summaryrefslogtreecommitdiffstats
path: root/libc-top-half/musl/ldso/dynlink.c
diff options
context:
space:
mode:
Diffstat (limited to 'libc-top-half/musl/ldso/dynlink.c')
-rw-r--r--libc-top-half/musl/ldso/dynlink.c2361
1 files changed, 2361 insertions, 0 deletions
diff --git a/libc-top-half/musl/ldso/dynlink.c b/libc-top-half/musl/ldso/dynlink.c
new file mode 100644
index 0000000..5b9c8be
--- /dev/null
+++ b/libc-top-half/musl/ldso/dynlink.c
@@ -0,0 +1,2361 @@
+#define _GNU_SOURCE
+#define SYSCALL_NO_TLS 1
+#include <stdlib.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <string.h>
+#include <unistd.h>
+#include <stdint.h>
+#include <elf.h>
+#include <sys/mman.h>
+#include <limits.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <link.h>
+#include <setjmp.h>
+#include <pthread.h>
+#include <ctype.h>
+#include <dlfcn.h>
+#include <semaphore.h>
+#include <sys/membarrier.h>
+#include "pthread_impl.h"
+#include "fork_impl.h"
+#include "libc.h"
+#include "dynlink.h"
+
+#define malloc __libc_malloc
+#define calloc __libc_calloc
+#define realloc __libc_realloc
+#define free __libc_free
+
+static void error(const char *, ...);
+
+#define MAXP2(a,b) (-(-(a)&-(b)))
+#define ALIGN(x,y) ((x)+(y)-1 & -(y))
+
+#define container_of(p,t,m) ((t*)((char *)(p)-offsetof(t,m)))
+#define countof(a) ((sizeof (a))/(sizeof (a)[0]))
+
+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;
+ Sym *syms;
+ Elf_Symndx *hashtab;
+ uint32_t *ghashtab;
+ int16_t *versym;
+ char *strings;
+ struct dso *syms_next, *lazy_next;
+ size_t *lazy, lazy_cnt;
+ unsigned char *map;
+ size_t map_len;
+ dev_t dev;
+ ino_t ino;
+ char relocated;
+ char constructed;
+ char kernel_mapped;
+ char mark;
+ char bfs_built;
+ char runtime_loaded;
+ struct dso **deps, *needed_by;
+ size_t ndeps_direct;
+ size_t next_dep;
+ pthread_t ctor_visitor;
+ char *rpath_orig, *rpath;
+ struct tls_module tls;
+ size_t tls_id;
+ size_t relro_start, relro_end;
+ uintptr_t *new_dtv;
+ unsigned char *new_tls;
+ struct td_index *td_index;
+ struct dso *fini_next;
+ char *shortname;
+#if DL_FDPIC
+ unsigned char *base;
+#else
+ struct fdpic_loadmap *loadmap;
+#endif
+ struct funcdesc {
+ void *addr;
+ size_t *got;
+ } *funcdescs;
+ size_t *got;
+ char buf[];
+};
+
+struct symdef {
+ Sym *sym;
+ struct dso *dso;
+};
+
+typedef void (*stage3_func)(size_t *, size_t *);
+
+static struct builtin_tls {
+ 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, *syms_tail, *lazy_head;
+static char *env_path, *sys_path;
+static unsigned long long gencnt;
+static int runtime;
+static int ldd_mode;
+static int ldso_fail;
+static int noload;
+static int shutting_down;
+static jmp_buf *rtld_fail;
+static pthread_rwlock_t lock;
+static struct debug debug;
+static struct tls_module *tls_tail;
+static size_t tls_cnt, tls_offset, tls_align = MIN_TLS_ALIGN;
+static size_t static_tls_cnt;
+static pthread_mutex_t init_fini_lock;
+static pthread_cond_t ctor_cond;
+static struct dso *builtin_deps[2];
+static struct dso *const no_deps[1];
+static struct dso *builtin_ctor_queue[4];
+static struct dso **main_ctor_queue;
+static struct fdpic_loadmap *app_loadmap;
+static struct fdpic_dummy_loadmap app_dummy_loadmap;
+
+struct debug *_dl_debug_addr = &debug;
+
+extern hidden int __malloc_replaced;
+
+hidden void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0;
+
+extern hidden void (*const __init_array_end)(void), (*const __fini_array_end)(void);
+
+weak_alias(__init_array_start, __init_array_end);
+weak_alias(__fini_array_start, __fini_array_end);
+
+static int dl_strcmp(const char *l, const char *r)
+{
+ for (; *l==*r && *l; l++, r++);
+ return *(unsigned char *)l - *(unsigned char *)r;
+}
+#define strcmp(l,r) dl_strcmp(l,r)
+
+/* Compute load address for a virtual address in a given dso. */
+#if DL_FDPIC
+static void *laddr(const struct dso *p, size_t v)
+{
+ size_t j=0;
+ if (!p->loadmap) return p->base + v;
+ for (j=0; v-p->loadmap->segs[j].p_vaddr >= p->loadmap->segs[j].p_memsz; j++);
+ return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
+}
+static void *laddr_pg(const struct dso *p, size_t v)
+{
+ size_t j=0;
+ size_t pgsz = PAGE_SIZE;
+ if (!p->loadmap) return p->base + v;
+ for (j=0; ; j++) {
+ size_t a = p->loadmap->segs[j].p_vaddr;
+ size_t b = a + p->loadmap->segs[j].p_memsz;
+ a &= -pgsz;
+ b += pgsz-1;
+ b &= -pgsz;
+ if (v-a<b-a) break;
+ }
+ return (void *)(v - p->loadmap->segs[j].p_vaddr + p->loadmap->segs[j].addr);
+}
+static void (*fdbarrier(void *p))()
+{
+ void (*fd)();
+ __asm__("" : "=r"(fd) : "0"(p));
+ return fd;
+}
+#define fpaddr(p, v) fdbarrier((&(struct funcdesc){ \
+ laddr(p, v), (p)->got }))
+#else
+#define laddr(p, v) (void *)((p)->base + (v))
+#define laddr_pg(p, v) laddr(p, v)
+#define fpaddr(p, v) ((void (*)())laddr(p, v))
+#endif
+
+static void decode_vec(size_t *v, size_t *a, size_t cnt)
+{
+ size_t i;
+ for (i=0; i<cnt; i++) a[i] = 0;
+ for (; v[0]; v+=2) if (v[0]-1<cnt-1) {
+ a[0] |= 1UL<<v[0];
+ a[v[0]] = v[1];
+ }
+}
+
+static int search_vec(size_t *v, size_t *r, size_t key)
+{
+ for (; v[0]!=key; v+=2)
+ if (!v[0]) return 0;
+ *r = v[1];
+ return 1;
+}
+
+static uint32_t sysv_hash(const char *s0)
+{
+ const unsigned char *s = (void *)s0;
+ uint_fast32_t h = 0;
+ while (*s) {
+ h = 16*h + *s++;
+ h ^= h>>24 & 0xf0;
+ }
+ return h & 0xfffffff;
+}
+
+static uint32_t gnu_hash(const char *s0)
+{
+ const unsigned char *s = (void *)s0;
+ uint_fast32_t h = 5381;
+ for (; *s; s++)
+ h += h*32 + *s;
+ return h;
+}
+
+static Sym *sysv_lookup(const char *s, uint32_t h, struct dso *dso)
+{
+ size_t i;
+ Sym *syms = dso->syms;
+ Elf_Symndx *hashtab = dso->hashtab;
+ char *strings = dso->strings;
+ for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
+ if ((!dso->versym || dso->versym[i] >= 0)
+ && (!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
+
+#if defined(__GNUC__)
+__attribute__((always_inline))
+#endif
+static inline struct symdef find_sym2(struct dso *dso, const char *s, int need_def, int use_deps)
+{
+ uint32_t h = 0, gh = gnu_hash(s), gho = gh / (8*sizeof(size_t)), *ght;
+ size_t ghm = 1ul << gh % (8*sizeof(size_t));
+ struct symdef def = {0};
+ struct dso **deps = use_deps ? dso->deps : 0;
+ for (; dso; dso=use_deps ? *deps++ : dso->syms_next) {
+ Sym *sym;
+ if ((ght = dso->ghashtab)) {
+ sym = gnu_lookup_filtered(gh, ght, dso, s, gho, ghm);
+ } else {
+ if (!h) h = sysv_hash(s);
+ sym = sysv_lookup(s, h, dso);
+ }
+ if (!sym) continue;
+ if (!sym->st_shndx)
+ if (need_def || (sym->st_info&0xf) == STT_TLS
+ || 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;
+ def.sym = sym;
+ def.dso = dso;
+ break;
+ }
+ return def;
+}
+
+static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
+{
+ return find_sym2(dso, s, need_def, 0);
+}
+
+static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
+{
+ unsigned char *base = dso->base;
+ Sym *syms = dso->syms;
+ char *strings = dso->strings;
+ Sym *sym;
+ const char *name;
+ void *ctx;
+ int type;
+ int sym_index;
+ struct symdef def;
+ size_t *reloc_addr;
+ size_t sym_val;
+ size_t tls_val;
+ size_t addend;
+ int skip_relative = 0, reuse_addends = 0, save_slot = 0;
+
+ if (dso == &ldso) {
+ /* Only ldso's REL table needs addend saving/reuse. */
+ if (rel == apply_addends_to)
+ reuse_addends = 1;
+ skip_relative = 1;
+ }
+
+ for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
+ if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue;
+ type = R_TYPE(rel[1]);
+ if (type == REL_NONE) continue;
+ reloc_addr = laddr(dso, rel[0]);
+
+ if (stride > 2) {
+ addend = rel[2];
+ } else if (type==REL_GOT || type==REL_PLT|| type==REL_COPY) {
+ addend = 0;
+ } else if (reuse_addends) {
+ /* Save original addend in stage 2 where the dso
+ * chain consists of just ldso; otherwise read back
+ * saved addend since the inline one was clobbered. */
+ if (head==&ldso)
+ saved_addends[save_slot] = *reloc_addr;
+ addend = saved_addends[save_slot++];
+ } else {
+ addend = *reloc_addr;
