ARCH_SRCS = $(wildcard $(srcdir)/src/*/$(ARCH)/*.[csS])
ARCH_OBJS = $(patsubst $(srcdir)/%,%.o,$(basename $(ARCH_SRCS)))
REPLACED_OBJS = $(sort $(subst /$(ARCH)/,/,$(ARCH_OBJS)))
+LDSO_SRCS = $(sort $(wildcard $(srcdir)/ldso/*.c))
+LDSO_OBJS = $(patsubst $(srcdir)/%,obj/%.lo,$(basename $(LDSO_SRCS)))
OBJS = $(addprefix obj/, $(filter-out $(REPLACED_OBJS), $(sort $(BASE_OBJS) $(ARCH_OBJS))))
LOBJS = $(OBJS:.o=.lo)
GENH = obj/include/bits/alltypes.h
all: $(ALL_LIBS) $(ALL_TOOLS)
-OBJ_DIRS = $(sort $(patsubst %/,%,$(dir $(ALL_LIBS) $(ALL_TOOLS) $(OBJS) $(GENH) $(GENH_INT))) $(addprefix obj/, crt crt/$(ARCH) include))
+OBJ_DIRS = $(sort $(patsubst %/,%,$(dir $(ALL_LIBS) $(ALL_TOOLS) $(OBJS) $(LDSO_OBJS) $(GENH) $(GENH_INT))) $(addprefix obj/, crt crt/$(ARCH) include))
$(ALL_LIBS) $(ALL_TOOLS) $(CRT_LIBS:lib/%=obj/crt/%) $(OBJS) $(LOBJS) $(GENH) $(GENH_INT): | $(OBJ_DIRS)
obj/src/internal/version.o obj/src/internal/version.lo: obj/src/internal/version.h
-obj/crt/rcrt1.o obj/src/ldso/dlstart.lo obj/src/ldso/dynlink.lo: $(srcdir)/src/internal/dynlink.h $(srcdir)/arch/$(ARCH)/reloc.h
+obj/crt/rcrt1.o obj/ldso/dlstart.lo obj/ldso/dynlink.lo: $(srcdir)/src/internal/dynlink.h $(srcdir)/arch/$(ARCH)/reloc.h
-obj/crt/crt1.o obj/crt/scrt1.o obj/crt/rcrt1.o obj/src/ldso/dlstart.lo: $(srcdir)/arch/$(ARCH)/crt_arch.h
+obj/crt/crt1.o obj/crt/scrt1.o obj/crt/rcrt1.o obj/ldso/dlstart.lo: $(srcdir)/arch/$(ARCH)/crt_arch.h
-obj/crt/rcrt1.o: $(srcdir)/src/ldso/dlstart.c
+obj/crt/rcrt1.o: $(srcdir)/ldso/dlstart.c
obj/crt/Scrt1.o obj/crt/rcrt1.o: CFLAGS_ALL += -fPIC
src/env/__libc_start_main.c src/env/__init_tls.c \
src/thread/__set_thread_area.c src/env/__stack_chk_fail.c \
src/string/memset.c src/string/memcpy.c \
- src/ldso/dlstart.c src/ldso/dynlink.c
+ ldso/dlstart.c ldso/dynlink.c
$(NOSSP_SRCS:%.c=obj/%.o) $(NOSSP_SRCS:%.c=obj/%.lo): CFLAGS_ALL += $(CFLAGS_NOSSP)
$(CRT_LIBS:lib/%=obj/crt/%): CFLAGS_ALL += -DCRT
-$(LOBJS): CFLAGS_ALL += -fPIC -DSHARED
+$(LOBJS) $(LDSO_OBJS): CFLAGS_ALL += -fPIC
CC_CMD = $(CC) $(CFLAGS_ALL) -c -o $@ $<
obj/%.lo: $(srcdir)/%.c $(GENH) $(IMPH)
$(CC_CMD)
-lib/libc.so: $(LOBJS)
+lib/libc.so: $(LOBJS) $(LDSO_OBJS)
$(CC) $(CFLAGS_ALL) $(LDFLAGS_ALL) -nostdlib -shared \
-Wl,-e,_dlstart -Wl,-Bsymbolic-functions \
- -o $@ $(LOBJS) $(LIBCC)
+ -o $@ $(LOBJS) $(LDSO_OBJS) $(LIBCC)
lib/libc.a: $(OBJS)
rm -f $@
#define SHARED
#define START "_start"
#define _dlstart_c _start_c
-#include "../src/ldso/dlstart.c"
+#include "../ldso/dlstart.c"
int main();
void _init() __attribute__((weak));
--- /dev/null
+#include <stddef.h>
+#include "dynlink.h"
+
+#ifndef START
+#define START "_dlstart"
+#endif
+
+#include "crt_arch.h"
+
+#ifndef GETFUNCSYM
+#define GETFUNCSYM(fp, sym, got) do { \
+ __attribute__((__visibility__("hidden"))) void sym(); \
+ static void (*static_func_ptr)() = sym; \
+ __asm__ __volatile__ ( "" : "+m"(static_func_ptr) : : "memory"); \
+ *(fp) = static_func_ptr; } while(0)
+#endif
+
+__attribute__((__visibility__("hidden")))
+void _dlstart_c(size_t *sp, size_t *dynv)
+{
+ size_t i, aux[AUX_CNT], dyn[DYN_CNT];
+ size_t *rel, rel_size, base;
+
+ int argc = *sp;
+ char **argv = (void *)(sp+1);
+
+ for (i=argc+1; argv[i]; i++);
+ size_t *auxv = (void *)(argv+i+1);
+
+ for (i=0; i<AUX_CNT; i++) aux[i] = 0;
+ for (i=0; auxv[i]; i+=2) if (auxv[i]<AUX_CNT)
+ aux[auxv[i]] = auxv[i+1];
+
+#if DL_FDPIC
+ struct fdpic_loadseg *segs, fakeseg;
+ size_t j;
+ if (dynv) {
+ /* crt_arch.h entry point asm is responsible for reserving
+ * space and moving the extra fdpic arguments to the stack
+ * vector where they are easily accessible from C. */
+ segs = ((struct fdpic_loadmap *)(sp[-1] ? sp[-1] : sp[-2]))->segs;
+ } else {
+ /* If dynv is null, the entry point was started from loader
+ * that is not fdpic-aware. We can assume normal fixed-
+ * displacement ELF loading was performed, but when ldso was
+ * run as a command, finding the Ehdr is a heursitic: we
+ * have to assume Phdrs start in the first 4k of the file. */
+ base = aux[AT_BASE];
+ if (!base) base = aux[AT_PHDR] & -4096;
+ segs = &fakeseg;
+ segs[0].addr = base;
+ segs[0].p_vaddr = 0;
+ segs[0].p_memsz = -1;
+ Ehdr *eh = (void *)base;
+ Phdr *ph = (void *)(base + eh->e_phoff);
+ size_t phnum = eh->e_phnum;
+ size_t phent = eh->e_phentsize;
+ while (phnum-- && ph->p_type != PT_DYNAMIC)
+ ph = (void *)((size_t)ph + phent);
+ dynv = (void *)(base + ph->p_vaddr);
+ }
+#endif
+
+ for (i=0; i<DYN_CNT; i++) dyn[i] = 0;
+ for (i=0; dynv[i]; i+=2) if (dynv[i]<DYN_CNT)
+ dyn[dynv[i]] = dynv[i+1];
+
+#if DL_FDPIC
+ for (i=0; i<DYN_CNT; i++) {
+ if (i==DT_RELASZ || i==DT_RELSZ) continue;
+ if (!dyn[i]) continue;
+ for (j=0; dyn[i]-segs[j].p_vaddr >= segs[j].p_memsz; j++);
+ dyn[i] += segs[j].addr - segs[j].p_vaddr;
+ }
+ base = 0;
+
+ const Sym *syms = (void *)dyn[DT_SYMTAB];
+
+ rel = (void *)dyn[DT_RELA];
+ rel_size = dyn[DT_RELASZ];
+ for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
+ if (!IS_RELATIVE(rel[1], syms)) continue;
+ for (j=0; rel[0]-segs[j].p_vaddr >= segs[j].p_memsz; j++);
+ size_t *rel_addr = (void *)
+ (rel[0] + segs[j].addr - segs[j].p_vaddr);
+ if (R_TYPE(rel[1]) == REL_FUNCDESC_VAL) {
+ *rel_addr += segs[rel_addr[1]].addr
+ - segs[rel_addr[1]].p_vaddr
+ + syms[R_SYM(rel[1])].st_value;
+ rel_addr[1] = dyn[DT_PLTGOT];
+ } else {
+ size_t val = syms[R_SYM(rel[1])].st_value;
+ for (j=0; val-segs[j].p_vaddr >= segs[j].p_memsz; j++);
+ *rel_addr = rel[2] + segs[j].addr - segs[j].p_vaddr + val;
+ }
+ }
+#else
+ /* If the dynamic linker is invoked as a command, its load
+ * address is not available in the aux vector. Instead, compute
+ * the load address as the difference between &_DYNAMIC and the
+ * virtual address in the PT_DYNAMIC program header. */
+ base = aux[AT_BASE];
+ if (!base) {
+ size_t phnum = aux[AT_PHNUM];
+ size_t phentsize = aux[AT_PHENT];
+ Phdr *ph = (void *)aux[AT_PHDR];
+ for (i=phnum; i--; ph = (void *)((char *)ph + phentsize)) {
+ if (ph->p_type == PT_DYNAMIC) {
+ base = (size_t)dynv - ph->p_vaddr;
+ break;
+ }
+ }
+ }
+
+ /* MIPS uses an ugly packed form for GOT relocations. Since we
+ * can't make function calls yet and the code is tiny anyway,
+ * it's simply inlined here. */
