, size_t *sp)
{
	size_t *auxv;
	for (auxv=sp+1+*sp+1; *auxv; auxv++);
	auxv++;
	if (DL_FDPIC) {
		void *p1 = (void *)sp[-2];
		void *p2 = (void *)sp[-1];
		if (!p1) {
			size_t aux[AUX_CNT];
			decode_vec(auxv, aux, AUX_CNT);
			if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];
			else ldso.base = (void *)(aux[AT_PHDR] & -4096);
		}
		app_loadmap = p2 ? p1 : 0;
		ldso.loadmap = p2 ? p2 : p1;
		ldso.base = laddr(&ldso, 0);
	} else {
		ldso.base = base;
	}
	Ehdr *ehdr = (void *)ldso.base;
	ldso.name = ldso.shortname = "libc.so";
	ldso.phnum = ehdr->e_phnum;
	ldso.phdr = laddr(&ldso, ehdr->e_phoff);
	ldso.phentsize = ehdr->e_phentsize;
	kernel_mapped_dso(&ldso);
	decode_dyn(&ldso);

	if (DL_FDPIC) makefuncdescs(&ldso);

	/* Prepare storage for to save clobbered REL addends so they
	 * can be reused in stage 3. There should be very few. If
	 * something goes wrong and there are a huge number, abort
	 * instead of risking stack overflow. */
	size_t dyn[DYN_CNT];
	decode_vec(ldso.dynv, dyn, DYN_CNT);
	size_t *rel = laddr(&ldso, dyn[DT_REL]);
	size_t rel_size = dyn[DT_RELSZ];
	size_t symbolic_rel_cnt = 0;
	apply_addends_to = rel;
	for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t))
		if (!IS_RELATIVE(rel[1], ldso.syms)) symbolic_rel_cnt++;
	if (symbolic_rel_cnt >= ADDEND_LIMIT) a_crash();
	size_t addends[symbolic_rel_cnt+1];
	saved_addends = addends;

	head = &ldso;
	reloc_all(&ldso);

	ldso.relocated = 0;

	/* Call dynamic linker stage-2b, __dls2b, looking it up
	 * symbolically as a barrier against moving the address
	 * load across the above relocation processing. */
	struct symdef dls2b_def = find_sym(&ldso, "__dls2b", 0);
	if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls2b_def.sym-ldso.syms])(sp, auxv);
	else ((stage3_func)laddr(&ldso, dls2b_def.sym->st_value))(sp, auxv);
}

/* Stage 2b sets up a valid thread pointer, which requires relocations
 * completed in stage 2, and on which stage 3 is permitted to depend.
 * This is done as a separate stage, with symbolic lookup as a barrier,
 * so that loads of the thread pointer and &errno can be pure/const and
 * thereby hoistable. */

void __dls2b(size_t *sp, size_t *auxv)
{
	/* Setup early thread pointer in builtin_tls for ldso/libc itself to
	 * use during dynamic linking. If possible it will also serve as the
	 * thread pointer at runtime. */
	search_vec(auxv, &__hwcap, AT_HWCAP);
	libc.auxv = auxv;
	libc.tls_size = sizeof builtin_tls;
	libc.tls_align = tls_align;
	if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
		a_crash();
	}

	struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
	if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp, auxv);
	else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp, auxv);
}

/* Stage 3 of the dynamic linker is called with the dynamic linker/libc
 * fully functional. Its job is to load (if not already loaded) and
 * process dependencies and relocations for the main application and
 * transfer control to its entry point. */

void __dls3(size_t *sp, size_t *auxv)
{
	static struct dso app, vdso;
	size_t aux[AUX_CNT];
	size_t i;
	char *env_preload=0;
	char *replace_argv0=0;
	size_t vdso_base;
	int argc = *sp;
	char **argv = (void *)(sp+1);
	char **argv_orig = argv;
	char **envp = argv+argc+1;

	/* Find aux vector just past environ[] and use it to initialize
	 * global data that may be needed before we can make syscalls. */
	__environ = envp;
	decode_vec(auxv, aux, AUX_CNT);
	search_vec(auxv, &__sysinfo, AT_SYSINFO);
	__pthread_self()->sysinfo = __sysinfo;
	libc.page_size = aux[AT_PAGESZ];
	libc.secure = ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
		|| aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]);

	/* Only trust user/env if kernel says we're not suid/sgid */
	if (!libc.secure) {
		env_path = getenv("LD_LIBRARY_PATH");
		env_preload = getenv("LD_PRELOAD");
	}