+ }
+
+ sym_index = R_SYM(rel[1]);
+ if (sym_index) {
+ sym = syms + sym_index;
+ name = strings + sym->st_name;
+ ctx = type==REL_COPY ? head->syms_next : head;
+ def = (sym->st_info>>4) == STB_LOCAL
+ ? (struct symdef){ .dso = dso, .sym = sym }
+ : find_sym(ctx, name, type==REL_PLT);
+ if (!def.sym && (sym->st_shndx != SHN_UNDEF
+ || sym->st_info>>4 != STB_WEAK)) {
+ if (dso->lazy && (type==REL_PLT || type==REL_GOT)) {
+ dso->lazy[3*dso->lazy_cnt+0] = rel[0];
+ dso->lazy[3*dso->lazy_cnt+1] = rel[1];
+ dso->lazy[3*dso->lazy_cnt+2] = addend;
+ dso->lazy_cnt++;
+ continue;
+ }
+ error("Error relocating %s: %s: symbol not found",
+ dso->name, name);
+ if (runtime) longjmp(*rtld_fail, 1);
+ continue;
+ }
+ } else {
+ sym = 0;
+ def.sym = 0;
+ def.dso = dso;
+ }
+
+ sym_val = def.sym ? (size_t)laddr(def.dso, def.sym->st_value) : 0;
+ tls_val = def.sym ? def.sym->st_value : 0;
+
+ if ((type == REL_TPOFF || type == REL_TPOFF_NEG)
+ && def.dso->tls_id > static_tls_cnt) {
+ error("Error relocating %s: %s: initial-exec TLS "
+ "resolves to dynamic definition in %s",
+ dso->name, name, def.dso->name);
+ longjmp(*rtld_fail, 1);
+ }
+
+ switch(type) {
+ case REL_OFFSET:
+ addend -= (size_t)reloc_addr;
+ case REL_SYMBOLIC:
+ case REL_GOT:
+ case REL_PLT:
+ *reloc_addr = sym_val + addend;
+ break;
+ case REL_USYMBOLIC:
+ memcpy(reloc_addr, &(size_t){sym_val + addend}, sizeof(size_t));
+ break;
+ case REL_RELATIVE:
+ *reloc_addr = (size_t)base + addend;
+ break;
+ case REL_SYM_OR_REL:
+ if (sym) *reloc_addr = sym_val + addend;
+ else *reloc_addr = (size_t)base + addend;
+ break;
+ case REL_COPY:
+ memcpy(reloc_addr, (void *)sym_val, sym->st_size);
+ break;
+ case REL_OFFSET32:
+ *(uint32_t *)reloc_addr = sym_val + addend
+ - (size_t)reloc_addr;
+ break;
+ case REL_FUNCDESC:
+ *reloc_addr = def.sym ? (size_t)(def.dso->funcdescs
+ + (def.sym - def.dso->syms)) : 0;
+ break;
+ case REL_FUNCDESC_VAL:
+ if ((sym->st_info&0xf) == STT_SECTION) *reloc_addr += sym_val;
+ else *reloc_addr = sym_val;
+ reloc_addr[1] = def.sym ? (size_t)def.dso->got : 0;
+ break;
+ case REL_DTPMOD:
+ *reloc_addr = def.dso->tls_id;
+ break;
+ case REL_DTPOFF:
+ *reloc_addr = tls_val + addend - DTP_OFFSET;
+ break;
+#ifdef TLS_ABOVE_TP
+ case REL_TPOFF:
+ *reloc_addr = tls_val + def.dso->tls.offset + TPOFF_K + addend;
+ break;
+#else
+ case REL_TPOFF:
+ *reloc_addr = tls_val - def.dso->tls.offset + addend;
+ break;
+ case REL_TPOFF_NEG:
+ *reloc_addr = def.dso->tls.offset - tls_val + addend;
+ break;
+#endif
+ case REL_TLSDESC:
+ if (stride<3) addend = reloc_addr[1];
+ if (def.dso->tls_id > static_tls_cnt) {
+ struct td_index *new = malloc(sizeof *new);
+ if (!new) {
+ error(
+ "Error relocating %s: cannot allocate TLSDESC for %s",
+ dso->name, sym ? name : "(local)" );
+ longjmp(*rtld_fail, 1);
+ }
+ new->next = dso->td_index;
+ dso->td_index = new;
+ new->args[0] = def.dso->tls_id;
+ new->args[1] = tls_val + addend - DTP_OFFSET;
+ reloc_addr[0] = (size_t)__tlsdesc_dynamic;
+ reloc_addr[1] = (size_t)new;
+ } else {
+ reloc_addr[0] = (size_t)__tlsdesc_static;
+#ifdef TLS_ABOVE_TP
+ reloc_addr[1] = tls_val + def.dso->tls.offset
+ + TPOFF_K + addend;
+#else
+ reloc_addr[1] = tls_val - def.dso->tls.offset
+ + addend;
+#endif
+ }
+#ifdef TLSDESC_BACKWARDS
+ /* Some archs (32-bit ARM at least) invert the order of
+ * the descriptor members. Fix them up here. */
+ size_t tmp = reloc_addr[0];
+ reloc_addr[0] = reloc_addr[1];
+ reloc_addr[1] = tmp;
+#endif
+ break;
+ default:
+ error("Error relocating %s: unsupported relocation type %d",
+ dso->name, type);
+ if (runtime) longjmp(*rtld_fail, 1);
+ continue;
+ }
+ }
+}
+
+static void redo_lazy_relocs()
+{
+ struct dso *p = lazy_head, *next;
+ lazy_head = 0;
+ for (; p; p=next) {
+ next = p->lazy_next;
+ size_t size = p->lazy_cnt*3*sizeof(size_t);
+ p->lazy_cnt = 0;
+ do_relocs(p, p->lazy, size, 3);
+ if (p->lazy_cnt) {
+ p->lazy_next = lazy_head;
+ lazy_head = p;
+ } else {
+ free(p->lazy);
+ p->lazy = 0;
+ p->lazy_next = 0;
+ }
+ }
+}
+
+/* A huge hack: to make up for the wastefulness of shared libraries
+ * needing at least a page of dirty memory even if they have no global
+ * data, we reclaim the gaps at the beginning and end of writable maps
+ * and "donate" them to the heap. */
+
+static void reclaim(struct dso *dso, size_t start, size_t end)
+{
+ if (start >= dso->relro_start && start < dso->relro_end) start = dso->relro_end;
+ if (end >= dso->relro_start && end < dso->relro_end) end = dso->relro_start;
+ if (start >= end) return;
+ char *base = laddr_pg(dso, start);
+ __malloc_donate(base, base+(end-start));
+}
+
+static void reclaim_gaps(struct dso *dso)
+{
+ Phdr *ph = dso->phdr;
+ size_t phcnt = dso->phnum;
+
+ for (; phcnt--; ph=(void *)((char *)ph+dso->phentsize)) {
+ if (ph->p_type!=PT_LOAD) continue;
+ if ((ph->p_flags&(PF_R|PF_W))!=(PF_R|PF_W)) continue;
+ reclaim(dso, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
+ reclaim(dso, ph->p_vaddr+ph->p_memsz,
+ ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE);
+ }
+}
+
+static ssize_t read_loop(int fd, void *p, size_t n)
+{
+ for (size_t i=0; i<n; ) {
+ ssize_t l = read(fd, (char *)p+i, n-i);
+ if (l<0) {
+ if (errno==EINTR) continue;
+ else return -1;
+ }
+ if (l==0) return i;
+ i += l;
+ }
+ return n;
+}
+
+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 (!n) return p;
+ if (!no_map_fixed) {
+ q = mmap(p, n, prot, flags|MAP_FIXED, fd, off);
+ if (!DL_NOMMU_SUPPORT || q != MAP_FAILED || errno != EINVAL)
+ return q;
+ no_map_fixed = 1;
+ }
+ /* Fallbacks for MAP_FIXED failure on NOMMU kernels. */
+ if (flags & MAP_ANONYMOUS) {
+ memset(p, 0, n);
+ return p;
+ }
+ ssize_t r;
+ if (lseek(fd, off, SEEK_SET) < 0) return MAP_FAILED;
+ for (q=p; n; q+=r, off+=r, n-=r) {
+ r = read(fd, q, n);
+ if (r < 0 && errno != EINTR) return MAP_FAILED;
+ if (!r) {
+ memset(q, 0, n);
+ break;
+ }
+ }
+ return p;
+}
+
+static void unmap_library(struct dso *dso)
+{
+ if (dso->loadmap) {
+ size_t i;
+ for (i=0; i<dso->loadmap->nsegs; i++) {
+ if (!dso->loadmap->segs[i].p_memsz)
+ continue;
+ munmap((void *)dso->loadmap->segs[i].addr,
+ dso->loadmap->segs[i].p_memsz);
+ }
+ free(dso->loadmap);
+ } else if (dso->map && dso->map_len) {
+ munmap(dso->map, dso->map_len);
+ }
+}
+
+static void *map_library(int fd, struct dso *dso)
+{
+ Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
+ void *allocated_buf=0;
+ size_t phsize;
+ size_t addr_min=SIZE_MAX, addr_max=0, map_len;
+ size_t this_min, this_max;
+ size_t nsegs = 0;
+ off_t off_start;
+ Ehdr *eh;
+ Phdr *ph, *ph0;
+ unsigned prot;
+ unsigned char *map=MAP_FAILED, *base;
+ size_t dyn=0;
+ size_t tls_image=0;
+ size_t i;
+
+ ssize_t l = read(fd, buf, sizeof buf);
+ eh = buf;
+ if (l<0) return 0;
+ if (l<sizeof *eh || (eh->e_type != ET_DYN && eh->e_type != ET_EXEC))
+ goto noexec;
+ phsize = eh->e_phentsize * eh->e_phnum;
+ if (phsize > sizeof buf - sizeof *eh) {
+ allocated_buf = malloc(phsize);
+ if (!allocated_buf) return 0;
+ l = pread(fd, allocated_buf, phsize, eh->e_phoff);
+ if (l < 0) goto error;
+ if (l != phsize) goto noexec;
+ ph = ph0 = allocated_buf;
+ } else if (eh->e_phoff + phsize > l) {
+ l = pread(fd, buf+1, phsize, eh->e_phoff);
+ if (l < 0) goto error;
+ if (l != phsize) goto noexec;
+ ph = ph0 = (void *)(buf + 1);
+ } else {
+ ph = ph0 = (void *)((char *)buf + eh->e_phoff);
+ }
+ for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
+ if (ph->p_type == PT_DYNAMIC) {
+ dyn = ph->p_vaddr;
+ } else if (ph->p_type == PT_TLS) {
+ tls_image = ph->p_vaddr;
+ dso->tls.align = ph->p_align;
+ dso->tls.len = ph->p_filesz;
+ dso->tls.size = ph->p_memsz;
+ } else if (ph->p_type == PT_GNU_RELRO) {
+ dso->relro_start = ph->p_vaddr & -PAGE_SIZE;
+ dso->relro_end = (ph->p_vaddr + ph->p_memsz) & -PAGE_SIZE;
+ } else if (ph->p_type == PT_GNU_STACK) {
+ if (!runtime && ph->p_memsz > __default_stacksize) {
+ __default_stacksize =
+ ph->p_memsz < DEFAULT_STACK_MAX ?