+ if (NEED_MIPS_GOT_RELOCS) {
+ size_t local_cnt = 0;
+ size_t *got = (void *)(base + dyn[DT_PLTGOT]);
+ for (i=0; dynv[i]; i+=2) if (dynv[i]==DT_MIPS_LOCAL_GOTNO)
+ local_cnt = dynv[i+1];
+ for (i=0; i<local_cnt; i++) got[i] += base;
+ }
+
+ rel = (void *)(base+dyn[DT_REL]);
+ rel_size = dyn[DT_RELSZ];
+ for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t)) {
+ if (!IS_RELATIVE(rel[1], 0)) continue;
+ size_t *rel_addr = (void *)(base + rel[0]);
+ *rel_addr += base;
+ }
+
+ rel = (void *)(base+dyn[DT_RELA]);
+ rel_size = dyn[DT_RELASZ];
+ for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
+ if (!IS_RELATIVE(rel[1], 0)) continue;
+ size_t *rel_addr = (void *)(base + rel[0]);
+ *rel_addr = base + rel[2];
+ }
+#endif
+
+ stage2_func dls2;
+ GETFUNCSYM(&dls2, __dls2, base+dyn[DT_PLTGOT]);
+ dls2((void *)base, sp);
+}
--- /dev/null
+#define _GNU_SOURCE
+#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 "pthread_impl.h"
+#include "libc.h"
+#include "dynlink.h"
+
+static void error(const char *, ...);
+
+#define MAXP2(a,b) (-(-(a)&-(b)))
+#define ALIGN(x,y) ((x)+(y)-1 & -(y))
+
+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;
+
+ Phdr *phdr;
+ int phnum;
+ size_t phentsize;
+ int refcnt;
+ Sym *syms;
+ uint32_t *hashtab;
+ uint32_t *ghashtab;
+ int16_t *versym;
+ char *strings;
+ unsigned char *map;
+ size_t map_len;
+ dev_t dev;
+ ino_t ino;
+ signed char global;
+ char relocated;
+ char constructed;
+ char kernel_mapped;
+ struct dso **deps, *needed_by;
+ char *rpath_orig, *rpath;
+ struct tls_module tls;
+ size_t tls_id;
+ size_t relro_start, relro_end;
+ void **new_dtv;
+ unsigned char *new_tls;
+ volatile int new_dtv_idx, new_tls_idx;
+ 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;
+};
+
+int __init_tp(void *);
+void __init_libc(char **, char *);
+void *__copy_tls(unsigned char *);
+
+__attribute__((__visibility__("hidden")))
+const char *__libc_get_version(void);
+
+static struct builtin_tls {
+ char c;
+ 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;
+
+static struct dso ldso;
+static struct dso *head, *tail, *fini_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 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 = { ._m_type = PTHREAD_MUTEX_RECURSIVE };
+static struct fdpic_loadmap *app_loadmap;
+static struct fdpic_dummy_loadmap app_dummy_loadmap;
+
+struct debug *_dl_debug_addr = &debug;
+
+__attribute__((__visibility__("hidden")))
+void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;
+
+__attribute__((__visibility__("hidden")))
+extern 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);
+
+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);
+}
+#define fpaddr(p, v) ((void (*)())&(struct funcdesc){ \
+ laddr(p, v), (p)->got })
+#else
+#define laddr(p, v) (void *)((p)->base + (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;
+ uint32_t *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)
+ && (!strcmp(s, strings+syms[i].st_name)))
+ 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)
+ && !strcmp(s, dso->strings + dso->syms[i].st_name))
+ 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
+
+static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
+{
+ uint32_t h = 0, gh, gho, *ght;
+ size_t ghm = 0;
+ struct symdef def = {0};
+ for (; dso; dso=dso->next) {
+ Sym *sym;
+ if (!dso->global) continue;
+ if ((ght = dso->ghashtab)) {
+ if (!ghm) {
+ gh = gnu_hash(s);
+ int maskbits = 8 * sizeof ghm;
+ gho = gh / maskbits;
+ ghm = 1ul << gh % maskbits;
+ }
+ 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
+ || ARCH_SYM_REJECT_UND(sym))
+ 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;
+
+ if (def.sym && sym->st_info>>4 == STB_WEAK) continue;
+ def.sym = sym;
+ def.dso = dso;
+ if (sym->st_info>>4 == STB_GLOBAL) break;
+ }
+ return def;
+}
+
+__attribute__((__visibility__("hidden")))
+ptrdiff_t __tlsdesc_static(), __tlsdesc_dynamic();
+
+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;
+ sym_index = R_SYM(rel[1]);
+ reloc_addr = laddr(dso, rel[0]);
+ if (sym_index) {
+ sym = syms + sym_index;
+ name = strings + sym->st_name;
+ ctx = type==REL_COPY ? head->next : head;
+ def = (sym->st_info&0xf) == STT_SECTION
+ ? (struct symdef){ .dso = dso, .sym = sym }
+ : find_sym(ctx, name, type==REL_PLT);
+ if (!def.sym && (sym->st_shndx != SHN_UNDEF
+ || sym->st_info>>4 != STB_WEAK)) {
+ 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;
+ }
+
+ 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_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
+ tls_val = def.sym ? def.sym->st_value : 0;
+
+ 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_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 (runtime && 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;
+ 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
+ }
+ break;
+ default:
+ error("Error relocating %s: unsupported relocation type %d",
+ dso->name, type);
+ if (runtime) longjmp(*rtld_fail, 1);
+ continue;
+ }
+ }
+}
+
+/* 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 by setting up minimal malloc
+ * structures and then freeing them. */
+
+static void reclaim(struct dso *dso, size_t start, size_t end)
+{
+ size_t *a, *z;
+ 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;
+ start = start + 6*sizeof(size_t)-1 & -4*sizeof(size_t);
+ end = (end & -4*sizeof(size_t)) - 2*sizeof(size_t);
+ if (start>end || end-start < 4*sizeof(size_t)) return;
+ a = laddr(dso, start);
+ z = laddr(dso, end);
+ a[-2] = 1;
+ a[-1] = z[0] = end-start + 2*sizeof(size_t) | 1;
+ z[1] = 1;
+ free(a);
+}
+
+static void reclaim_gaps(struct dso *dso)
+{
+ Phdr *ph = dso->phdr;
+ size_t phcnt = dso->phnum;
+
+ if (DL_FDPIC) return; // FIXME
+ 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;
+ }
+ 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
+ && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
+ dso->phdr = (void *)(base + ph->p_vaddr
+ + (eh->e_phoff-ph->p_offset));
+ dso->phnum = eh->e_phnum;
+ dso->phentsize = eh->e_phentsize;
+ }
+ /* Reuse the existing mapping for the lowest-address LOAD */
+ if ((ph->p_vaddr & -PAGE_SIZE) == addr_min && !DL_NOMMU_SUPPORT)
+ continue;
+ 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));