	/* If the main program was already loaded by the kernel,
	 * AT_PHDR will point to some location other than the dynamic
	 * linker's program headers. */
	if (aux[AT_PHDR] != (size_t)ldso.phdr) {
		size_t interp_off = 0;
		size_t tls_image = 0;
		/* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
		Phdr *phdr = app.phdr = (void *)aux[AT_PHDR];
		app.phnum = aux[AT_PHNUM];
		app.phentsize = aux[AT_PHENT];
		for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
			if (phdr->p_type == PT_PHDR)
				app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
			else if (phdr->p_type == PT_INTERP)
				interp_off = (size_t)phdr->p_vaddr;
			else if (phdr->p_type == PT_TLS) {
				tls_image = phdr->p_vaddr;
				app.tls.len = phdr->p_filesz;
				app.tls.size = phdr->p_memsz;
				app.tls.align = phdr->p_align;
			}
		}
		if (DL_FDPIC) app.loadmap = app_loadmap;
		if (app.tls.size) app.tls.image = laddr(&app, tls_image);
		if (interp_off) ldso.name = laddr(&app, interp_off);
		if ((aux[0] & (1UL<<AT_EXECFN))
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			&& strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
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			app.name = (char *)aux[AT_EXECFN];
		else
			app.name = argv[0];
		kernel_mapped_dso(&app);
	} else {
		int fd;
		char *ldname = argv[0];
		size_t l = strlen(ldname);
		if (l >= 3 && !strcmp(ldname+l-3, "ldd")) ldd_mode = 1;
		argv++;
		while (argv[0] && argv[0][0]=='-' && argv[0][1]=='-') {
			char *opt = argv[0]+2;
			*argv++ = (void *)-1;
			if (!*opt) {
				break;
			} else if (!memcmp(opt, "list", 5)) {
				ldd_mode = 1;
			} else if (!memcmp(opt, "library-path", 12)) {
				if (opt[12]=='=') env_path = opt+13;
				else if (opt[12]) *argv = 0;
				else if (*argv) env_path = *argv++;
			} else if (!memcmp(opt, "preload", 7)) {
				if (opt[7]=='=') env_preload = opt+8;
				else if (opt[7]) *argv = 0;
				else if (*argv) env_preload = *argv++;
			} else if (!memcmp(opt, "argv0", 5)) {
				if (opt[5]=='=') replace_argv0 = opt+6;
				else if (opt[5]) *argv = 0;
				else if (*argv) replace_argv0 = *argv++;
			} else {
				argv[0] = 0;
			}
		}
		argv[-1] = (void *)(argc - (argv-argv_orig));
		if (!argv[0]) {
			dprintf(2, "musl libc (" LDSO_ARCH ")\n"
				"Version %s\n"
				"Dynamic Program Loader\n"
				"Usage: %s [options] [--] pathname%s\n",
				__libc_version, ldname,
				ldd_mode ? "" : " [args]");
			_exit(1);
		}
		fd = open(argv[0], O_RDONLY);
		if (fd < 0) {
			dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
			_exit(1);
		}
		Ehdr *ehdr = (void *)map_library(fd, &app);
		if (!ehdr) {
			dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
			_exit(1);
		}
		close(fd);
		ldso.name = ldname;
		app.name = argv[0];
		aux[AT_ENTRY] = (size_t)laddr(&app, ehdr->e_entry);
		/* Find the name that would have been used for the dynamic
		 * linker had ldd not taken its place. */
		if (ldd_mode) {
			for (i=0; i<app.phnum; i++) {
				if (app.phdr[i].p_type == PT_INTERP)
					ldso.name = laddr(&app, app.phdr[i].p_vaddr);
			}
			dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
		}
	}
	if (app.tls.size) {
		libc.tls_head = tls_tail = &app.tls;
		app.tls_id = tls_cnt = 1;
#ifdef TLS_ABOVE_TP
		app.tls.offset = GAP_ABOVE_TP;
		app.tls.offset += (-GAP_ABOVE_TP + (uintptr_t)app.tls.image)
			& (app.tls.align-1);
		tls_offset = app.tls.offset + app.tls.size;
#else
		tls_offset = app.tls.offset = app.tls.size
			+ ( -((uintptr_t)app.tls.image + app.tls.size)
			& (app.tls.align-1) );
#endif
		tls_align = MAXP2(tls_align, app.tls.align);
	}
	decode_dyn(&app);
	if (DL_FDPIC) {
		makefuncdescs(&app);
		if (!app.loadmap) {
			app.loadmap = (void *)&app_dummy_loadmap;
			app.loadmap->nsegs = 1;
			app.loadmap->segs[0].addr = (size_t)app.map;
			app.loadmap->segs[0].p_vaddr = (size_t)app.map
				- (size_t)app.base;
			app.loadmap->segs[0].p_memsz = app.map_len;
		}
		argv[-3] = (void *)app.loadmap;
	}

	/* Initial dso chain consists only of the app. */
	head = tail = syms_tail = &app;