+ ph->p_memsz : DEFAULT_STACK_MAX;
+ }
+ }
+ if (ph->p_type != PT_LOAD) continue;
+ nsegs++;
+ if (ph->p_vaddr < addr_min) {
+ addr_min = ph->p_vaddr;
+ off_start = ph->p_offset;
+ prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
+ ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
+ ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
+ }
+ if (ph->p_vaddr+ph->p_memsz > addr_max) {
+ addr_max = ph->p_vaddr+ph->p_memsz;
+ }
+ }
+ if (!dyn) goto noexec;
+ if (DL_FDPIC && !(eh->e_flags & FDPIC_CONSTDISP_FLAG)) {
+ dso->loadmap = calloc(1, sizeof *dso->loadmap
+ + nsegs * sizeof *dso->loadmap->segs);
+ if (!dso->loadmap) goto error;
+ dso->loadmap->nsegs = nsegs;
+ for (ph=ph0, i=0; i<nsegs; ph=(void *)((char *)ph+eh->e_phentsize)) {
+ if (ph->p_type != PT_LOAD) continue;
+ prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
+ ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
+ ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
+ map = mmap(0, ph->p_memsz + (ph->p_vaddr & PAGE_SIZE-1),
+ prot, MAP_PRIVATE,
+ fd, ph->p_offset & -PAGE_SIZE);
+ if (map == MAP_FAILED) {
+ unmap_library(dso);
+ goto error;
+ }
+ dso->loadmap->segs[i].addr = (size_t)map +
+ (ph->p_vaddr & PAGE_SIZE-1);
+ dso->loadmap->segs[i].p_vaddr = ph->p_vaddr;
+ dso->loadmap->segs[i].p_memsz = ph->p_memsz;
+ i++;
+ if (prot & PROT_WRITE) {
+ size_t brk = (ph->p_vaddr & PAGE_SIZE-1)
+ + ph->p_filesz;
+ size_t pgbrk = brk + PAGE_SIZE-1 & -PAGE_SIZE;
+ size_t pgend = brk + ph->p_memsz - ph->p_filesz
+ + PAGE_SIZE-1 & -PAGE_SIZE;
+ if (pgend > pgbrk && mmap_fixed(map+pgbrk,
+ pgend-pgbrk, prot,
+ MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS,
+ -1, off_start) == MAP_FAILED)
+ goto error;
+ memset(map + brk, 0, pgbrk-brk);
+ }
+ }
+ map = (void *)dso->loadmap->segs[0].addr;
+ map_len = 0;
+ goto done_mapping;
+ }
+ addr_max += PAGE_SIZE-1;
+ addr_max &= -PAGE_SIZE;
+ addr_min &= -PAGE_SIZE;
+ off_start &= -PAGE_SIZE;
+ map_len = addr_max - addr_min + off_start;
+ /* The first time, we map too much, possibly even more than
+ * the length of the file. This is okay because we will not
+ * use the invalid part; we just need to reserve the right
+ * amount of virtual address space to map over later. */
+ map = DL_NOMMU_SUPPORT
+ ? mmap((void *)addr_min, map_len, PROT_READ|PROT_WRITE|PROT_EXEC,
+ MAP_PRIVATE|MAP_ANONYMOUS, -1, 0)
+ : mmap((void *)addr_min, map_len, prot,
+ MAP_PRIVATE, fd, off_start);
+ if (map==MAP_FAILED) goto error;
+ dso->map = map;
+ dso->map_len = map_len;
+ /* If the loaded file is not relocatable and the requested address is
+ * not available, then the load operation must fail. */
+ if (eh->e_type != ET_DYN && addr_min && map!=(void *)addr_min) {
+ errno = EBUSY;
+ goto error;
+ }
+ base = map - addr_min;
+ dso->phdr = 0;
+ dso->phnum = 0;
+ for (ph=ph0, i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
+ if (ph->p_type != PT_LOAD) continue;
+ /* Check if the programs headers are in this load segment, and
+ * if so, record the address for use by dl_iterate_phdr. */
+ if (!dso->phdr && eh->e_phoff >= ph->p_offset
+ && 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;
+ }
+ this_min = ph->p_vaddr & -PAGE_SIZE;
+ this_max = ph->p_vaddr+ph->p_memsz+PAGE_SIZE-1 & -PAGE_SIZE;
+ off_start = ph->p_offset & -PAGE_SIZE;
+ prot = (((ph->p_flags&PF_R) ? PROT_READ : 0) |
+ ((ph->p_flags&PF_W) ? PROT_WRITE: 0) |
+ ((ph->p_flags&PF_X) ? PROT_EXEC : 0));
+ /* Reuse the existing mapping for the lowest-address LOAD */
+ if ((ph->p_vaddr & -PAGE_SIZE) != addr_min || DL_NOMMU_SUPPORT)
+ if (mmap_fixed(base+this_min, this_max-this_min, prot, MAP_PRIVATE|MAP_FIXED, fd, off_start) == MAP_FAILED)
+ goto error;
+ if (ph->p_memsz > ph->p_filesz && (ph->p_flags&PF_W)) {
+ size_t brk = (size_t)base+ph->p_vaddr+ph->p_filesz;
+ size_t pgbrk = brk+PAGE_SIZE-1 & -PAGE_SIZE;
+ memset((void *)brk, 0, pgbrk-brk & PAGE_SIZE-1);
+ if (pgbrk-(size_t)base < this_max && mmap_fixed((void *)pgbrk, (size_t)base+this_max-pgbrk, prot, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) == MAP_FAILED)
+ goto error;
+ }
+ }
+ for (i=0; ((size_t *)(base+dyn))[i]; i+=2)
+ if (((size_t *)(base+dyn))[i]==DT_TEXTREL) {
+ if (mprotect(map, map_len, PROT_READ|PROT_WRITE|PROT_EXEC)
+ && 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);
+ free(allocated_buf);
+ return map;
+noexec:
+ errno = ENOEXEC;
+error:
+ if (map!=MAP_FAILED) unmap_library(dso);
+ free(allocated_buf);
+ return 0;
+}
+
+static int path_open(const char *name, const char *s, char *buf, size_t buf_size)
+{
+ size_t l;
+ int fd;
+ for (;;) {
+ s += strspn(s, ":\n");
+ l = strcspn(s, ":\n");
+ if (l-1 >= INT_MAX) return -1;
+ if (snprintf(buf, buf_size, "%.*s/%s", (int)l, s, name) < buf_size) {
+ if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
+ switch (errno) {
+ case ENOENT:
+ case ENOTDIR:
+ case EACCES:
+ case ENAMETOOLONG:
+ break;
+ default:
+ /* Any negative value but -1 will inhibit
+ * futher path search. */
+ return -2;
+ }
+ }
+ s += l;
+ }
+}
+
+static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
+{
+ size_t n, l;
+ const char *s, *t, *origin;
+ char *d;
+ if (p->rpath || !p->rpath_orig) return 0;
+ if (!strchr(p->rpath_orig, '$')) {
+ p->rpath = p->rpath_orig;
+ return 0;
+ }
+ n = 0;
+ s = p->rpath_orig;
+ while ((t=strchr(s, '$'))) {
+ if (strncmp(t, "$ORIGIN", 7) && strncmp(t, "${ORIGIN}", 9))
+ return 0;
+ s = t+1;
+ n++;
+ }
+ if (n > SSIZE_MAX/PATH_MAX) return 0;
+
+ if (p->kernel_mapped) {
+ /* $ORIGIN searches cannot be performed for the main program
+ * when it is suid/sgid/AT_SECURE. This is because the
+ * pathname is under the control of the caller of execve.