+ 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) {
+ 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)
+ && errno != ENOSYS)
+ goto error;
+ break;
+ }
+done_mapping:
+ dso->base = base;
+ dso->dynv = laddr(dso, dyn);
+ if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);
+ if (!runtime) reclaim_gaps(dso);
+ 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, $ORIGIN can be processed safely
+ * since the library's pathname came from a trusted source
+ * (either system paths or a call to dlopen). */
+ if (libc.secure)
+ return 0;
+ l = readlink("/proc/self/exe", buf, buf_size);
+ if (l == -1) switch (errno) {
+ case ENOENT:
+ case ENOTDIR:
+ case EACCES:
+ break;
+ default:
+ return -1;
+ }
+ if (l >= buf_size)
+ return 0;
+ buf[l] = 0;
+ origin = buf;
+ } else {
+ origin = p->name;
+ }
+ t = strrchr(origin, '/');
+ l = t ? t-origin : 0;
+ p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
+ if (!p->rpath) return -1;
+
+ d = p->rpath;
+ s = p->rpath_orig;
+ while ((t=strchr(s, '$'))) {
+ 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 p == MAP_FAILED ? 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;
+ }
+ }
+}
+
+static struct dso *load_library(const char *name, struct dso *needed_by)
+{
+ char buf[2*NAME_MAX+2];
+ 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;
+ return 0;
+ }
+
+ /* Catch and block attempts to reload the implementation itself */
+ if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
+ static const char *rp, reserved[] =
+ "c\0pthread\0rt\0m\0dl\0util\0xnet\0";
+ char *z = strchr(name, '.');
+ if (z) {
+ size_t l = z-name;
+ for (rp=reserved; *rp && strncmp(name+3, rp, l-3); rp+=strlen(rp)+1);
+ 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.next ? ldso.next : &ldso;
+ }
+ return &ldso;
+ }
+ if (strchr(name, '/')) {
+ pathname = name;
+ fd = open(name, O_RDONLY|O_CLOEXEC);
+ } else {
+ /* Search for the name to see if it's already loaded */
+ for (p=head->next; p; p=p->next) {
+ if (p->shortname && !strcmp(p->shortname, name)) {
+ p->refcnt++;
+ return p;
+ }
+ }
+ if (strlen(name) > NAME_MAX) return 0;
+ fd = -1;
+ if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
+ for (p=needed_by; fd == -1 && p; p=p->needed_by) {
+ if (fixup_rpath(p, buf, sizeof buf) < 0)
+ fd = -2; /* Inhibit further search. */
+ if (p->rpath)
+ fd = path_open(name, p->rpath, buf, sizeof buf);
+ }
+ if (fd == -1) {
+ if (!sys_path) {
+ char *prefix = 0;
+ size_t prefix_len;
+ if (ldso.name[0]=='/') {
+ char *s, *t, *z;
+ for (s=t=z=ldso.name; *s; s++)
+ if (*s=='/') z=t, t=s;
+ prefix_len = z-ldso.name;
+ if (prefix_len < PATH_MAX)
+ prefix = ldso.name;
+ }
+ if (!prefix) {
+ prefix = "";
+ prefix_len = 0;
+ }
+ char etc_ldso_path[prefix_len + 1
+ + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
+ snprintf(etc_ldso_path, sizeof etc_ldso_path,
+ "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
+ (int)prefix_len, prefix);
+ FILE *f = fopen(etc_ldso_path, "rbe");
+ if (f) {
+ if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
+ free(sys_path);
+ sys_path = "";
+ }
+ fclose(f);
+ } else if (errno != ENOENT) {
+ sys_path = "";
+ }
+ }
+ if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
+ fd = path_open(name, sys_path, buf, sizeof buf);
+ }
+ pathname = buf;
+ }
+ if (fd < 0) return 0;
+ if (fstat(fd, &st) < 0) {
+ close(fd);
+ return 0;
+ }
+ for (p=head->next; p; p=p->next) {
+ if (p->dev == st.st_dev && p->ino == st.st_ino) {
+ /* 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);
+ p->refcnt++;
+ return p;
+ }
+ }
+ map = noload ? 0 : map_library(fd, &temp_dso);
+ close(fd);
+ if (!map) return 0;
+
+ /* 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);
+ decode_dyn(p);
+ p->dev = st.st_dev;
+ p->ino = st.st_ino;
+ p->refcnt = 1;
+ p->needed_by = needed_by;
+ p->name = p->buf;
+ 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 + ( (tls_align-1) &
+ -(tls_offset + (uintptr_t)p->tls.image) );
+ 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;
+
+ if (DL_FDPIC) makefuncdescs(p);
+
+ if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
+
+ return p;
+}
+
+static void load_deps(struct dso *p)
+{
+ size_t i, ndeps=0;
+ struct dso ***deps = &p->deps, **tmp, *dep;
+ for (; p; p=p->next) {
+ for (i=0; p->dynv[i]; i+=2) {
+ if (p->dynv[i] != DT_NEEDED) continue;
+ dep = load_library(p->strings + p->dynv[i+1], p);
+ 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;
+ }
+ if (runtime) {
+ tmp = realloc(*deps, sizeof(*tmp)*(ndeps+2));
+ if (!tmp) longjmp(*rtld_fail, 1);
+ tmp[ndeps++] = dep;
+ tmp[ndeps] = 0;
+ *deps = tmp;
+ }
+ }
+ }
+}
+
+static void load_preload(char *s)
+{
+ 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;
+ load_library(s, 0);
+ *z = tmp;
+ }
+}
+
+static void make_global(struct dso *p)
+{
+ for (; p; p=p->next) p->global = 1;
+}
+
+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] = sym-p->syms << 8 | 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 &&
+ mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_start, PROT_READ)
+ && errno != ENOSYS) {
+ 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;
+ }
+ 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];
+ for (p=fini_head; p; p=p->fini_next) {
+ 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 void do_init_fini(struct dso *p)
+{
+ size_t dyn[DYN_CNT];
+ int need_locking = libc.threads_minus_1;
+ /* Allow recursive calls that arise when a library calls
+ * dlopen from one of its constructors, but block any
+ * other threads until all ctors have finished. */
+ if (need_locking) pthread_mutex_lock(&init_fini_lock);
+ for (; p; p=p->prev) {
+ if (p->constructed) continue;
+ p->constructed = 1;
+ 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;
+ }
+#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++)();
+ }
+ if (!need_locking && libc.threads_minus_1) {
+ need_locking = 1;
+ pthread_mutex_lock(&init_fini_lock);
+ }
+ }
+ if (need_locking) pthread_mutex_unlock(&init_fini_lock);
+}
+
+void __libc_start_init(void)
+{
+ do_init_fini(tail);
+}
+
+static void dl_debug_state(void)
+{
+}
+
+weak_alias(dl_debug_state, _dl_debug_state);
+
+void __init_tls(size_t *auxv)