	/* Donate unused parts of app and library mapping to malloc */
	reclaim_gaps(&app);
	reclaim_gaps(&ldso);

	/* Load preload/needed libraries, add symbols to global namespace. */
	ldso.deps = (struct dso **)no_deps;
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	/* Init g_is_asan */
	g_is_asan = false;
	LD_LOGI("__dls3 ldso.name:%s.\n", ldso.name);
	/* Through ldso Name to judge whether the Asan function is enabled */
	if (strstr(ldso.name, "-asan")) {
		g_is_asan = true;
		LD_LOGI("__dls3 g_is_asan is true.\n");
	}
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	/* Init all namespaces by config file. there is a default namespace always*/
	init_namespace(&app);
	if (env_preload) load_preload(env_preload, get_default_ns());
 	load_deps(&app, get_default_ns());
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	for (struct dso *p=head; p; p=p->next)
		add_syms(p);

	/* Attach to vdso, if provided by the kernel, last so that it does
	 * not become part of the global namespace.  */
	if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR) && vdso_base) {
		Ehdr *ehdr = (void *)vdso_base;
		Phdr *phdr = vdso.phdr = (void *)(vdso_base + ehdr->e_phoff);
		vdso.phnum = ehdr->e_phnum;
		vdso.phentsize = ehdr->e_phentsize;
		for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
			if (phdr->p_type == PT_DYNAMIC)
				vdso.dynv = (void *)(vdso_base + phdr->p_offset);
			if (phdr->p_type == PT_LOAD)
				vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
		}
		vdso.name = "";
		vdso.shortname = "linux-gate.so.1";
		vdso.relocated = 1;
		vdso.deps = (struct dso **)no_deps;
		decode_dyn(&vdso);
		vdso.prev = tail;
		tail->next = &vdso;
		tail = &vdso;
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		vdso.namespace = get_default_ns();
		ns_add_dso(vdso.namespace, &vdso);
2179 2180 2181 2182 2183 2184 2185 2186 2187 2188 2189 2190 2191 2192 2193 2194 2195 2196 2197 2198 2199 2200 2201 2202 2203 2204 2205 2206 2207 2208 2209 2210 2211 2212 2213 2214 2215 2216 2217 2218 2219 2220 2221 2222 2223 2224 2225 2226 2227 2228 2229 2230 2231 2232 2233 2234 2235 2236 2237 2238 2239 2240 2241 2242 2243 2244 2245 2246 2247 2248 2249 2250 2251 2252 2253 2254 2255 2256 2257 2258 2259 2260 2261 2262 2263 2264 2265 2266 2267 2268 2269 2270 2271 2272 2273 2274 2275 2276 2277 2278 2279 2280 2281 2282 2283 2284
	}

	for (i=0; app.dynv[i]; i+=2) {
		if (!DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG)
			app.dynv[i+1] = (size_t)&debug;
		if (DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG_INDIRECT) {
			size_t *ptr = (size_t *) app.dynv[i+1];
			*ptr = (size_t)&debug;
		}
	}

	/* This must be done before final relocations, since it calls
	 * malloc, which may be provided by the application. Calling any
	 * application code prior to the jump to its entry point is not
	 * valid in our model and does not work with FDPIC, where there
	 * are additional relocation-like fixups that only the entry point
	 * code can see to perform. */
	main_ctor_queue = queue_ctors(&app);

	/* Initial TLS must also be allocated before final relocations
	 * might result in calloc being a call to application code. */
	update_tls_size();
	void *initial_tls = builtin_tls;
	if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
		initial_tls = calloc(libc.tls_size, 1);
		if (!initial_tls) {
			dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
				argv[0], libc.tls_size);
			_exit(127);
		}
	}
	static_tls_cnt = tls_cnt;

	/* The main program must be relocated LAST since it may contain
	 * copy relocations which depend on libraries' relocations. */
	reloc_all(app.next);
	reloc_all(&app);

	/* Actual copying to new TLS needs to happen after relocations,
	 * since the TLS images might have contained relocated addresses. */
	if (initial_tls != builtin_tls) {
		if (__init_tp(__copy_tls(initial_tls)) < 0) {
			a_crash();
		}
	} else {
		size_t tmp_tls_size = libc.tls_size;
		pthread_t self = __pthread_self();
		/* Temporarily set the tls size to the full size of
		 * builtin_tls so that __copy_tls will use the same layout
		 * as it did for before. Then check, just to be safe. */
		libc.tls_size = sizeof builtin_tls;
		if (__copy_tls((void*)builtin_tls) != self) a_crash();
		libc.tls_size = tmp_tls_size;
	}

	if (ldso_fail) _exit(127);
	if (ldd_mode) _exit(0);