+ * For libraries, however, $ORIGIN can be processed safely
+ * since the library's pathname came from a trusted source
+ * (either system paths or a call to dlopen). */
+ if (libc.secure)
+ return 0;
+ l = readlink("/proc/self/exe", buf, buf_size);
+ if (l == -1) switch (errno) {
+ case ENOENT:
+ case ENOTDIR:
+ case EACCES:
+ break;
+ default:
+ return -1;
+ }
+ if (l >= buf_size)
+ return 0;
+ buf[l] = 0;
+ origin = buf;
+ } else {
+ origin = p->name;
+ }
+ t = strrchr(origin, '/');
+ if (t) {
+ l = t-origin;
+ } else {
+ /* Normally p->name will always be an absolute or relative
+ * pathname containing at least one '/' character, but in the
+ * case where ldso was invoked as a command to execute a
+ * program in the working directory, app.name may not. Fix. */
+ origin = ".";
+ l = 1;
+ }
+ /* Disallow non-absolute origins for suid/sgid/AT_SECURE. */
+ if (libc.secure && *origin != '/')
+ return 0;
+ p->rpath = malloc(strlen(p->rpath_orig) + n*l + 1);
+ if (!p->rpath) return -1;
+
+ d = p->rpath;
+ s = p->rpath_orig;
+ while ((t=strchr(s, '$'))) {
+ memcpy(d, s, t-s);
+ d += t-s;
+ memcpy(d, origin, l);
+ d += l;
+ /* It was determined previously that the '$' is followed
+ * either by "ORIGIN" or "{ORIGIN}". */
+ s = t + 7 + 2*(t[1]=='{');
+ }
+ strcpy(d, s);
+ return 0;
+}
+
+static void decode_dyn(struct dso *p)
+{
+ size_t dyn[DYN_CNT];
+ decode_vec(p->dynv, dyn, DYN_CNT);
+ p->syms = laddr(p, dyn[DT_SYMTAB]);
+ p->strings = laddr(p, dyn[DT_STRTAB]);
+ if (dyn[0]&(1<<DT_HASH))
+ p->hashtab = laddr(p, dyn[DT_HASH]);
+ if (dyn[0]&(1<<DT_RPATH))
+ p->rpath_orig = p->strings + dyn[DT_RPATH];
+ if (dyn[0]&(1<<DT_RUNPATH))
+ p->rpath_orig = p->strings + dyn[DT_RUNPATH];
+ if (dyn[0]&(1<<DT_PLTGOT))
+ p->got = laddr(p, dyn[DT_PLTGOT]);
+ if (search_vec(p->dynv, dyn, DT_GNU_HASH))
+ p->ghashtab = laddr(p, *dyn);
+ if (search_vec(p->dynv, dyn, DT_VERSYM))
+ p->versym = laddr(p, *dyn);
+}
+
+static size_t count_syms(struct dso *p)
+{
+ if (p->hashtab) return p->hashtab[1];
+
+ size_t nsym, i;
+ uint32_t *buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
+ uint32_t *hashval;
+ for (i = nsym = 0; i < p->ghashtab[0]; i++) {
+ if (buckets[i] > nsym)
+ nsym = buckets[i];
+ }
+ if (nsym) {
+ hashval = buckets + p->ghashtab[0] + (nsym - p->ghashtab[1]);
+ do nsym++;
+ while (!(*hashval++ & 1));
+ }
+ return nsym;
+}
+
+static void *dl_mmap(size_t n)
+{
+ void *p;
+ int prot = PROT_READ|PROT_WRITE, flags = MAP_ANONYMOUS|MAP_PRIVATE;
+#ifdef SYS_mmap2
+ p = (void *)__syscall(SYS_mmap2, 0, n, prot, flags, -1, 0);
+#else
+ p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0);
+#endif
+ return (unsigned long)p > -4096UL ? 0 : p;
+}
+
+static void makefuncdescs(struct dso *p)
+{
+ static int self_done;
+ size_t nsym = count_syms(p);
+ size_t i, size = nsym * sizeof(*p->funcdescs);
+
+ if (!self_done) {
+ p->funcdescs = dl_mmap(size);
+ self_done = 1;
+ } else {
+ p->funcdescs = malloc(size);
+ }
+ if (!p->funcdescs) {
+ if (!runtime) a_crash();
+ error("Error allocating function descriptors for %s", p->name);
+ longjmp(*rtld_fail, 1);
+ }
+ for (i=0; i<nsym; i++) {
+ if ((p->syms[i].st_info&0xf)==STT_FUNC && p->syms[i].st_shndx) {
+ p->funcdescs[i].addr = laddr(p, p->syms[i].st_value);
+ p->funcdescs[i].got = p->got;
+ } else {
+ p->funcdescs[i].addr = 0;
+ p->funcdescs[i].got = 0;
+ }
+ }
+}
+
+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 reserved[] =
+ "c.pthread.rt.m.dl.util.xnet.";
+ const char *rp, *next;
+ for (rp=reserved; *rp; rp=next) {
+ next = strchr(rp, '.') + 1;
+ if (strncmp(name+3, rp, next-rp) == 0)
+ break;
+ }
+ if (*rp) {
+ if (ldd_mode) {
+ /* Track which names have been resolved
+ * and only report each one once. */
+ static unsigned reported;
+ unsigned mask = 1U<<(rp-reserved);
+ if (!(reported & mask)) {
+ reported |= mask;
+ dprintf(1, "\t%s => %s (%p)\n",
+ name, ldso.name,
+ ldso.base);
+ }
+ }
+ is_self = 1;
+ }
+ }
+ if (!strcmp(name, ldso.name)) is_self = 1;
+ if (is_self) {
+ if (!ldso.prev) {
+ tail->next = &ldso;
+ ldso.prev = tail;
+ tail = &ldso;
+ }
+ 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)) {
+ 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);
+ fd = open(etc_ldso_path, O_RDONLY|O_CLOEXEC);
+ if (fd>=0) {
+ size_t n = 0;
+ if (!fstat(fd, &st)) n = st.st_size;
+ if ((sys_path = malloc(n+1)))
+ sys_path[n] = 0;
+ if (!sys_path || read_loop(fd, sys_path, n)<0) {
+ free(sys_path);
+ sys_path = "";
+ }
+ close(fd);
+ } 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);
+ return p;
+ }
+ }
+ map = noload ? 0 : map_library(fd, &temp_dso);
+ close(fd);
+ if (!map) return 0;
+
+ /* Avoid the danger of getting two versions of libc mapped into the
+ * same process when an absolute pathname was used. The symbols
+ * checked are chosen to catch both musl and glibc, and to avoid
+ * false positives from interposition-hack libraries. */
+ decode_dyn(&temp_dso);
+ if (find_sym(&temp_dso, "__libc_start_main", 1).sym &&
+ find_sym(&temp_dso, "stdin", 1).sym) {
+ unmap_library(&temp_dso);
+ return load_library("libc.so", needed_by);
+ }
+ /* Past this point, if we haven't reached runtime yet, ldso has
+ * committed either to use the mapped library or to abort execution.
+ * Unmapping is not possible, so we can safely reclaim gaps. */
+ if (!runtime) reclaim_gaps(&temp_dso);
+
+ /* Allocate storage for the new DSO. When there is TLS, this
+ * storage must include a reservation for all pre-existing
+ * threads to obtain copies of both the new TLS, and an
+ * extended DTV capable of storing an additional slot for
+ * the newly-loaded DSO. */
+ alloc_size = sizeof *p + strlen(pathname) + 1;
+ if (runtime && temp_dso.tls.image) {
+ size_t per_th = temp_dso.tls.size + temp_dso.tls.align
+ + sizeof(void *) * (tls_cnt+3);
+ n_th = libc.threads_minus_1 + 1;
+ if (n_th > SSIZE_MAX / per_th) alloc_size = SIZE_MAX;
+ else alloc_size += n_th * per_th;
+ }
+ p = calloc(1, alloc_size);
+ if (!p) {
+ unmap_library(&temp_dso);
+ return 0;
+ }
+ memcpy(p, &temp_dso, sizeof temp_dso);
+ p->dev = st.st_dev;
+ p->ino = st.st_ino;
+ p->needed_by = needed_by;
+ p->name = p->buf;
+ p->runtime_loaded = runtime;
+ strcpy(p->name, pathname);
+ /* Add a shortname only if name arg was not an explicit pathname. */
+ if (pathname != name) p->shortname = strrchr(p->name, '/')+1;
+ if (p->tls.image) {
+ p->tls_id = ++tls_cnt;
+ tls_align = MAXP2(tls_align, p->tls.align);
+#ifdef TLS_ABOVE_TP
+ p->tls.offset = tls_offset + ( (p->tls.align-1) &
+ (-tls_offset + (uintptr_t)p->tls.image) );
+ tls_offset = p->tls.offset + p->tls.size;
+#else
+ tls_offset += p->tls.size + p->tls.align - 1;
+ tls_offset -= (tls_offset + (uintptr_t)p->tls.image)
+ & (p->tls.align-1);
+ p->tls.offset = tls_offset;
+#endif
+ p->new_dtv = (void *)(-sizeof(size_t) &
+ (uintptr_t)(p->name+strlen(p->name)+sizeof(size_t)));
+ p->new_tls = (void *)(p->new_dtv + n_th*(tls_cnt+1));
+ if (tls_tail) tls_tail->next = &p->tls;
+ else libc.tls_head = &p->tls;
+ tls_tail = &p->tls;
+ }
+
+ tail->next = p;
+ p->prev = tail;
+ tail = p;
+
+ if (DL_FDPIC) makefuncdescs(p);
+
+ if (ldd_mode) dprintf(1, "\t%s => %s (%p)\n", name, pathname, p->base);
+
+ return p;
+}
+
+static void load_direct_deps(struct dso *p)
+{
+ size_t i, cnt=0;
+
+ if (p->deps) return;
+ /* For head, all preloads are direct pseudo-dependencies.