+{
+}
+
+__attribute__((__visibility__("hidden")))
+void *__tls_get_new(size_t *v)
+{
+ pthread_t self = __pthread_self();
+
+ /* Block signals to make accessing new TLS async-signal-safe */
+ sigset_t set;
+ __block_all_sigs(&set);
+ if (v[0]<=(size_t)self->dtv[0]) {
+ __restore_sigs(&set);
+ return (char *)self->dtv[v[0]]+v[1]+DTP_OFFSET;
+ }
+
+ /* This is safe without any locks held because, if the caller
+ * is able to request the Nth entry of the DTV, the DSO list
+ * must be valid at least that far out and it was synchronized
+ * at program startup or by an already-completed call to dlopen. */
+ struct dso *p;
+ for (p=head; p->tls_id != v[0]; p=p->next);
+
+ /* Get new DTV space from new DSO if needed */
+ if (v[0] > (size_t)self->dtv[0]) {
+ void **newdtv = p->new_dtv +
+ (v[0]+1)*a_fetch_add(&p->new_dtv_idx,1);
+ memcpy(newdtv, self->dtv,
+ ((size_t)self->dtv[0]+1) * sizeof(void *));
+ newdtv[0] = (void *)v[0];
+ self->dtv = self->dtv_copy = newdtv;
+ }
+
+ /* Get new TLS memory from all new DSOs up to the requested one */
+ unsigned char *mem;
+ for (p=head; ; p=p->next) {
+ if (!p->tls_id || self->dtv[p->tls_id]) continue;
+ mem = p->new_tls + (p->tls.size + p->tls.align)
+ * a_fetch_add(&p->new_tls_idx,1);
+ mem += ((uintptr_t)p->tls.image - (uintptr_t)mem)
+ & (p->tls.align-1);
+ self->dtv[p->tls_id] = mem;
+ memcpy(mem, p->tls.image, p->tls.len);
+ if (p->tls_id == v[0]) break;
+ }
+ __restore_sigs(&set);
+ return mem + v[1] + DTP_OFFSET;
+}
+
+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);
+}
+
+/* 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. */
+
+__attribute__((__visibility__("hidden")))
+void __dls2(unsigned char *base, size_t *sp)
+{
+ if (DL_FDPIC) {
+ void *p1 = (void *)sp[-2];
+ void *p2 = (void *)sp[-1];
+ if (!p1) {
+ size_t *auxv, aux[AUX_CNT];
+ for (auxv=sp+1+*sp+1; *auxv; auxv++); auxv++;
+ 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.global = 1;
+ 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-3, __dls3, looking it up
+ * symbolically as a barrier against moving the address
+ * load across the above relocation processing. */
+ struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
+ if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp);
+ else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp);
+}
+
+/* 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. */
+
+_Noreturn void __dls3(size_t *sp)
+{
+ static struct dso app, vdso;
+ size_t aux[AUX_CNT], *auxv;
+ size_t i;
+ char *env_preload=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;
+ for (i=argc+1; argv[i]; i++);
+ libc.auxv = auxv = (void *)(argv+i+1);
+ decode_vec(auxv, aux, AUX_CNT);
+ __hwcap = aux[AT_HWCAP];
+ 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]);
+
+ /* 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. */
+ libc.tls_size = sizeof builtin_tls;
+ libc.tls_align = tls_align;
+ if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
+ a_crash();
+ }
+
+ /* 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))
+ && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
+ 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 {
+ 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_get_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);
+ }
+ runtime = 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);
+ }
+ runtime = 0;
+ 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 = &app.tls;
+ app.tls_id = tls_cnt = 1;
+#ifdef TLS_ABOVE_TP
+ app.tls.offset = 0;
+ tls_offset = app.tls.size
+ + ( -((uintptr_t)app.tls.image + app.tls.size)
+ & (app.tls.align-1) );
+#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);
+ }
+ app.global = 1;
+ 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;
+ }
+
+ /* Attach to vdso, if provided by the kernel */
+ if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {
+ 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.global = 1;
+ vdso.relocated = 1;
+ decode_dyn(&vdso);
+ vdso.prev = &ldso;
+ ldso.next = &vdso;
+ }
+
+ /* Initial dso chain consists only of the app. */
+ head = tail = &app;
+
+ /* Donate unused parts of app and library mapping to malloc */
+ reclaim_gaps(&app);
+ reclaim_gaps(&ldso);
+
+ /* Load preload/needed libraries, add their symbols to the global
+ * namespace, and perform all remaining relocations. */
+ if (env_preload) load_preload(env_preload);
+ load_deps(&app);
+ make_global(&app);
+
+#ifndef DYNAMIC_IS_RO
+ for (i=0; app.dynv[i]; i+=2)
+ if (app.dynv[i]==DT_DEBUG)
+ app.dynv[i+1] = (size_t)&debug;
+#endif
+
+ /* The main program must be relocated LAST since it may contin
+ * copy relocations which depend on libraries' relocations. */
+ reloc_all(app.next);
+ reloc_all(&app);
+
+ update_tls_size();
+ if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
+ void *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);
+ }
+ 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;
+ }
+ static_tls_cnt = tls_cnt;
+
+ if (ldso_fail) _exit(127);
+ if (ldd_mode) _exit(0);
+
+ /* 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();
+
+ errno = 0;
+
+ CRTJMP((void *)aux[AT_ENTRY], argv-1);
+ for(;;);
+}
+
+void *dlopen(const char *file, int mode)
+{
+ struct dso *volatile p, *orig_tail, *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;
+
+ if (!file) return head;
+
+ pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+ pthread_rwlock_wrlock(&lock);
+ __inhibit_ptc();
+
+ p = 0;
+ orig_tls_tail = tls_tail;
+ orig_tls_cnt = tls_cnt;
+ orig_tls_offset = tls_offset;
+ orig_tls_align = tls_align;
+ orig_tail = tail;
+ noload = mode & RTLD_NOLOAD;
+
+ rtld_fail = &jb;
+ if (setjmp(*rtld_fail)) {
+ /* Clean up anything new that was (partially) loaded */
+ if (p && p->deps) for (i=0; p->deps[i]; i++)
+ if (p->deps[i]->global < 0)
+ p->deps[i]->global = 0;
+ 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);
+ unmap_library(p);
+ free(p);
+ }
+ if (!orig_tls_tail) libc.tls_head = 0;
+ tls_tail = orig_tls_tail;
+ tls_cnt = orig_tls_cnt;
+ tls_offset = orig_tls_offset;
+ tls_align = orig_tls_align;
+ tail = orig_tail;
+ tail->next = 0;
+ p = 0;
+ goto end;
+ } else p = load_library(file, head);
+
+ if (!p) {
+ error(noload ?