	/* Determine if malloc was interposed by a replacement implementation
	 * so that calloc and the memalign family can harden against the
	 * possibility of incomplete replacement. */
	if (find_sym(head, "malloc", 1).dso != &ldso)
		__malloc_replaced = 1;

	/* Switch to runtime mode: any further failures in the dynamic
	 * linker are a reportable failure rather than a fatal startup
	 * error. */
	runtime = 1;

	debug.ver = 1;
	debug.bp = dl_debug_state;
	debug.head = head;
	debug.base = ldso.base;
	debug.state = 0;
	_dl_debug_state();

	if (replace_argv0) argv[0] = replace_argv0;

	errno = 0;

	CRTJMP((void *)aux[AT_ENTRY], argv-1);
	for(;;);
}

static void prepare_lazy(struct dso *p)
{
	size_t dyn[DYN_CNT], n, flags1=0;
	decode_vec(p->dynv, dyn, DYN_CNT);
	search_vec(p->dynv, &flags1, DT_FLAGS_1);
	if (dyn[DT_BIND_NOW] || (dyn[DT_FLAGS] & DF_BIND_NOW) || (flags1 & DF_1_NOW))
		return;
	n = dyn[DT_RELSZ]/2 + dyn[DT_RELASZ]/3 + dyn[DT_PLTRELSZ]/2 + 1;
	if (NEED_MIPS_GOT_RELOCS) {
		size_t j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
		size_t i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
		n += i-j;
	}
	p->lazy = calloc(n, 3*sizeof(size_t));
	if (!p->lazy) {
		error("Error preparing lazy relocation for %s: %m", p->name);
		longjmp(*rtld_fail, 1);
	}
	p->lazy_next = lazy_head;
	lazy_head = p;
}

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/* add namespace function */
static void *dlopen_impl(const char *file, int mode, const char *namespace, const void *caller_addr)
2287 2288 2289 2290 2291 2292 2293 2294
{
	struct dso *volatile p, *orig_tail, *orig_syms_tail, *orig_lazy_head, *next;
	struct tls_module *orig_tls_tail;
	size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
	size_t i;
	int cs;
	jmp_buf jb;
	struct dso **volatile ctor_queue = 0;
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	ns_t *ns;
	struct dso *caller;
2297

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	if (!file) {
		LD_LOGD("dlopen_impl file is null,return head.\n");
		return head;
	}
2302 2303 2304 2305

	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
	pthread_rwlock_wrlock(&lock);
	__inhibit_ptc();
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	/* When namespace does not exist, use caller's namespce
	 * and when caller does not exist, use default namespce. */
	caller = (struct dso *)addr2dso((size_t)caller_addr);
	ns = find_ns_by_name(namespace);
	if (!ns) ns = ((caller && caller->namespace) ? caller->namespace : get_default_ns());
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	p = 0;
	if (shutting_down) {
		error("Cannot dlopen while program is exiting.");
		goto end;
	}
	orig_tls_tail = tls_tail;
	orig_tls_cnt = tls_cnt;
	orig_tls_offset = tls_offset;
	orig_tls_align = tls_align;
	orig_lazy_head = lazy_head;
	orig_syms_tail = syms_tail;
	orig_tail = tail;
	noload = mode & RTLD_NOLOAD;

	rtld_fail = &jb;
	if (setjmp(*rtld_fail)) {
		/* Clean up anything new that was (partially) loaded */
		revert_syms(orig_syms_tail);
		for (p=orig_tail->next; p; p=next) {
			next = p->next;
			while (p->td_index) {
				void *tmp = p->td_index->next;
				free(p->td_index);
				p->td_index = tmp;
			}
			free(p->funcdescs);
			if (p->rpath != p->rpath_orig)
				free(p->rpath);
			free(p->deps);
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			dlclose_ns(p);
2343 2344 2345 2346 2347 2348 2349 2350 2351 2352 2353 2354 2355 2356 2357 2358
			unmap_library(p);
			free(p);
		}
		free(ctor_queue);
		ctor_queue = 0;
		if (!orig_tls_tail) libc.tls_head = 0;
		tls_tail = orig_tls_tail;
		if (tls_tail) tls_tail->next = 0;
		tls_cnt = orig_tls_cnt;
		tls_offset = orig_tls_offset;
		tls_align = orig_tls_align;
		lazy_head = orig_lazy_head;
		tail = orig_tail;
		tail->next = 0;
		p = 0;
		goto end;
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	} else p = load_library(file, head, ns, true);
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	if (!p) {
		error(noload ?
			"Library %s is not already loaded" :
			"Error loading shared library %s: %m",
			file);
		goto end;
	}