+ * Count and include them now to avoid realloc later. */
+ if (p==head) for (struct dso *q=p->next; q; q=q->next)
+ cnt++;
+ for (i=0; p->dynv[i]; i+=2)
+ if (p->dynv[i] == DT_NEEDED) cnt++;
+ /* Use builtin buffer for apps with no external deps, to
+ * preserve property of no runtime failure paths. */
+ p->deps = (p==head && cnt<2) ? builtin_deps :
+ calloc(cnt+1, sizeof *p->deps);
+ if (!p->deps) {
+ error("Error loading dependencies for %s", p->name);
+ if (runtime) longjmp(*rtld_fail, 1);
+ }
+ cnt=0;
+ if (p==head) for (struct dso *q=p->next; q; q=q->next)
+ p->deps[cnt++] = q;
+ for (i=0; p->dynv[i]; i+=2) {
+ if (p->dynv[i] != DT_NEEDED) continue;
+ struct dso *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;
+ }
+ p->deps[cnt++] = dep;
+ }
+ p->deps[cnt] = 0;
+ p->ndeps_direct = cnt;
+}
+
+static void load_deps(struct dso *p)
+{
+ if (p->deps) return;
+ for (; p; p=p->next)
+ load_direct_deps(p);
+}
+
+static void extend_bfs_deps(struct dso *p)
+{
+ size_t i, j, cnt, ndeps_all;
+ struct dso **tmp;
+
+ /* Can't use realloc if the original p->deps was allocated at
+ * program entry and malloc has been replaced, or if it's
+ * the builtin non-allocated trivial main program deps array. */
+ int no_realloc = (__malloc_replaced && !p->runtime_loaded)
+ || p->deps == builtin_deps;
+
+ if (p->bfs_built) return;
+ ndeps_all = p->ndeps_direct;
+
+ /* Mark existing (direct) deps so they won't be duplicated. */
+ for (i=0; p->deps[i]; i++)
+ p->deps[i]->mark = 1;
+
+ /* For each dependency already in the list, copy its list of direct
+ * dependencies to the list, excluding any items already in the
+ * list. Note that the list this loop iterates over will grow during
+ * the loop, but since duplicates are excluded, growth is bounded. */
+ for (i=0; p->deps[i]; i++) {
+ struct dso *dep = p->deps[i];
+ for (j=cnt=0; j<dep->ndeps_direct; j++)
+ if (!dep->deps[j]->mark) cnt++;
+ tmp = no_realloc ?
+ malloc(sizeof(*tmp) * (ndeps_all+cnt+1)) :
+ realloc(p->deps, sizeof(*tmp) * (ndeps_all+cnt+1));
+ if (!tmp) {
+ error("Error recording dependencies for %s", p->name);
+ if (runtime) longjmp(*rtld_fail, 1);
+ continue;
+ }
+ if (no_realloc) {
+ memcpy(tmp, p->deps, sizeof(*tmp) * (ndeps_all+1));
+ no_realloc = 0;
+ }
+ p->deps = tmp;
+ for (j=0; j<dep->ndeps_direct; j++) {
+ if (dep->deps[j]->mark) continue;
+ dep->deps[j]->mark = 1;
+ p->deps[ndeps_all++] = dep->deps[j];
+ }
+ p->deps[ndeps_all] = 0;
+ }
+ p->bfs_built = 1;
+ for (p=head; p; p=p->next)
+ p->mark = 0;
+}
+
+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 add_syms(struct dso *p)
+{
+ if (!p->syms_next && syms_tail != p) {
+ syms_tail->syms_next = p;
+ syms_tail = p;
+ }
+}
+
+static void revert_syms(struct dso *old_tail)
+{
+ struct dso *p, *next;
+ /* Chop off the tail of the list of dsos that participate in
+ * the global symbol table, reverting them to RTLD_LOCAL. */
+ for (p=old_tail; p; p=next) {
+ next = p->syms_next;
+ p->syms_next = 0;
+ }
+ syms_tail = old_tail;
+}
+
+static void do_mips_relocs(struct dso *p, size_t *got)
+{
+ size_t i, j, rel[2];
+ unsigned char *base = p->base;
+ i=0; search_vec(p->dynv, &i, DT_MIPS_LOCAL_GOTNO);
+ if (p==&ldso) {
+ got += i;
+ } else {
+ while (i--) *got++ += (size_t)base;
+ }
+ j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
+ i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
+ Sym *sym = p->syms + j;
+ rel[0] = (unsigned char *)got - base;
+ for (i-=j; i; i--, sym++, rel[0]+=sizeof(size_t)) {
+ rel[1] = R_INFO(sym-p->syms, R_MIPS_JUMP_SLOT);
+ do_relocs(p, rel, sizeof rel, 2);
+ }
+}
+
+static void reloc_all(struct dso *p)
+{
+ size_t dyn[DYN_CNT];
+ for (; p; p=p->next) {
+ if (p->relocated) continue;
+ decode_vec(p->dynv, dyn, DYN_CNT);
+ if (NEED_MIPS_GOT_RELOCS)
+ do_mips_relocs(p, laddr(p, dyn[DT_PLTGOT]));
+ do_relocs(p, laddr(p, dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
+ 2+(dyn[DT_PLTREL]==DT_RELA));
+ do_relocs(p, laddr(p, dyn[DT_REL]), dyn[DT_RELSZ], 2);
+ do_relocs(p, laddr(p, dyn[DT_RELA]), dyn[DT_RELASZ], 3);
+
+ if (head != &ldso && p->relro_start != p->relro_end &&
+ 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;
+ } else if (ph->p_type == PT_GNU_STACK) {
+ if (!runtime && ph->p_memsz > __default_stacksize) {
+ __default_stacksize =
+ ph->p_memsz < DEFAULT_STACK_MAX ?
+ ph->p_memsz : DEFAULT_STACK_MAX;
+ }
+ }
+ if (ph->p_type != PT_LOAD) continue;
+ if (ph->p_vaddr < min_addr)
+ min_addr = ph->p_vaddr;
+ if (ph->p_vaddr+ph->p_memsz > max_addr)
+ max_addr = ph->p_vaddr+ph->p_memsz;
+ }
+ min_addr &= -PAGE_SIZE;
+ max_addr = (max_addr + PAGE_SIZE-1) & -PAGE_SIZE;
+ p->map = p->base + min_addr;
+ p->map_len = max_addr - min_addr;
+ p->kernel_mapped = 1;
+}
+
+void __libc_exit_fini()
+{
+ struct dso *p;
+ size_t dyn[DYN_CNT];
+ pthread_t self = __pthread_self();
+
+ /* Take both locks before setting shutting_down, so that
+ * either lock is sufficient to read its value. The lock
+ * order matches that in dlopen to avoid deadlock. */
+ pthread_rwlock_wrlock(&lock);
+ pthread_mutex_lock(&init_fini_lock);
+ shutting_down = 1;
+ pthread_rwlock_unlock(&lock);
+ for (p=fini_head; p; p=p->fini_next) {
+ while (p->ctor_visitor && p->ctor_visitor!=self)
+ pthread_cond_wait(&ctor_cond, &init_fini_lock);
+ if (!p->constructed) continue;
+ decode_vec(p->dynv, dyn, DYN_CNT);
+ if (dyn[0] & (1<<DT_FINI_ARRAY)) {
+ size_t n = dyn[DT_FINI_ARRAYSZ]/sizeof(size_t);
+ size_t *fn = (size_t *)laddr(p, dyn[DT_FINI_ARRAY])+n;
+ while (n--) ((void (*)(void))*--fn)();
+ }
+#ifndef NO_LEGACY_INITFINI
+ if ((dyn[0] & (1<<DT_FINI)) && dyn[DT_FINI])
+ fpaddr(p, dyn[DT_FINI])();
+#endif
+ }
+}
+
+void __ldso_atfork(int who)
+{
+ if (who<0) {
+ pthread_rwlock_wrlock(&lock);
+ pthread_mutex_lock(&init_fini_lock);
+ } else {
+ pthread_mutex_unlock(&init_fini_lock);
+ pthread_rwlock_unlock(&lock);
+ }
+}
+
+static struct dso **queue_ctors(struct dso *dso)
+{
+ size_t cnt, qpos, spos, i;
+ struct dso *p, **queue, **stack;
+
+ if (ldd_mode) return 0;
+
+ /* Bound on queue size is the total number of indirect deps.