+ "Library %s is not already loaded" :
+ "Error loading shared library %s: %m",
+ file);
+ goto end;
+ }
+
+ /* First load handling */
+ if (!p->deps) {
+ load_deps(p);
+ if (p->deps) for (i=0; p->deps[i]; i++)
+ if (!p->deps[i]->global)
+ p->deps[i]->global = -1;
+ if (!p->global) p->global = -1;
+ reloc_all(p);
+ if (p->deps) for (i=0; p->deps[i]; i++)
+ if (p->deps[i]->global < 0)
+ p->deps[i]->global = 0;
+ if (p->global < 0) p->global = 0;
+ }
+
+ if (mode & RTLD_GLOBAL) {
+ if (p->deps) for (i=0; p->deps[i]; i++)
+ p->deps[i]->global = 1;
+ p->global = 1;
+ }
+
+ update_tls_size();
+ _dl_debug_state();
+ orig_tail = tail;
+end:
+ __release_ptc();
+ if (p) gencnt++;
+ pthread_rwlock_unlock(&lock);
+ if (p) do_init_fini(orig_tail);
+ pthread_setcancelstate(cs, 0);
+ return p;
+}
+
+__attribute__((__visibility__("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
+ < p->loadmap->segs[i].p_memsz)
+ return p;
+ }
+ } else {
+ if (a-(size_t)p->map < p->map_len)
+ return p;
+ }
+ }
+ return 0;
+}
+
+void *__tls_get_addr(size_t *);
+
+static void *do_dlsym(struct dso *p, const char *s, void *ra)
+{
+ size_t i;
+ uint32_t h = 0, gh = 0, *ght;
+ Sym *sym;
+ if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) {
+ if (p == RTLD_DEFAULT) {
+ p = head;
+ } else if (p == RTLD_NEXT) {
+ p = addr2dso((size_t)ra);
+ if (!p) p=head;
+ p = p->next;
+ }
+ struct symdef def = find_sym(p, s, 0);
+ if (!def.sym) goto failed;
+ if ((def.sym->st_info&0xf) == STT_TLS)
+ return __tls_get_addr((size_t []){def.dso->tls_id, def.sym->st_value});
+ 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);
+ }
+ if (__dl_invalid_handle(p))
+ return 0;
+ if ((ght = p->ghashtab)) {
+ gh = gnu_hash(s);
+ sym = gnu_lookup(gh, ght, p, s);
+ } else {
+ h = sysv_hash(s);
+ sym = sysv_lookup(s, h, p);
+ }
+ if (sym && (sym->st_info&0xf) == STT_TLS)
+ return __tls_get_addr((size_t []){p->tls_id, sym->st_value});
+ if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)
+ return p->funcdescs + (sym - p->syms);
+ if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
+ return laddr(p, sym->st_value);
+ if (p->deps) for (i=0; p->deps[i]; i++) {
+ if ((ght = p->deps[i]->ghashtab)) {
+ if (!gh) gh = gnu_hash(s);
+ sym = gnu_lookup(gh, ght, p->deps[i], s);
+ } else {
+ if (!h) h = sysv_hash(s);
+ sym = sysv_lookup(s, h, p->deps[i]);
+ }
+ if (sym && (sym->st_info&0xf) == STT_TLS)
+ return __tls_get_addr((size_t []){p->deps[i]->tls_id, sym->st_value});
+ if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)
+ return p->deps[i]->funcdescs + (sym - p->deps[i]->syms);
+ if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
+ return laddr(p->deps[i], sym->st_value);
+ }
+failed:
+ error("Symbol not found: %s", s);
+ return 0;
+}
+
+int dladdr(const void *addr, Dl_info *info)
+{
+ struct dso *p;
+ Sym *sym, *bestsym;
+ uint32_t nsym;
+ char *strings;
+ void *best = 0;
+
+ pthread_rwlock_rdlock(&lock);
+ p = addr2dso((size_t)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 = ((size_t)addr-(size_t)p->funcdescs)
+ / sizeof(*p->funcdescs);
+ if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
+ best = p->funcdescs + idx;
+ bestsym = sym + idx;
+ }
+ }
+
+ if (!best) for (; nsym; nsym--, sym++) {
+ if (sym->st_value
+ && (1<<(sym->st_info&0xf) & OK_TYPES)
+ && (1<<(sym->st_info>>4) & OK_BINDS)) {
+ void *symaddr = laddr(p, sym->st_value);
+ if (symaddr > addr || symaddr < best)
+ continue;
+ best = symaddr;
+ bestsym = sym;
+ if (addr == symaddr)
+ break;
+ }
+ }
+
+ if (!best) return 0;
+
+ if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
+ best = p->funcdescs + (bestsym - p->syms);
+
+ info->dli_fname = p->name;
+ info->dli_fbase = p->base;
+ info->dli_sname = strings + bestsym->st_name;
+ info->dli_saddr = best;
+
+ return 1;
+}
+
+__attribute__((__visibility__("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;
+}
+
+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;
+}
+
+__attribute__((__visibility__("hidden")))
+void __dl_vseterr(const char *, va_list);
+
+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);
+}
+++ /dev/null
-#include <stddef.h>
-#include "dynlink.h"
-
-#ifdef SHARED
-
-#ifndef START
-#define START "_dlstart"
-#endif
-
-#include "crt_arch.h"
-
-#ifndef GETFUNCSYM
-#define GETFUNCSYM(fp, sym, got) do { \
- __attribute__((__visibility__("hidden"))) void sym(); \
- static void (*static_func_ptr)() = sym; \
- __asm__ __volatile__ ( "" : "+m"(static_func_ptr) : : "memory"); \
- *(fp) = static_func_ptr; } while(0)
-#endif
-
-__attribute__((__visibility__("hidden")))
-void _dlstart_c(size_t *sp, size_t *dynv)
-{
- size_t i, aux[AUX_CNT], dyn[DYN_CNT];
- size_t *rel, rel_size, base;
-
- int argc = *sp;
- char **argv = (void *)(sp+1);
-
- for (i=argc+1; argv[i]; i++);
- size_t *auxv = (void *)(argv+i+1);
-
- for (i=0; i<AUX_CNT; i++) aux[i] = 0;
- for (i=0; auxv[i]; i+=2) if (auxv[i]<AUX_CNT)
- aux[auxv[i]] = auxv[i+1];
-
-#if DL_FDPIC
- struct fdpic_loadseg *segs, fakeseg;
- size_t j;
- if (dynv) {
- /* crt_arch.h entry point asm is responsible for reserving
- * space and moving the extra fdpic arguments to the stack
- * vector where they are easily accessible from C. */
- segs = ((struct fdpic_loadmap *)(sp[-1] ? sp[-1] : sp[-2]))->segs;
- } else {
- /* If dynv is null, the entry point was started from loader
- * that is not fdpic-aware. We can assume normal fixed-
- * displacement ELF loading was performed, but when ldso was
- * run as a command, finding the Ehdr is a heursitic: we
- * have to assume Phdrs start in the first 4k of the file. */
- base = aux[AT_BASE];
- if (!base) base = aux[AT_PHDR] & -4096;
- segs = &fakeseg;
- segs[0].addr = base;
- segs[0].p_vaddr = 0;
- segs[0].p_memsz = -1;
- Ehdr *eh = (void *)base;
- Phdr *ph = (void *)(base + eh->e_phoff);
- size_t phnum = eh->e_phnum;
- size_t phent = eh->e_phentsize;
- while (phnum-- && ph->p_type != PT_DYNAMIC)
- ph = (void *)((size_t)ph + phent);
- dynv = (void *)(base + ph->p_vaddr);
- }
-#endif
-
- for (i=0; i<DYN_CNT; i++) dyn[i] = 0;
- for (i=0; dynv[i]; i+=2) if (dynv[i]<DYN_CNT)
- dyn[dynv[i]] = dynv[i+1];
-
-#if DL_FDPIC
- for (i=0; i<DYN_CNT; i++) {
- if (i==DT_RELASZ || i==DT_RELSZ) continue;
- if (!dyn[i]) continue;
- for (j=0; dyn[i]-segs[j].p_vaddr >= segs[j].p_memsz; j++);
- dyn[i] += segs[j].addr - segs[j].p_vaddr;
- }
- base = 0;
-
- const Sym *syms = (void *)dyn[DT_SYMTAB];
-
- rel = (void *)dyn[DT_RELA];
- rel_size = dyn[DT_RELASZ];
- for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
- if (!IS_RELATIVE(rel[1], syms)) continue;
- for (j=0; rel[0]-segs[j].p_vaddr >= segs[j].p_memsz; j++);
- size_t *rel_addr = (void *)
- (rel[0] + segs[j].addr - segs[j].p_vaddr);
- if (R_TYPE(rel[1]) == REL_FUNCDESC_VAL) {
- *rel_addr += segs[rel_addr[1]].addr
- - segs[rel_addr[1]].p_vaddr
- + syms[R_SYM(rel[1])].st_value;
- rel_addr[1] = dyn[DT_PLTGOT];
- } else {
- size_t val = syms[R_SYM(rel[1])].st_value;
- for (j=0; val-segs[j].p_vaddr >= segs[j].p_memsz; j++);
- *rel_addr = rel[2] + segs[j].addr - segs[j].p_vaddr + val;
- }
- }
-#else
- /* If the dynamic linker is invoked as a command, its load
- * address is not available in the aux vector. Instead, compute
- * the load address as the difference between &_DYNAMIC and the
- * virtual address in the PT_DYNAMIC program header. */
- base = aux[AT_BASE];
- if (!base) {
- size_t phnum = aux[AT_PHNUM];
- size_t phentsize = aux[AT_PHENT];
- Phdr *ph = (void *)aux[AT_PHDR];
- for (i=phnum; i--; ph = (void *)((char *)ph + phentsize)) {
- if (ph->p_type == PT_DYNAMIC) {
- base = (size_t)dynv - ph->p_vaddr;
- break;
- }
- }
- }
-
- /* MIPS uses an ugly packed form for GOT relocations. Since we