	/* First load handling */
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	load_deps(p, ns);
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	extend_bfs_deps(p);
	pthread_mutex_lock(&init_fini_lock);
	if (!p->constructed) ctor_queue = queue_ctors(p);
	pthread_mutex_unlock(&init_fini_lock);
	if (!p->relocated && (mode & RTLD_LAZY)) {
		prepare_lazy(p);
		for (i=0; p->deps[i]; i++)
			if (!p->deps[i]->relocated)
				prepare_lazy(p->deps[i]);
	}
	if (!p->relocated || (mode & RTLD_GLOBAL)) {
		/* Make new symbols global, at least temporarily, so we can do
		 * relocations. If not RTLD_GLOBAL, this is reverted below. */
		add_syms(p);
		for (i=0; p->deps[i]; i++)
			add_syms(p->deps[i]);
	}
	if (!p->relocated) {
		reloc_all(p);
	}

	/* If RTLD_GLOBAL was not specified, undo any new additions
	 * to the global symbol table. This is a nop if the library was
	 * previously loaded and already global. */
	if (!(mode & RTLD_GLOBAL))
		revert_syms(orig_syms_tail);

	/* Processing of deferred lazy relocations must not happen until
	 * the new libraries are committed; otherwise we could end up with
	 * relocations resolved to symbol definitions that get removed. */
	redo_lazy_relocs();

	if (mode & RTLD_NODELETE) {
		p->flags |= DSO_FLAGS_NODELETE;
	}

	update_tls_size();
	if (tls_cnt != orig_tls_cnt)
		install_new_tls();
	_dl_debug_state();
	orig_tail = tail;
end:
	__release_ptc();
	if (p) gencnt++;
	pthread_rwlock_unlock(&lock);
	if (ctor_queue) {
		do_init_fini(ctor_queue);
		free(ctor_queue);
	}
	pthread_setcancelstate(cs, 0);
	return p;
}

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void *dlopen(const char *file, int mode)
{
	const void *caller_addr = __builtin_return_address(0);
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	LD_LOGI("dlopen file:%s, mode:%d ,caller_addr:%p .\n", file, mode, caller_addr);
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	return dlopen_impl(file, mode, NULL, caller_addr);
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}

void dlns_init(Dl_namespace *dlns, const char *name)
{
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	if (!dlns) {
		LD_LOGW("dlns_init dlns is null.\n");
		return;
	}
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	if (!name) {
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		LD_LOGE("dlns_init name is null.\n");
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		dlns->name[0] = 0;
		return;
	}
	snprintf(dlns->name, sizeof dlns->name, name);
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	LD_LOGI("dlns_init dlns->name:%s .\n", dlns->name);
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}

void *dlopen_ns(Dl_namespace *dlns, const char *file, int mode)
{
	const void *caller_addr = __builtin_return_address(0);
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	LD_LOGI("dlopen_ns file:%s, mode:%d , caller_addr:%p , dlns->name:%s.\n", file, mode, caller_addr, dlns->name);
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	return dlopen_impl(file, mode, dlns->name, caller_addr);
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}

int dlns_create(Dl_namespace *dlns, const char *lib_path)
{
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	if (!dlns) {
		LD_LOGW("dlns_create dlns is null.\n");
		return EINVAL;
	}
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	ns_t *ns;

	pthread_rwlock_wrlock(&lock);
	ns = find_ns_by_name(dlns->name);
	if (ns) {
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		LD_LOGE("dlns_create ns is exist.\n");
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		pthread_rwlock_unlock(&lock);
		return EEXIST;
	}
	ns = ns_alloc();
	if (!ns) {
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		LD_LOGE("dlns_create no memery.\n");
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		pthread_rwlock_unlock(&lock);
		return ENOMEM;
	}
	ns_set_name(ns, dlns->name);
	ns_add_dso(ns, get_default_ns()->ns_dsos->dsos[0]); /* add main app to this namespace*/
	nslist_add_ns(ns); /* add ns to list*/
	ns_set_lib_paths(ns, lib_path);
	ns_add_inherit(ns, get_default_ns(), NULL);
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	LD_LOGI("dlns_create :"
			"ns: %p ,"
			"ns_name: %s ,"
			"separated:%d ,"
			"lib_paths:%s ",
			ns, ns->ns_name, ns->separated, ns->lib_paths);
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	pthread_rwlock_unlock(&lock);

	return 0;
}

int dlns_inherit(Dl_namespace *dlns, Dl_namespace *inherited, const char *shared_libs)
{
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	if (!dlns || !inherited) {
		LD_LOGW("dlns_inherit dlns or inherited is null.\n");
		return EINVAL;
	}
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	pthread_rwlock_wrlock(&lock);
	ns_t* ns = find_ns_by_name(dlns->name);
	ns_t* ns_inherited = find_ns_by_name(inherited->name);
	if (!ns || !ns_inherited) {
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		LD_LOGW("dlns_inherit ns or ns_inherited is not found.\n");
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		pthread_rwlock_unlock(&lock);
		return ENOKEY;
	}
	ns_add_inherit(ns, ns_inherited, shared_libs);
	pthread_rwlock_unlock(&lock);

	return 0;
}

static void dlclose_ns(struct dso *p)
{
	if (!p) return;
	ns_t * ns = p->namespace;
	if (!ns||!ns->ns_dsos) return;
	for (size_t i=0; i<ns->ns_dsos->num; i++) {
		if (p == ns->ns_dsos->dsos[i]) {
			for (size_t j=i+1; j<ns->ns_dsos->num; j++) {
				ns->ns_dsos->dsos[j-1] = ns->ns_dsos->dsos[j];
			}
			ns->ns_dsos->num--;
			return;
		}
	}
}