+ * If a bfs deps list was built, we can use it. Otherwise,
+ * bound by the total number of DSOs, which is always safe and
+ * is reasonable we use it (for main app at startup). */
+ if (dso->bfs_built) {
+ for (cnt=0; dso->deps[cnt]; cnt++)
+ dso->deps[cnt]->mark = 0;
+ cnt++; /* self, not included in deps */
+ } else {
+ for (cnt=0, p=head; p; cnt++, p=p->next)
+ p->mark = 0;
+ }
+ cnt++; /* termination slot */
+ if (dso==head && cnt <= countof(builtin_ctor_queue))
+ queue = builtin_ctor_queue;
+ else
+ queue = calloc(cnt, sizeof *queue);
+
+ if (!queue) {
+ error("Error allocating constructor queue: %m\n");
+ if (runtime) longjmp(*rtld_fail, 1);
+ return 0;
+ }
+
+ /* Opposite ends of the allocated buffer serve as an output queue
+ * and a working stack. Setup initial stack with just the argument
+ * dso and initial queue empty... */
+ stack = queue;
+ qpos = 0;
+ spos = cnt;
+ stack[--spos] = dso;
+ dso->next_dep = 0;
+ dso->mark = 1;
+
+ /* Then perform pseudo-DFS sort, but ignoring circular deps. */
+ while (spos<cnt) {
+ p = stack[spos++];
+ while (p->next_dep < p->ndeps_direct) {
+ if (p->deps[p->next_dep]->mark) {
+ p->next_dep++;
+ } else {
+ stack[--spos] = p;
+ p = p->deps[p->next_dep];
+ p->next_dep = 0;
+ p->mark = 1;
+ }
+ }
+ queue[qpos++] = p;
+ }
+ queue[qpos] = 0;
+ for (i=0; i<qpos; i++) queue[i]->mark = 0;
+ for (i=0; i<qpos; i++)
+ if (queue[i]->ctor_visitor && queue[i]->ctor_visitor->tid < 0) {
+ error("State of %s is inconsistent due to multithreaded fork\n",
+ queue[i]->name);
+ free(queue);
+ if (runtime) longjmp(*rtld_fail, 1);
+ }
+
+ return queue;
+}
+
+static void do_init_fini(struct dso **queue)
+{
+ struct dso *p;
+ size_t dyn[DYN_CNT], i;
+ pthread_t self = __pthread_self();
+
+ pthread_mutex_lock(&init_fini_lock);
+ for (i=0; (p=queue[i]); i++) {
+ while ((p->ctor_visitor && p->ctor_visitor!=self) || shutting_down)
+ pthread_cond_wait(&ctor_cond, &init_fini_lock);
+ if (p->ctor_visitor || p->constructed)
+ continue;
+ p->ctor_visitor = self;
+
+ decode_vec(p->dynv, dyn, DYN_CNT);
+ if (dyn[0] & ((1<<DT_FINI) | (1<<DT_FINI_ARRAY))) {
+ p->fini_next = fini_head;
+ fini_head = p;
+ }
+
+ pthread_mutex_unlock(&init_fini_lock);
+
+#ifndef NO_LEGACY_INITFINI
+ if ((dyn[0] & (1<<DT_INIT)) && dyn[DT_INIT])
+ fpaddr(p, dyn[DT_INIT])();
+#endif
+ if (dyn[0] & (1<<DT_INIT_ARRAY)) {
+ size_t n = dyn[DT_INIT_ARRAYSZ]/sizeof(size_t);
+ size_t *fn = laddr(p, dyn[DT_INIT_ARRAY]);
+ while (n--) ((void (*)(void))*fn++)();
+ }
+
+ pthread_mutex_lock(&init_fini_lock);
+ p->ctor_visitor = 0;
+ p->constructed = 1;
+ pthread_cond_broadcast(&ctor_cond);
+ }
+ pthread_mutex_unlock(&init_fini_lock);
+}
+
+void __libc_start_init(void)
+{
+ do_init_fini(main_ctor_queue);
+ if (!__malloc_replaced && main_ctor_queue != builtin_ctor_queue)
+ free(main_ctor_queue);
+ main_ctor_queue = 0;
+}
+
+static void dl_debug_state(void)
+{
+}
+
+weak_alias(dl_debug_state, _dl_debug_state);
+
+void __init_tls(size_t *auxv)
+{
+}
+
+static void update_tls_size()
+{
+ libc.tls_cnt = tls_cnt;
+ libc.tls_align = tls_align;
+ libc.tls_size = ALIGN(
+ (1+tls_cnt) * sizeof(void *) +
+ tls_offset +
+ sizeof(struct pthread) +
+ tls_align * 2,
+ tls_align);
+}
+
+static void install_new_tls(void)
+{
+ sigset_t set;
+ pthread_t self = __pthread_self(), td;
+ struct dso *dtv_provider = container_of(tls_tail, struct dso, tls);
+ uintptr_t (*newdtv)[tls_cnt+1] = (void *)dtv_provider->new_dtv;
+ struct dso *p;
+ size_t i, j;
+ size_t old_cnt = self->dtv[0];
+
+ __block_app_sigs(&set);
+ __tl_lock();
+ /* Copy existing dtv contents from all existing threads. */
+ for (i=0, td=self; !i || td!=self; i++, td=td->next) {
+ memcpy(newdtv+i, td->dtv,
+ (old_cnt+1)*sizeof(uintptr_t));
+ newdtv[i][0] = tls_cnt;
+ }
+ /* Install new dtls into the enlarged, uninstalled dtv copies. */
+ for (p=head; ; p=p->next) {
+ if (p->tls_id <= old_cnt) continue;
+ unsigned char *mem = p->new_tls;
+ for (j=0; j<i; j++) {
+ unsigned char *new = mem;
+ new += ((uintptr_t)p->tls.image - (uintptr_t)mem)
+ & (p->tls.align-1);
+ memcpy(new, p->tls.image, p->tls.len);
+ newdtv[j][p->tls_id] =
+ (uintptr_t)new + DTP_OFFSET;
+ mem += p->tls.size + p->tls.align;
+ }
+ if (p->tls_id == tls_cnt) break;
+ }
+
+ /* Broadcast barrier to ensure contents of new dtv is visible
+ * if the new dtv pointer is. The __membarrier function has a
+ * fallback emulation using signals for kernels that lack the
+ * feature at the syscall level. */
+
+ __membarrier(MEMBARRIER_CMD_PRIVATE_EXPEDITED, 0);
+
+ /* Install new dtv for each thread. */
+ for (j=0, td=self; !j || td!=self; j++, td=td->next) {
+ td->dtv = newdtv[j];
+ }
+
+ __tl_unlock();
+ __restore_sigs(&set);
+}
+
+/* Stage 1 of the dynamic linker is defined in dlstart.c. It calls the
+ * following stage 2 and stage 3 functions via primitive symbolic lookup
+ * since it does not have access to their addresses to begin with. */
+
+/* Stage 2 of the dynamic linker is called after relative relocations
+ * have been processed. It can make function calls to static functions
+ * and access string literals and static data, but cannot use extern
+ * symbols. Its job is to perform symbolic relocations on the dynamic
+ * linker itself, but some of the relocations performed may need to be
+ * replaced later due to copy relocations in the main program. */
+
+hidden void __dls2(unsigned char *base, size_t *sp)
+{
+ size_t *auxv;
+ for (auxv=sp+1+*sp+1; *auxv; auxv++);
+ auxv++;
+ if (DL_FDPIC) {
+ void *p1 = (void *)sp[-2];
+ void *p2 = (void *)sp[-1];
+ if (!p1) {
+ size_t aux[AUX_CNT];
+ decode_vec(auxv, aux, AUX_CNT);
+ if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];
+ else ldso.base = (void *)(aux[AT_PHDR] & -4096);
+ }
+ app_loadmap = p2 ? p1 : 0;
+ ldso.loadmap = p2 ? p2 : p1;
+ ldso.base = laddr(&ldso, 0);
+ } else {
+ ldso.base = base;
+ }
+ Ehdr *ehdr = (void *)ldso.base;
+ ldso.name = ldso.shortname = "libc.so";
+ ldso.phnum = ehdr->e_phnum;
+ ldso.phdr = laddr(&ldso, ehdr->e_phoff);
+ ldso.phentsize = ehdr->e_phentsize;
+ kernel_mapped_dso(&ldso);
+ decode_dyn(&ldso);
+
+ if (DL_FDPIC) makefuncdescs(&ldso);
+
+ /* Prepare storage for to save clobbered REL addends so they
+ * can be reused in stage 3. There should be very few. If
+ * something goes wrong and there are a huge number, abort
+ * instead of risking stack overflow. */
+ size_t dyn[DYN_CNT];
+ decode_vec(ldso.dynv, dyn, DYN_CNT);
+ size_t *rel = laddr(&ldso, dyn[DT_REL]);
+ size_t rel_size = dyn[DT_RELSZ];
+ size_t symbolic_rel_cnt = 0;
+ apply_addends_to = rel;
+ for (; rel_size; rel+=2, rel_size-=2*sizeof(size_t))
+ if (!IS_RELATIVE(rel[1], ldso.syms)) symbolic_rel_cnt++;
+ if (symbolic_rel_cnt >= ADDEND_LIMIT) a_crash();
+ size_t addends[symbolic_rel_cnt+1];
+ saved_addends = addends;
+
+ head = &ldso;
+ reloc_all(&ldso);
+
+ ldso.relocated = 0;
+
+ /* Call dynamic linker stage-2b, __dls2b, looking it up
+ * symbolically as a barrier against moving the address
+ * load across the above relocation processing. */
+ struct symdef dls2b_def = find_sym(&ldso, "__dls2b", 0);
+ if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls2b_def.sym-ldso.syms])(sp, auxv);
+ else ((stage3_func)laddr(&ldso, dls2b_def.sym->st_value))(sp, auxv);
+}
+
+/* Stage 2b sets up a valid thread pointer, which requires relocations
+ * completed in stage 2, and on which stage 3 is permitted to depend.