- * can't make function calls yet and the code is tiny anyway,
- * it's simply inlined here. */
- if (NEED_MIPS_GOT_RELOCS) {
- size_t local_cnt = 0;
- size_t *got = (void *)(base + dyn[DT_PLTGOT]);
- for (i=0; dynv[i]; i+=2) if (dynv[i]==DT_MIPS_LOCAL_GOTNO)
- local_cnt = dynv[i+1];
- for (i=0; i<local_cnt; i++) got[i] += base;
- }
-
- rel = (void *)(base+dyn[DT_REL]);
- rel_size = dyn[DT_RELSZ];
- for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t)) {
- if (!IS_RELATIVE(rel[1], 0)) continue;
- size_t *rel_addr = (void *)(base + rel[0]);
- *rel_addr += base;
- }
-
- rel = (void *)(base+dyn[DT_RELA]);
- rel_size = dyn[DT_RELASZ];
- for (; rel_size; rel+=3, rel_size-=3*sizeof(size_t)) {
- if (!IS_RELATIVE(rel[1], 0)) continue;
- size_t *rel_addr = (void *)(base + rel[0]);
- *rel_addr = base + rel[2];
- }
-#endif
-
- stage2_func dls2;
- GETFUNCSYM(&dls2, __dls2, base+dyn[DT_PLTGOT]);
- dls2((void *)base, sp);
-}
-
-#endif
+++ /dev/null
-#ifdef SHARED
-#define _GNU_SOURCE
-#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 "pthread_impl.h"
-#include "libc.h"
-#include "dynlink.h"
-
-static void error(const char *, ...);
-
-#define MAXP2(a,b) (-(-(a)&-(b)))
-#define ALIGN(x,y) ((x)+(y)-1 & -(y))
-
-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;
-
- Phdr *phdr;
- int phnum;
- size_t phentsize;
- int refcnt;
- Sym *syms;
- uint32_t *hashtab;
- uint32_t *ghashtab;
- int16_t *versym;
- char *strings;
- unsigned char *map;
- size_t map_len;
- dev_t dev;
- ino_t ino;
- signed char global;
- char relocated;
- char constructed;
- char kernel_mapped;
- struct dso **deps, *needed_by;
- char *rpath_orig, *rpath;
- struct tls_module tls;
- size_t tls_id;
- size_t relro_start, relro_end;
- void **new_dtv;
- unsigned char *new_tls;
- volatile int new_dtv_idx, new_tls_idx;
- 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;
-};
-
-int __init_tp(void *);
-void __init_libc(char **, char *);
-void *__copy_tls(unsigned char *);
-
-__attribute__((__visibility__("hidden")))
-const char *__libc_get_version(void);
-
-static struct builtin_tls {
- char c;
- 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;
-
-static struct dso ldso;
-static struct dso *head, *tail, *fini_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 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 = { ._m_type = PTHREAD_MUTEX_RECURSIVE };
-static struct fdpic_loadmap *app_loadmap;
-static struct fdpic_dummy_loadmap app_dummy_loadmap;
-
-struct debug *_dl_debug_addr = &debug;
-
-__attribute__((__visibility__("hidden")))
-void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;
-
-__attribute__((__visibility__("hidden")))
-extern 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);
-
-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);
-}
-#define fpaddr(p, v) ((void (*)())&(struct funcdesc){ \
- laddr(p, v), (p)->got })
-#else
-#define laddr(p, v) (void *)((p)->base + (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;
- uint32_t *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)
- && (!strcmp(s, strings+syms[i].st_name)))
- 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)
- && !strcmp(s, dso->strings + dso->syms[i].st_name))
- 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
-
-static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
-{
- uint32_t h = 0, gh, gho, *ght;
- size_t ghm = 0;
- struct symdef def = {0};
- for (; dso; dso=dso->next) {
- Sym *sym;
- if (!dso->global) continue;
- if ((ght = dso->ghashtab)) {
- if (!ghm) {
- gh = gnu_hash(s);
- int maskbits = 8 * sizeof ghm;
- gho = gh / maskbits;
- ghm = 1ul << gh % maskbits;
- }
- 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
- || ARCH_SYM_REJECT_UND(sym))
- 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;
-
- if (def.sym && sym->st_info>>4 == STB_WEAK) continue;
- def.sym = sym;
- def.dso = dso;
- if (sym->st_info>>4 == STB_GLOBAL) break;
- }
- return def;
-}
-
-__attribute__((__visibility__("hidden")))
-ptrdiff_t __tlsdesc_static(), __tlsdesc_dynamic();
-
-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;
- sym_index = R_SYM(rel[1]);
- reloc_addr = laddr(dso, rel[0]);
- if (sym_index) {
- sym = syms + sym_index;
- name = strings + sym->st_name;
- ctx = type==REL_COPY ? head->next : head;
- def = (sym->st_info&0xf) == STT_SECTION
- ? (struct symdef){ .dso = dso, .sym = sym }
- : find_sym(ctx, name, type==REL_PLT);
- if (!def.sym && (sym->st_shndx != SHN_UNDEF
- || sym->st_info>>4 != STB_WEAK)) {
- 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;
- }
-
- 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_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
- tls_val = def.sym ? def.sym->st_value : 0;
-
- 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_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 (runtime && 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;
- 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
- }
- break;
- default:
- error("Error relocating %s: unsupported relocation type %d",
- dso->name, type);
- if (runtime) longjmp(*rtld_fail, 1);
- continue;
- }
- }
-}
-
-/* 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 by setting up minimal malloc
- * structures and then freeing them. */
-
-static void reclaim(struct dso *dso, size_t start, size_t end)
-{
- size_t *a, *z;
- 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;
- start = start + 6*sizeof(size_t)-1 & -4*sizeof(size_t);
- end = (end & -4*sizeof(size_t)) - 2*sizeof(size_t);
- if (start>end || end-start < 4*sizeof(size_t)) return;
- a = laddr(dso, start);
- z = laddr(dso, end);
- a[-2] = 1;
- a[-1] = z[0] = end-start + 2*sizeof(size_t) | 1;
- z[1] = 1;
- free(a);
-}
-
-static void reclaim_gaps(struct dso *dso)
-{
- Phdr *ph = dso->phdr;
- size_t phcnt = dso->phnum;
-
- if (DL_FDPIC) return; // FIXME
- 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;
- }
- 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
- && eh->e_phoff+phsize <= ph->p_offset+ph->p_filesz) {
- dso->phdr = (void *)(base + ph->p_vaddr
- + (eh->e_phoff-ph->p_offset));
- dso->phnum = eh->e_phnum;
- dso->phentsize = eh->e_phentsize;
- }
- /* Reuse the existing mapping for the lowest-address LOAD */
- if ((ph->p_vaddr & -PAGE_SIZE) == addr_min && !DL_NOMMU_SUPPORT)
- continue;
- 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));
- 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) {
- 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)
- && errno != ENOSYS)
- goto error;
- break;
- }
-done_mapping:
- dso->base = base;
- dso->dynv = laddr(dso, dyn);
- if (dso->tls.size) dso->tls.image = laddr(dso, tls_image);
- if (!runtime) reclaim_gaps(dso);
- 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, $ORIGIN can be processed safely
- * since the library's pathname came from a trusted source
- * (either system paths or a call to dlopen). */
- if (libc.secure)
- return 0;
- l = readlink("/proc/self/exe", buf, buf_size);
- if (l == -1) switch (errno) {
- case ENOENT:
- case ENOTDIR:
- case EACCES:
- break;
- default:
- return -1;
- }
- if (l >= buf_size)
- return 0;
- buf[l] = 0;
- origin = buf;
- } else {
- origin = p->name;
- }
- t = strrchr(origin, '/');
- l = t ? t-origin : 0;
- p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
- if (!p->rpath) return -1;
-
- d = p->rpath;
- s = p->rpath_orig;
- while ((t=strchr(s, '$'))) {
- 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 p == MAP_FAILED ? 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;
- }
- }
-}
-
-static struct dso *load_library(const char *name, struct dso *needed_by)
-{
- char buf[2*NAME_MAX+2];
- 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;