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hidden int __dl_invalid_handle(void *h)
{
	struct dso *p;
	for (p=head; p; p=p->next) if (h==p) return 0;
	error("Invalid library handle %p", (void *)h);
	return 1;
}

static void *addr2dso(size_t a)
{
	struct dso *p;
	size_t i;
	if (DL_FDPIC) for (p=head; p; p=p->next) {
		i = count_syms(p);
		if (a-(size_t)p->funcdescs < i*sizeof(*p->funcdescs))
			return p;
	}
	for (p=head; p; p=p->next) {
		if (DL_FDPIC && p->loadmap) {
			for (i=0; i<p->loadmap->nsegs; i++) {
				if (a-p->loadmap->segs[i].p_vaddr
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					< p->loadmap->segs[i].p_memsz)
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					return p;
			}
		} else {
			Phdr *ph = p->phdr;
			size_t phcnt = p->phnum;
			size_t entsz = p->phentsize;
			size_t base = (size_t)p->base;
			for (; phcnt--; ph=(void *)((char *)ph+entsz)) {
				if (ph->p_type != PT_LOAD) continue;
				if (a-base-ph->p_vaddr < ph->p_memsz)
					return p;
			}
			if (a-(size_t)p->map < p->map_len)
				return 0;
		}
	}
	return 0;
}

static void *do_dlsym(struct dso *p, const char *s, void *ra)
{
	int use_deps = 0;
	if (p == head || p == RTLD_DEFAULT) {
		p = head;
	} else if (p == RTLD_NEXT) {
		p = addr2dso((size_t)ra);
		if (!p) p=head;
		p = p->next;
	} else if (__dl_invalid_handle(p)) {
		return 0;
	} else
		use_deps = 1;
	struct symdef def = find_sym2(p, s, 0, use_deps);
	if (!def.sym) {
		error("Symbol not found: %s", s);
		return 0;
	}
	if ((def.sym->st_info&0xf) == STT_TLS)
		return __tls_get_addr((tls_mod_off_t []){def.dso->tls_id, def.sym->st_value-DTP_OFFSET});
	if (DL_FDPIC && (def.sym->st_info&0xf) == STT_FUNC)
		return def.dso->funcdescs + (def.sym - def.dso->syms);
	return laddr(def.dso, def.sym->st_value);
}

static int do_dlclose(struct dso *p)
{
	int old;
	size_t n;
	struct dso *d;

	if (__dl_invalid_handle(p))
		return -1;

	if (!p->by_dlopen) {
		error("Library %s is not loaded by dlopen", p->name);
		return -1;
	}

	/* dso is marked  as RTLD_NODELETE library, do nothing here. */
	if ((p->flags & DSO_FLAGS_NODELETE) != 0) {
		return 0;
	}

	old = a_fetch_add(&p->nr_dlopen, -1);
	if (old > 1)
		return 0;

	/* call destructors if needed */
	if (p->constructed) {
		size_t dyn[DYN_CNT];
		decode_vec(p->dynv, dyn, DYN_CNT);
		if (dyn[0] & (1<<DT_FINI_ARRAY)) {
			n = dyn[DT_FINI_ARRAYSZ] / sizeof(size_t);
			size_t *fn = (size_t *)laddr(p, dyn[DT_FINI_ARRAY]) + n;
			while (n--)
				((void (*)(void))*--fn)();
		}
		p->constructed = 0;
	}

	/* remove dso symbols from global list */
	if (p->syms_next) {
		for (d = head; d->syms_next != p; d = d->syms_next)
			; /* NOP */
		d->syms_next = p->syms_next;
	} else if (p == syms_tail) {
		for (d = head; d->syms_next != p; d = d->syms_next)
			; /* NOP */
		d->syms_next = NULL;
		syms_tail = d;
	}

	/* remove dso from lazy list if needed */
	if (p == lazy_head) {
		lazy_head = p->lazy_next;
	} else if (p->lazy_next) {
		for (d = lazy_head; d->lazy_next != p; d = d->lazy_next)
			; /* NOP */
		d->lazy_next = p->lazy_next;
	}