+ * This is done as a separate stage, with symbolic lookup as a barrier,
+ * so that loads of the thread pointer and &errno can be pure/const and
+ * thereby hoistable. */
+
+void __dls2b(size_t *sp, size_t *auxv)
+{
+ /* Setup early thread pointer in builtin_tls for ldso/libc itself to
+ * use during dynamic linking. If possible it will also serve as the
+ * thread pointer at runtime. */
+ search_vec(auxv, &__hwcap, AT_HWCAP);
+ libc.auxv = auxv;
+ libc.tls_size = sizeof builtin_tls;
+ libc.tls_align = tls_align;
+ if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
+ a_crash();
+ }
+
+ struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
+ if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp, auxv);
+ else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp, auxv);
+}
+
+/* Stage 3 of the dynamic linker is called with the dynamic linker/libc
+ * fully functional. Its job is to load (if not already loaded) and
+ * process dependencies and relocations for the main application and
+ * transfer control to its entry point. */
+
+void __dls3(size_t *sp, size_t *auxv)
+{
+ static struct dso app, vdso;
+ size_t aux[AUX_CNT];
+ size_t i;
+ char *env_preload=0;
+ char *replace_argv0=0;
+ size_t vdso_base;
+ int argc = *sp;
+ char **argv = (void *)(sp+1);
+ char **argv_orig = argv;
+ char **envp = argv+argc+1;
+
+ /* Find aux vector just past environ[] and use it to initialize
+ * global data that may be needed before we can make syscalls. */
+ __environ = envp;
+ decode_vec(auxv, aux, AUX_CNT);
+ search_vec(auxv, &__sysinfo, AT_SYSINFO);
+ __pthread_self()->sysinfo = __sysinfo;
+ libc.page_size = aux[AT_PAGESZ];
+ libc.secure = ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
+ || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]);
+
+ /* Only trust user/env if kernel says we're not suid/sgid */
+ if (!libc.secure) {
+ env_path = getenv("LD_LIBRARY_PATH");
+ env_preload = getenv("LD_PRELOAD");
+ }
+
+ /* If the main program was already loaded by the kernel,
+ * AT_PHDR will point to some location other than the dynamic
+ * linker's program headers. */
+ if (aux[AT_PHDR] != (size_t)ldso.phdr) {
+ size_t interp_off = 0;
+ size_t tls_image = 0;
+ /* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
+ Phdr *phdr = app.phdr = (void *)aux[AT_PHDR];
+ app.phnum = aux[AT_PHNUM];
+ app.phentsize = aux[AT_PHENT];
+ for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
+ if (phdr->p_type == PT_PHDR)
+ app.base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
+ else if (phdr->p_type == PT_INTERP)
+ interp_off = (size_t)phdr->p_vaddr;
+ else if (phdr->p_type == PT_TLS) {
+ tls_image = phdr->p_vaddr;
+ app.tls.len = phdr->p_filesz;
+ app.tls.size = phdr->p_memsz;
+ app.tls.align = phdr->p_align;
+ }
+ }
+ if (DL_FDPIC) app.loadmap = app_loadmap;
+ if (app.tls.size) app.tls.image = laddr(&app, tls_image);
+ if (interp_off) ldso.name = laddr(&app, interp_off);
+ if ((aux[0] & (1UL<<AT_EXECFN))
+ && 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 if (!memcmp(opt, "argv0", 5)) {
+ if (opt[5]=='=') replace_argv0 = opt+6;
+ else if (opt[5]) *argv = 0;
+ else if (*argv) replace_argv0 = *argv++;
+ } else {
+ argv[0] = 0;
+ }
+ }
+ argv[-1] = (void *)(argc - (argv-argv_orig));
+ if (!argv[0]) {
+ dprintf(2, "musl libc (" LDSO_ARCH ")\n"
+ "Version %s\n"
+ "Dynamic Program Loader\n"
+ "Usage: %s [options] [--] pathname%s\n",
+ __libc_version, ldname,
+ ldd_mode ? "" : " [args]");
+ _exit(1);
+ }
+ fd = open(argv[0], O_RDONLY);
+ if (fd < 0) {
+ dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
+ _exit(1);
+ }
+ Ehdr *ehdr = map_library(fd, &app);
+ if (!ehdr) {
+ dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
+ _exit(1);
+ }
+ close(fd);
+ ldso.name = ldname;
+ app.name = argv[0];
+ aux[AT_ENTRY] = (size_t)laddr(&app, ehdr->e_entry);
+ /* Find the name that would have been used for the dynamic
+ * linker had ldd not taken its place. */
+ if (ldd_mode) {
+ for (i=0; i<app.phnum; i++) {
+ if (app.phdr[i].p_type == PT_INTERP)
+ ldso.name = laddr(&app, app.phdr[i].p_vaddr);
+ }
+ dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
+ }
+ }
+ if (app.tls.size) {
+ libc.tls_head = tls_tail = &app.tls;
+ app.tls_id = tls_cnt = 1;
+#ifdef TLS_ABOVE_TP
+ app.tls.offset = GAP_ABOVE_TP;
+ app.tls.offset += (-GAP_ABOVE_TP + (uintptr_t)app.tls.image)
+ & (app.tls.align-1);
+ tls_offset = app.tls.offset + app.tls.size;
+#else
+ tls_offset = app.tls.offset = app.tls.size
+ + ( -((uintptr_t)app.tls.image + app.tls.size)
+ & (app.tls.align-1) );
+#endif
+ tls_align = MAXP2(tls_align, app.tls.align);
+ }
+ decode_dyn(&app);
+ if (DL_FDPIC) {
+ makefuncdescs(&app);
+ if (!app.loadmap) {
+ app.loadmap = (void *)&app_dummy_loadmap;
+ app.loadmap->nsegs = 1;
+ app.loadmap->segs[0].addr = (size_t)app.map;
+ app.loadmap->segs[0].p_vaddr = (size_t)app.map
+ - (size_t)app.base;
+ app.loadmap->segs[0].p_memsz = app.map_len;
+ }
+ argv[-3] = (void *)app.loadmap;
+ }
+
+ /* Initial dso chain consists only of the app. */
+ head = tail = syms_tail = &app;
+
+ /* Donate unused parts of app and library mapping to malloc */
+ reclaim_gaps(&app);
+ reclaim_gaps(&ldso);
+
+ /* Load preload/needed libraries, add symbols to global namespace. */
+ ldso.deps = (struct dso **)no_deps;
+ if (env_preload) load_preload(env_preload);
+ load_deps(&app);
+ for (struct dso *p=head; p; p=p->next)
+ add_syms(p);
+
+ /* Attach to vdso, if provided by the kernel, last so that it does
+ * not become part of the global namespace. */
+ if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR) && vdso_base) {
+ Ehdr *ehdr = (void *)vdso_base;
+ Phdr *phdr = vdso.phdr = (void *)(vdso_base + ehdr->e_phoff);
+ vdso.phnum = ehdr->e_phnum;
+ vdso.phentsize = ehdr->e_phentsize;
+ for (i=ehdr->e_phnum; i; i--, phdr=(void *)((char *)phdr + ehdr->e_phentsize)) {
+ if (phdr->p_type == PT_DYNAMIC)
+ vdso.dynv = (void *)(vdso_base + phdr->p_offset);
+ if (phdr->p_type == PT_LOAD)
+ vdso.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
+ }
+ vdso.name = "";
+ vdso.shortname = "linux-gate.so.1";
+ vdso.relocated = 1;
+ vdso.deps = (struct dso **)no_deps;
+ decode_dyn(&vdso);
+ vdso.prev = tail;
+ tail->next = &vdso;
+ tail = &vdso;
+ }
+
+ for (i=0; app.dynv[i]; i+=2) {
+ if (!DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG)
+ app.dynv[i+1] = (size_t)&debug;
+ if (DT_DEBUG_INDIRECT && app.dynv[i]==DT_DEBUG_INDIRECT) {
+ size_t *ptr = (size_t *) app.dynv[i+1];
+ *ptr = (size_t)&debug;
+ }
+ }
+
+ /* This must be done before final relocations, since it calls
+ * malloc, which may be provided by the application. Calling any
+ * application code prior to the jump to its entry point is not
+ * valid in our model and does not work with FDPIC, where there
+ * are additional relocation-like fixups that only the entry point
+ * code can see to perform. */
+ main_ctor_queue = queue_ctors(&app);
+
+ /* Initial TLS must also be allocated before final relocations
+ * might result in calloc being a call to application code. */
+ update_tls_size();
+ void *initial_tls = builtin_tls;
+ if (libc.tls_size > sizeof builtin_tls || tls_align > MIN_TLS_ALIGN) {
+ initial_tls = calloc(libc.tls_size, 1);
+ if (!initial_tls) {
+ dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
+ argv[0], libc.tls_size);
+ _exit(127);
+ }
+ }
+ static_tls_cnt = tls_cnt;
+
+ /* The main program must be relocated LAST since it may contain
+ * copy relocations which depend on libraries' relocations. */
+ reloc_all(app.next);
+ reloc_all(&app);
+
+ /* Actual copying to new TLS needs to happen after relocations,
+ * since the TLS images might have contained relocated addresses. */
+ if (initial_tls != builtin_tls) {
+ if (__init_tp(__copy_tls(initial_tls)) < 0) {
+ a_crash();
+ }
+ } else {
+ size_t tmp_tls_size = libc.tls_size;
+ pthread_t self = __pthread_self();
+ /* Temporarily set the tls size to the full size of
+ * builtin_tls so that __copy_tls will use the same layout
+ * as it did for before. Then check, just to be safe. */
+ libc.tls_size = sizeof builtin_tls;
+ if (__copy_tls((void*)builtin_tls) != self) a_crash();
+ libc.tls_size = tmp_tls_size;
+ }
+
+ if (ldso_fail) _exit(127);
+ if (ldd_mode) _exit(0);
+
+ /* Determine if malloc was interposed by a replacement implementation
+ * so that calloc and the memalign family can harden against the
+ * possibility of incomplete replacement. */
+ if (find_sym(head, "malloc", 1).dso != &ldso)
+ __malloc_replaced = 1;
+ if (find_sym(head, "aligned_alloc", 1).dso != &ldso)
+ __aligned_alloc_replaced = 1;
+
+ /* Switch to runtime mode: any further failures in the dynamic
+ * linker are a reportable failure rather than a fatal startup