- return 0;
- }
-
- /* Catch and block attempts to reload the implementation itself */
- if (name[0]=='l' && name[1]=='i' && name[2]=='b') {
- static const char *rp, reserved[] =
- "c\0pthread\0rt\0m\0dl\0util\0xnet\0";
- char *z = strchr(name, '.');
- if (z) {
- size_t l = z-name;
- for (rp=reserved; *rp && strncmp(name+3, rp, l-3); rp+=strlen(rp)+1);
- 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.next ? ldso.next : &ldso;
- }
- return &ldso;
- }
- if (strchr(name, '/')) {
- pathname = name;
- fd = open(name, O_RDONLY|O_CLOEXEC);
- } else {
- /* Search for the name to see if it's already loaded */
- for (p=head->next; p; p=p->next) {
- if (p->shortname && !strcmp(p->shortname, name)) {
- p->refcnt++;
- return p;
- }
- }
- if (strlen(name) > NAME_MAX) return 0;
- fd = -1;
- if (env_path) fd = path_open(name, env_path, buf, sizeof buf);
- for (p=needed_by; fd == -1 && p; p=p->needed_by) {
- if (fixup_rpath(p, buf, sizeof buf) < 0)
- fd = -2; /* Inhibit further search. */
- if (p->rpath)
- fd = path_open(name, p->rpath, buf, sizeof buf);
- }
- if (fd == -1) {
- if (!sys_path) {
- char *prefix = 0;
- size_t prefix_len;
- if (ldso.name[0]=='/') {
- char *s, *t, *z;
- for (s=t=z=ldso.name; *s; s++)
- if (*s=='/') z=t, t=s;
- prefix_len = z-ldso.name;
- if (prefix_len < PATH_MAX)
- prefix = ldso.name;
- }
- if (!prefix) {
- prefix = "";
- prefix_len = 0;
- }
- char etc_ldso_path[prefix_len + 1
- + sizeof "/etc/ld-musl-" LDSO_ARCH ".path"];
- snprintf(etc_ldso_path, sizeof etc_ldso_path,
- "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
- (int)prefix_len, prefix);
- FILE *f = fopen(etc_ldso_path, "rbe");
- if (f) {
- if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
- free(sys_path);
- sys_path = "";
- }
- fclose(f);
- } else if (errno != ENOENT) {
- sys_path = "";
- }
- }
- if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
- fd = path_open(name, sys_path, buf, sizeof buf);
- }
- pathname = buf;
- }
- if (fd < 0) return 0;
- if (fstat(fd, &st) < 0) {
- close(fd);
- return 0;
- }
- for (p=head->next; p; p=p->next) {
- if (p->dev == st.st_dev && p->ino == st.st_ino) {
- /* 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);
- p->refcnt++;
- return p;
- }
- }
- map = noload ? 0 : map_library(fd, &temp_dso);
- close(fd);
- if (!map) return 0;
-
- /* 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);
- decode_dyn(p);
- p->dev = st.st_dev;
- p->ino = st.st_ino;
- p->refcnt = 1;
- p->needed_by = needed_by;
- p->name = p->buf;
- 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 + ( (tls_align-1) &
- -(tls_offset + (uintptr_t)p->tls.image) );
- 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;
-
- if (DL_FDPIC) makefuncdescs(p);
-
- if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
-
- return p;
-}
-
-static void load_deps(struct dso *p)
-{
- size_t i, ndeps=0;
- struct dso ***deps = &p->deps, **tmp, *dep;
- for (; p; p=p->next) {
- for (i=0; p->dynv[i]; i+=2) {
- if (p->dynv[i] != DT_NEEDED) continue;
- dep = load_library(p->strings + p->dynv[i+1], p);
- 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;
- }
- if (runtime) {
- tmp = realloc(*deps, sizeof(*tmp)*(ndeps+2));
- if (!tmp) longjmp(*rtld_fail, 1);
- tmp[ndeps++] = dep;
- tmp[ndeps] = 0;
- *deps = tmp;
- }
- }
- }
-}
-
-static void load_preload(char *s)
-{
- 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;
- load_library(s, 0);
- *z = tmp;
- }
-}
-
-static void make_global(struct dso *p)
-{
- for (; p; p=p->next) p->global = 1;
-}
-
-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] = sym-p->syms << 8 | 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 &&
- mprotect(laddr(p, p->relro_start), p->relro_end-p->relro_start, PROT_READ)
- && errno != ENOSYS) {
- 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;
- }
- 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];
- for (p=fini_head; p; p=p->fini_next) {
- 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 void do_init_fini(struct dso *p)
-{
- size_t dyn[DYN_CNT];
- int need_locking = libc.threads_minus_1;
- /* Allow recursive calls that arise when a library calls
- * dlopen from one of its constructors, but block any
- * other threads until all ctors have finished. */
- if (need_locking) pthread_mutex_lock(&init_fini_lock);
- for (; p; p=p->prev) {
- if (p->constructed) continue;
- p->constructed = 1;
- 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;
- }
-#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++)();
- }
- if (!need_locking && libc.threads_minus_1) {
- need_locking = 1;
- pthread_mutex_lock(&init_fini_lock);
- }
- }
- if (need_locking) pthread_mutex_unlock(&init_fini_lock);
-}
-
-void __libc_start_init(void)
-{
- do_init_fini(tail);
-}
-
-static void dl_debug_state(void)
-{
-}
-
-weak_alias(dl_debug_state, _dl_debug_state);
-
-void __init_tls(size_t *auxv)
-{
-}
-
-__attribute__((__visibility__("hidden")))
-void *__tls_get_new(size_t *v)
-{
- pthread_t self = __pthread_self();
-
- /* Block signals to make accessing new TLS async-signal-safe */
- sigset_t set;
- __block_all_sigs(&set);
- if (v[0]<=(size_t)self->dtv[0]) {
- __restore_sigs(&set);
- return (char *)self->dtv[v[0]]+v[1]+DTP_OFFSET;
- }
-
- /* This is safe without any locks held because, if the caller
- * is able to request the Nth entry of the DTV, the DSO list
- * must be valid at least that far out and it was synchronized
- * at program startup or by an already-completed call to dlopen. */
- struct dso *p;
- for (p=head; p->tls_id != v[0]; p=p->next);
-
- /* Get new DTV space from new DSO if needed */
- if (v[0] > (size_t)self->dtv[0]) {
- void **newdtv = p->new_dtv +
- (v[0]+1)*a_fetch_add(&p->new_dtv_idx,1);
- memcpy(newdtv, self->dtv,
- ((size_t)self->dtv[0]+1) * sizeof(void *));
- newdtv[0] = (void *)v[0];
- self->dtv = self->dtv_copy = newdtv;
- }
-
- /* Get new TLS memory from all new DSOs up to the requested one */
- unsigned char *mem;
- for (p=head; ; p=p->next) {
- if (!p->tls_id || self->dtv[p->tls_id]) continue;
- mem = p->new_tls + (p->tls.size + p->tls.align)
- * a_fetch_add(&p->new_tls_idx,1);
- mem += ((uintptr_t)p->tls.image - (uintptr_t)mem)
- & (p->tls.align-1);
- self->dtv[p->tls_id] = mem;
- memcpy(mem, p->tls.image, p->tls.len);
- if (p->tls_id == v[0]) break;
- }
- __restore_sigs(&set);
- return mem + v[1] + DTP_OFFSET;
-}
-
-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);
-}
-
-/* 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. */
-
-__attribute__((__visibility__("hidden")))
-void __dls2(unsigned char *base, size_t *sp)
-{
- if (DL_FDPIC) {
- void *p1 = (void *)sp[-2];
- void *p2 = (void *)sp[-1];
- if (!p1) {
- size_t *auxv, aux[AUX_CNT];
- for (auxv=sp+1+*sp+1; *auxv; auxv++); auxv++;
- 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.global = 1;
- 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-3, __dls3, looking it up
- * symbolically as a barrier against moving the address
- * load across the above relocation processing. */
- struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
- if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp);
- else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp);
-}
-
-/* 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. */
-
-_Noreturn void __dls3(size_t *sp)
-{
- static struct dso app, vdso;
- size_t aux[AUX_CNT], *auxv;
- size_t i;
- char *env_preload=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;
- for (i=argc+1; argv[i]; i++);
- libc.auxv = auxv = (void *)(argv+i+1);
- decode_vec(auxv, aux, AUX_CNT);
- __hwcap = aux[AT_HWCAP];
- 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]);
-