	/* remove dso from fini list */
	if (p == fini_head) {
		fini_head = p->fini_next;
	} else if (p->fini_next) {
		for (d = fini_head; d->fini_next != p; d = d->fini_next)
			; /* NOP */
		d->fini_next = p->fini_next;
	}

	/* remove dso from global dso list */
	if (p == tail) {
		tail = p->prev;
		tail->next = NULL;
	} else {
		p->next->prev = p->prev;
		p->prev->next = p->next;
	}

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	/* remove dso from namespace */
	dlclose_ns(p);
	
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	if (p->lazy != NULL)
		free(p->lazy);
	if (p->deps != no_deps)
		free(p->deps);
	unmap_library(p);
	free(p);

	return 0;
}

hidden int __dlclose(void *p)
{
	int rc;
	pthread_rwlock_wrlock(&lock);
	__inhibit_ptc();
	rc = do_dlclose(p);
	__release_ptc();
	pthread_rwlock_unlock(&lock);
	return rc;
}

int dladdr(const void *addr_arg, Dl_info *info)
{
	size_t addr = (size_t)addr_arg;
	struct dso *p;
	Sym *sym, *bestsym;
	uint32_t nsym;
	char *strings;
	size_t best = 0;
	size_t besterr = -1;

	pthread_rwlock_rdlock(&lock);
	p = addr2dso(addr);
	pthread_rwlock_unlock(&lock);

	if (!p) return 0;

	sym = p->syms;
	strings = p->strings;
	nsym = count_syms(p);

	if (DL_FDPIC) {
		size_t idx = (addr-(size_t)p->funcdescs)
			/ sizeof(*p->funcdescs);
		if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
			best = (size_t)(p->funcdescs + idx);
			bestsym = sym + idx;
			besterr = 0;
		}
	}

	if (!best) for (; nsym; nsym--, sym++) {
		if (sym->st_value
		 && (1<<(sym->st_info&0xf) & OK_TYPES)
		 && (1<<(sym->st_info>>4) & OK_BINDS)) {
			size_t symaddr = (size_t)laddr(p, sym->st_value);
			if (symaddr > addr || symaddr <= best)
				continue;
			best = symaddr;
			bestsym = sym;
			besterr = addr - symaddr;
			if (addr == symaddr)
				break;
		}
	}

	if (best && besterr > bestsym->st_size-1) {
		best = 0;
		bestsym = 0;
	}

	info->dli_fname = p->name;
	info->dli_fbase = p->map;

	if (!best) {
		info->dli_sname = 0;
		info->dli_saddr = 0;
		return 1;
	}

	if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
		best = (size_t)(p->funcdescs + (bestsym - p->syms));
	info->dli_sname = strings + bestsym->st_name;
	info->dli_saddr = (void *)best;

	return 1;
}

hidden void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
{
	void *res;
	pthread_rwlock_rdlock(&lock);
	res = do_dlsym(p, s, ra);
	pthread_rwlock_unlock(&lock);
	return res;
}

hidden void *__dlsym_redir_time64(void *restrict p, const char *restrict s, void *restrict ra)
{
#if _REDIR_TIME64
	const char *suffix, *suffix2 = "";
	char redir[36];

	/* Map the symbol name to a time64 version of itself according to the
	 * pattern used for naming the redirected time64 symbols. */
	size_t l = strnlen(s, sizeof redir);
	if (l<4 || l==sizeof redir) goto no_redir;
	if (s[l-2]=='_' && s[l-1]=='r') {
		l -= 2;
		suffix2 = s+l;
	}
	if (l<4) goto no_redir;
	if (!strcmp(s+l-4, "time")) suffix = "64";
	else suffix = "_time64";

	/* Use the presence of the remapped symbol name in libc to determine
	 * whether it's one that requires time64 redirection; replace if so. */
	snprintf(redir, sizeof redir, "__%.*s%s%s", (int)l, s, suffix, suffix2);
	if (find_sym(&ldso, redir, 1).sym) s = redir;
no_redir:
#endif
	return __dlsym(p, s, ra);
}

int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
{
	struct dso *current;
	struct dl_phdr_info info;
	int ret = 0;
	for(current = head; current;) {
		info.dlpi_addr      = (uintptr_t)current->base;
		info.dlpi_name      = current->name;
		info.dlpi_phdr      = current->phdr;
		info.dlpi_phnum     = current->phnum;
		info.dlpi_adds      = gencnt;
		info.dlpi_subs      = 0;
		info.dlpi_tls_modid = current->tls_id;
		info.dlpi_tls_data  = current->tls.image;

		ret = (callback)(&info, sizeof (info), data);

		if (ret != 0) break;

		pthread_rwlock_rdlock(&lock);
		current = current->next;
		pthread_rwlock_unlock(&lock);
	}
	return ret;
}