+ * error. */
+ runtime = 1;
+
+ debug.ver = 1;
+ debug.bp = dl_debug_state;
+ debug.head = head;
+ debug.base = ldso.base;
+ debug.state = RT_CONSISTENT;
+ _dl_debug_state();
+
+ if (replace_argv0) argv[0] = replace_argv0;
+
+ errno = 0;
+
+ CRTJMP((void *)aux[AT_ENTRY], argv-1);
+ for(;;);
+}
+
+static void prepare_lazy(struct dso *p)
+{
+ size_t dyn[DYN_CNT], n, flags1=0;
+ decode_vec(p->dynv, dyn, DYN_CNT);
+ search_vec(p->dynv, &flags1, DT_FLAGS_1);
+ if (dyn[DT_BIND_NOW] || (dyn[DT_FLAGS] & DF_BIND_NOW) || (flags1 & DF_1_NOW))
+ return;
+ n = dyn[DT_RELSZ]/2 + dyn[DT_RELASZ]/3 + dyn[DT_PLTRELSZ]/2 + 1;
+ if (NEED_MIPS_GOT_RELOCS) {
+ size_t j=0; search_vec(p->dynv, &j, DT_MIPS_GOTSYM);
+ size_t i=0; search_vec(p->dynv, &i, DT_MIPS_SYMTABNO);
+ n += i-j;
+ }
+ p->lazy = calloc(n, 3*sizeof(size_t));
+ if (!p->lazy) {
+ error("Error preparing lazy relocation for %s: %m", p->name);
+ longjmp(*rtld_fail, 1);
+ }
+ p->lazy_next = lazy_head;
+ lazy_head = p;
+}
+
+void *dlopen(const char *file, int mode)
+{
+ struct dso *volatile p, *orig_tail, *orig_syms_tail, *orig_lazy_head, *next;
+ struct tls_module *orig_tls_tail;
+ size_t orig_tls_cnt, orig_tls_offset, orig_tls_align;
+ size_t i;
+ int cs;
+ jmp_buf jb;
+ struct dso **volatile ctor_queue = 0;
+
+ if (!file) return head;
+
+ pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+ pthread_rwlock_wrlock(&lock);
+ __inhibit_ptc();
+
+ debug.state = RT_ADD;
+ _dl_debug_state();
+
+ p = 0;
+ if (shutting_down) {
+ error("Cannot dlopen while program is exiting.");
+ goto end;
+ }
+ orig_tls_tail = tls_tail;
+ orig_tls_cnt = tls_cnt;
+ orig_tls_offset = tls_offset;
+ orig_tls_align = tls_align;
+ orig_lazy_head = lazy_head;
+ orig_syms_tail = syms_tail;
+ orig_tail = tail;
+ noload = mode & RTLD_NOLOAD;
+
+ rtld_fail = &jb;
+ if (setjmp(*rtld_fail)) {
+ /* Clean up anything new that was (partially) loaded */
+ revert_syms(orig_syms_tail);
+ for (p=orig_tail->next; p; p=next) {
+ next = p->next;
+ while (p->td_index) {
+ void *tmp = p->td_index->next;
+ free(p->td_index);
+ p->td_index = tmp;
+ }
+ free(p->funcdescs);
+ if (p->rpath != p->rpath_orig)
+ free(p->rpath);
+ free(p->deps);
+ unmap_library(p);
+ free(p);
+ }
+ free(ctor_queue);
+ ctor_queue = 0;
+ if (!orig_tls_tail) libc.tls_head = 0;
+ tls_tail = orig_tls_tail;
+ if (tls_tail) tls_tail->next = 0;
+ tls_cnt = orig_tls_cnt;
+ tls_offset = orig_tls_offset;
+ tls_align = orig_tls_align;
+ lazy_head = orig_lazy_head;
+ tail = orig_tail;
+ tail->next = 0;
+ p = 0;
+ goto end;
+ } 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 */
+ load_deps(p);
+ extend_bfs_deps(p);
+ pthread_mutex_lock(&init_fini_lock);
+ int constructed = p->constructed;
+ pthread_mutex_unlock(&init_fini_lock);
+ if (!constructed) ctor_queue = queue_ctors(p);
+ if (!p->relocated && (mode & RTLD_LAZY)) {
+ prepare_lazy(p);
+ for (i=0; p->deps[i]; i++)
+ if (!p->deps[i]->relocated)
+ prepare_lazy(p->deps[i]);
+ }
+ if (!p->relocated || (mode & RTLD_GLOBAL)) {
+ /* Make new symbols global, at least temporarily, so we can do
+ * relocations. If not RTLD_GLOBAL, this is reverted below. */
+ add_syms(p);
+ for (i=0; p->deps[i]; i++)
+ add_syms(p->deps[i]);
+ }
+ if (!p->relocated) {
+ reloc_all(p);
+ }
+
+ /* If RTLD_GLOBAL was not specified, undo any new additions
+ * to the global symbol table. This is a nop if the library was
+ * previously loaded and already global. */
+ if (!(mode & RTLD_GLOBAL))
+ revert_syms(orig_syms_tail);
+
+ /* Processing of deferred lazy relocations must not happen until
+ * the new libraries are committed; otherwise we could end up with
+ * relocations resolved to symbol definitions that get removed. */
+ redo_lazy_relocs();
+
+ update_tls_size();
+ if (tls_cnt != orig_tls_cnt)
+ install_new_tls();
+ orig_tail = tail;
+end:
+ debug.state = RT_CONSISTENT;
+ _dl_debug_state();
+ __release_ptc();
+ if (p) gencnt++;
+ pthread_rwlock_unlock(&lock);
+ if (ctor_queue) {
+ do_init_fini(ctor_queue);
+ free(ctor_queue);
+ }
+ pthread_setcancelstate(cs, 0);
+ return p;
+}
+
+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 {
+ Phdr *ph = p->phdr;
+ size_t phcnt = p->phnum;
+ size_t entsz = p->phentsize;
+ size_t base = (size_t)p->base;
+ for (; phcnt--; ph=(void *)((char *)ph+entsz)) {
+ if (ph->p_type != PT_LOAD) continue;
+ if (a-base-ph->p_vaddr < ph->p_memsz)
+ return p;
+ }
+ if (a-(size_t)p->map < p->map_len)
+ return 0;
+ }
+ }
+ return 0;
+}
+
+static void *do_dlsym(struct dso *p, const char *s, void *ra)
+{
+ int use_deps = 0;
+ if (p == head || p == RTLD_DEFAULT) {
+ p = head;
+ } else if (p == RTLD_NEXT) {
+ p = addr2dso((size_t)ra);
+ if (!p) p=head;
+ p = p->next;
+ } else if (__dl_invalid_handle(p)) {
+ return 0;
+ } else
+ use_deps = 1;
+ struct symdef def = find_sym2(p, s, 0, use_deps);
+ if (!def.sym) {
+ error("Symbol not found: %s", s);
+ return 0;
+ }
+ if ((def.sym->st_info&0xf) == STT_TLS)
+ return __tls_get_addr((tls_mod_off_t []){def.dso->tls_id, def.sym->st_value-DTP_OFFSET});
+ if (DL_FDPIC && (def.sym->st_info&0xf) == STT_FUNC)
+ return def.dso->funcdescs + (def.sym - def.dso->syms);
+ return laddr(def.dso, def.sym->st_value);
+}
+
+int dladdr(const void *addr_arg, Dl_info *info)
+{
+ size_t addr = (size_t)addr_arg;
+ struct dso *p;
+ Sym *sym, *bestsym;
+ uint32_t nsym;
+ char *strings;
+ size_t best = 0;
+ size_t besterr = -1;
+
+ pthread_rwlock_rdlock(&lock);
+ p = addr2dso(addr);
+ pthread_rwlock_unlock(&lock);
+
+ if (!p) return 0;
+
+ sym = p->syms;
+ strings = p->strings;
+ nsym = count_syms(p);
+
+ if (DL_FDPIC) {
+ size_t idx = (addr-(size_t)p->funcdescs)
+ / sizeof(*p->funcdescs);
+ if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) {
+ best = (size_t)(p->funcdescs + idx);
+ bestsym = sym + idx;
+ besterr = 0;
+ }
+ }
+
+ if (!best) for (; nsym; nsym--, sym++) {
+ if (sym->st_value
+ && (1<<(sym->st_info&0xf) & OK_TYPES)
+ && (1<<(sym->st_info>>4) & OK_BINDS)) {
+ size_t symaddr = (size_t)laddr(p, sym->st_value);
+ if (symaddr > addr || symaddr <= best)
+ continue;
+ best = symaddr;
+ bestsym = sym;
+ besterr = addr - symaddr;
+ if (addr == symaddr)
+ break;
+ }
+ }
+
+ if (best && besterr > bestsym->st_size-1) {
+ best = 0;
+ bestsym = 0;
+ }
+
+ info->dli_fname = p->name;
+ info->dli_fbase = p->map;
+
+ if (!best) {
+ info->dli_sname = 0;
+ info->dli_saddr = 0;
+ return 1;
+ }
+
+ if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC)
+ best = (size_t)(p->funcdescs + (bestsym - p->syms));
+ info->dli_sname = strings + bestsym->st_name;
+ info->dli_saddr = (void *)best;
+
+ return 1;
+}
+
+hidden void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
+{
+ void *res;
+ pthread_rwlock_rdlock(&lock);
+ res = do_dlsym(p, s, ra);
+ pthread_rwlock_unlock(&lock);
+ return res;
+}
+
+hidden void *__dlsym_redir_time64(void *restrict p, const char *restrict s, void *restrict ra)
+{
+#if _REDIR_TIME64
+ const char *suffix, *suffix2 = "";
+ char redir[36];
+
+ /* Map the symbol name to a time64 version of itself according to the
+ * pattern used for naming the redirected time64 symbols. */
+ size_t l = strnlen(s, sizeof redir);
+ if (l<4 || l==sizeof redir) goto no_redir;
+ if (s[l-2]=='_' && s[l-1]=='r') {
+ l -= 2;
+ suffix2 = s+l;
+ }
+ if (l<4) goto no_redir;
+ if (!strcmp(s+l-4, "time")) suffix = "64";
+ else suffix = "_time64";
+
+ /* Use the presence of the remapped symbol name in libc to determine
+ * whether it's one that requires time64 redirection; replace if so. */
+ snprintf(redir, sizeof redir, "__%.*s%s%s", (int)l, s, suffix, suffix2);
+ if (find_sym(&ldso, redir, 1).sym) s = redir;
+no_redir:
+#endif
+ return __dlsym(p, s, ra);
+}
+
+int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void *data), void *data)
+{
+ struct dso *current;
+ struct dl_phdr_info info;
+ int ret = 0;
+ for(current = head; current;) {
+ info.dlpi_addr = (uintptr_t)current->base;
+ info.dlpi_name = current->name;
+ info.dlpi_phdr = current->phdr;
+ info.dlpi_phnum = current->phnum;
+ info.dlpi_adds = gencnt;
+ info.dlpi_subs = 0;
+ info.dlpi_tls_modid = current->tls_id;
+ info.dlpi_tls_data = !current->tls_id ? 0 :
+ __tls_get_addr((tls_mod_off_t[]){current->tls_id,0});
+
+ ret = (callback)(&info, sizeof (info), data);
+
+ if (ret != 0) break;
+
+ pthread_rwlock_rdlock(&lock);
+ current = current->next;
+ pthread_rwlock_unlock(&lock);
+ }
+ return ret;
+}
+
+static void error(const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ if (!runtime) {
+ vdprintf(2, fmt, ap);
+ dprintf(2, "\n");
+ ldso_fail = 1;
+ va_end(ap);
+ return;
+ }
+ __dl_vseterr(fmt, ap);
+ va_end(ap);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-10-18 04:52:48 +0000