- /* 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. */
- libc.tls_size = sizeof builtin_tls;
- libc.tls_align = tls_align;
- if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
- a_crash();
- }
-
- /* 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))
- && strncmp((char *)aux[AT_EXECFN], "/proc/", 6))
- 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 {
- 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_get_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);
- }
- runtime = 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);
- }
- runtime = 0;
- 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 = &app.tls;
- app.tls_id = tls_cnt = 1;
-#ifdef TLS_ABOVE_TP
- app.tls.offset = 0;
- tls_offset = app.tls.size
- + ( -((uintptr_t)app.tls.image + app.tls.size)
- & (app.tls.align-1) );
-#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);
- }
- app.global = 1;
- 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;
- }
-
- /* Attach to vdso, if provided by the kernel */
- if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {
- 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.global = 1;
- vdso.relocated = 1;
- decode_dyn(&vdso);
- vdso.prev = &ldso;
- ldso.next = &vdso;
- }
-
- /* Initial dso chain consists only of the app. */
- head = tail = &app;
-
- /* Donate unused parts of app and library mapping to malloc */
- reclaim_gaps(&app);
- reclaim_gaps(&ldso);
-
- /* Load preload/needed libraries, add their symbols to the global
- * namespace, and perform all remaining relocations. */
- if (env_preload) load_preload(env_preload);
- load_deps(&app);
- make_global(&app);
-
-#ifndef DYNAMIC_IS_RO
- for (i=0; app.dynv[i]; i+=2)
- if (app.dynv[i]==DT_DEBUG)
- app.dynv[i+1] = (size_t)&debug;
-#endif
-
- /* The main program must be relocated LAST since it may contin
- * copy relocations which depend on libraries' relocations. */
- reloc_all(app.next);
- reloc_all(&app);
-
- update_tls_size();
- if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
- void *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);
- }
- 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;
- }
- static_tls_cnt = tls_cnt;
-
- if (ldso_fail) _exit(127);
- if (ldd_mode) _exit(0);
-
- /* 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();
-
- errno = 0;
-
- CRTJMP((void *)aux[AT_ENTRY], argv-1);
- for(;;);
-}
-
-void *dlopen(const char *file, int mode)
-{
- struct dso *volatile p, *orig_tail, *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;
-
- if (!file) return head;
-
- pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
- pthread_rwlock_wrlock(&lock);
- __inhibit_ptc();
-
- p = 0;
- orig_tls_tail = tls_tail;
- orig_tls_cnt = tls_cnt;
- orig_tls_offset = tls_offset;
- orig_tls_align = tls_align;
- orig_tail = tail;
- noload = mode & RTLD_NOLOAD;
-
- rtld_fail = &jb;
- if (setjmp(*rtld_fail)) {
- /* Clean up anything new that was (partially) loaded */
- if (p && p->deps) for (i=0; p->deps[i]; i++)
- if (p->deps[i]->global < 0)
- p->deps[i]->global = 0;
- 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);
- unmap_library(p);
- free(p);
- }
- if (!orig_tls_tail) libc.tls_head = 0;
- tls_tail = orig_tls_tail;
- tls_cnt = orig_tls_cnt;
- tls_offset = orig_tls_offset;
- tls_align = orig_tls_align;
- tail = orig_tail;
- tail->next = 0;
- p = 0;
- goto end;
- } else p = load_library(file, head);
-
- if (!p) {
- error(noload ?
- "Library %s is not already loaded" :
- "Error loading shared library %s: %m",
- file);
- goto end;
- }
-
- /* First load handling */
- if (!p->deps) {
- load_deps(p);
- if (p->deps) for (i=0; p->deps[i]; i++)
- if (!p->deps[i]->global)
- p->deps[i]->global = -1;
- if (!p->global) p->global = -1;
- reloc_all(p);
- if (p->deps) for (i=0; p->deps[i]; i++)
- if (p->deps[i]->global < 0)
- p->deps[i]->global = 0;
- if (p->global < 0) p->global = 0;
- }
-
- if (mode & RTLD_GLOBAL) {
- if (p->deps) for (i=0; p->deps[i]; i++)
- p->deps[i]->global = 1;
- p->global = 1;
- }
-
- update_tls_size();
- _dl_debug_state();
- orig_tail = tail;
-end:
- __release_ptc();
- if (p) gencnt++;
- pthread_rwlock_unlock(&lock);
- if (p) do_init_fini(orig_tail);
- pthread_setcancelstate(cs, 0);
- return p;
-}
-
-__attribute__((__visibility__("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
- < p->loadmap->segs[i].p_memsz)
- return p;
- }
- } else {
- if (a-(size_t)p->map < p->map_len)
- return p;
- }
- }
- return 0;
-}
-
-void *__tls_get_addr(size_t *);
-
-static void *do_dlsym(struct dso *p, const char *s, void *ra)
-{
- size_t i;
- uint32_t h = 0, gh = 0, *ght;
- Sym *sym;
- if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) {
- if (p == RTLD_DEFAULT) {
- p = head;
- } else if (p == RTLD_NEXT) {
- p = addr2dso((size_t)ra);
- if (!p) p=head;
- p = p->next;
- }
- struct symdef def = find_sym(p, s, 0);
- if (!def.sym) goto failed;
- if ((def.sym->st_info&0xf) == STT_TLS)
- return __tls_get_addr((size_t []){def.dso->tls_id, def.sym->st_value});
- 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);
- }
- if (__dl_invalid_handle(p))
- return 0;
- if ((ght = p->ghashtab)) {
- gh = gnu_hash(s);
- sym = gnu_lookup(gh, ght, p, s);
- } else {
- h = sysv_hash(s);
- sym = sysv_lookup(s, h, p);
- }
- if (sym && (sym->st_info&0xf) == STT_TLS)
- return __tls_get_addr((size_t []){p->tls_id, sym->st_value});
- if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)
- return p->funcdescs + (sym - p->syms);
- if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
- return laddr(p, sym->st_value);
- if (p->deps) for (i=0; p->deps[i]; i++) {
- if ((ght = p->deps[i]->ghashtab)) {
- if (!gh) gh = gnu_hash(s);
- sym = gnu_lookup(gh, ght, p->deps[i], s);
- } else {
- if (!h) h = sysv_hash(s);
- sym = sysv_lookup(s, h, p->deps[i]);
- }
- if (sym && (sym->st_info&0xf) == STT_TLS)
- return __tls_get_addr((size_t []){p->deps[i]->tls_id, sym->st_value});
- if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC)
- return p->deps[i]->funcdescs + (sym - p->deps[i]->syms);
- if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
- return laddr(p->deps[i], sym->st_value);
- }
-failed:
- error("Symbol not found: %s", s);
- return 0;
-}
-
-int dladdr(const void *addr, Dl_info *info)
-{
- struct dso *p;
- Sym *sym, *bestsym;
- uint32_t nsym;
- char *strings;
- void *best = 0;
-
- pthread_rwlock_rdlock(&lock);
- p = addr2dso((size_t)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 = ((size_t)addr-(size_t)p->funcdescs)
- / sizeof(*p->funcdescs);
- if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
- best = p->funcdescs + idx;
- bestsym = sym + idx;
- }
- }
-
- if (!best) for (; nsym; nsym--, sym++) {
- if (sym->st_value
- && (1<<(sym->st_info&0xf) & OK_TYPES)
- && (1<<(sym->st_info>>4) & OK_BINDS)) {
- void *symaddr = laddr(p, sym->st_value);
- if (symaddr > addr || symaddr < best)
- continue;
- best = symaddr;
- bestsym = sym;
- if (addr == symaddr)
- break;
- }
- }
-
- if (!best) return 0;
-
- if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
- best = p->funcdescs + (bestsym - p->syms);
-
- info->dli_fname = p->name;
- info->dli_fbase = p->base;
- info->dli_sname = strings + bestsym->st_name;
- info->dli_saddr = best;
-
- return 1;
-}
-
-__attribute__((__visibility__("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;
-}
-
-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;
-}
-
-__attribute__((__visibility__("hidden")))
-void __dl_vseterr(const char *, va_list);
-
-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);
-}
-#endif
-#ifdef SHARED
-
#include <stddef.h>
#include "libc.h"
}
weak_alias(__tlsdesc_static, __tlsdesc_dynamic);
-
-#endif
projects / oweals / musl.git / commitdiff