static void error(const char *fmt, ...)
{
	va_list ap;
	va_start(ap, fmt);
	if (!runtime) {
		vdprintf(2, fmt, ap);
		dprintf(2, "\n");
		ldso_fail = 1;
		va_end(ap);
		return;
	}
	__dl_vseterr(fmt, ap);
	va_end(ap);
}
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int dlns_set_namespace_lib_path(const char * name, const char * lib_path)
{
	if (!name || !lib_path) {
		LD_LOGW("dlns_set_namespace_lib_path name or lib_path is null.\n");
		return EINVAL;
	}

	pthread_rwlock_wrlock(&lock);
	ns_t* ns = find_ns_by_name(name);
	if (!ns) {
		pthread_rwlock_unlock(&lock);
		LD_LOGW("dlns_set_namespace_lib_path fail, input ns name : [%s] is not found.\n", name);
		return ENOKEY;
	}

	ns_set_lib_paths(ns, lib_path);
	pthread_rwlock_unlock(&lock);
	return 0;
}

int dlns_set_namespace_separated(const char * name, const bool separated)
{
	if (!name) {
		LD_LOGW("dlns_set_namespace_separated name  is null.\n");
		return EINVAL;
	}

	pthread_rwlock_wrlock(&lock);
	ns_t* ns = find_ns_by_name(name);
	if (!ns) {
		pthread_rwlock_unlock(&lock);
		LD_LOGW("dlns_set_namespace_separated fail, input ns name : [%s] is not found.\n", name);
		return ENOKEY;
	}

	ns_set_separated(ns, separated);
	pthread_rwlock_unlock(&lock);
	return 0;
}

int dlns_set_namespace_permitted_paths(const char * name, const char * permitted_paths)
{
	if (!name || !permitted_paths) {
		LD_LOGW("dlns_set_namespace_permitted_paths name or permitted_paths is null.\n");
		return EINVAL;
	}

	pthread_rwlock_wrlock(&lock);
	ns_t* ns = find_ns_by_name(name);
	if (!ns) {
		pthread_rwlock_unlock(&lock);
		LD_LOGW("dlns_set_namespace_permitted_paths fail, input ns name : [%s] is not found.\n", name);
		return ENOKEY;
	}

	ns_set_permitted_paths(ns, permitted_paths);
	pthread_rwlock_unlock(&lock);
	return 0;
}

int dlns_set_namespace_allowed_libs(const char * name, const char * allowed_libs)
{
	if (!name || !allowed_libs) {
		LD_LOGW("dlns_set_namespace_allowed_libs name or allowed_libs is null.\n");
		return EINVAL;
	}

	pthread_rwlock_wrlock(&lock);
	ns_t* ns = find_ns_by_name(name);
	if (!ns) {
		pthread_rwlock_unlock(&lock);
		LD_LOGW("dlns_set_namespace_allowed_libs fail, input ns name : [%s] is not found.\n", name);
		return ENOKEY;
	}

	ns_set_allowed_libs(ns, allowed_libs);
	pthread_rwlock_unlock(&lock);
	return 0;
}

int handle_asan_path_open(int fd, const char *name, ns_t *namespace, char *buf)
{
	LD_LOGD("handle_asan_path_open fd:%d, name:%s , namespace:%p , buf:%s.\n", fd, name, namespace, buf);
	int fd_tmp = fd;
	if (fd == -1 && (namespace->asan_lib_paths || namespace->lib_paths)) {
		if (namespace->lib_paths && namespace->asan_lib_paths) {
			size_t newlen = strlen(namespace->asan_lib_paths) + strlen(namespace->lib_paths) + 2;
			char *new_lib_paths = malloc(newlen);
			memset(new_lib_paths, 0, newlen);
			strcpy(new_lib_paths, namespace->asan_lib_paths);
			strcat(new_lib_paths, ":");
			strcat(new_lib_paths, namespace->lib_paths);
			fd_tmp = path_open(name, new_lib_paths, buf, sizeof buf);
			LD_LOGD("handle_asan_path_open path_open new_lib_paths:%s ,fd: %d.\n", new_lib_paths, fd_tmp);
			free(new_lib_paths);
		} else if (namespace->asan_lib_paths) {
			fd_tmp = path_open(name, namespace->asan_lib_paths, buf, sizeof buf);
			LD_LOGD("handle_asan_path_open path_open asan_lib_paths:%s ,fd: %d.\n", namespace->asan_lib_paths, fd_tmp);
		} else {
			fd_tmp = path_open(name, namespace->lib_paths, buf, sizeof buf);
			LD_LOGD("handle_asan_path_open path_open lib_paths:%s ,fd: %d.\n", namespace->lib_paths, fd_tmp);
		}
	}
	return fd_tmp;
}