#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 <stdint.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <errno.h>
-#include <limits.h>
-#include <elf.h>
#include <link.h>
#include <setjmp.h>
#include <pthread.h>
#include <dlfcn.h>
#include "pthread_impl.h"
#include "libc.h"
+#include "dynlink.h"
-static int errflag;
-static char errbuf[128];
+static void error(const char *, ...);
#ifdef SHARED
-#if ULONG_MAX == 0xffffffff
-typedef Elf32_Ehdr Ehdr;
-typedef Elf32_Phdr Phdr;
-typedef Elf32_Sym Sym;
-#define R_TYPE(x) ((x)&255)
-#define R_SYM(x) ((x)>>8)
-#else
-typedef Elf64_Ehdr Ehdr;
-typedef Elf64_Phdr Phdr;
-typedef Elf64_Sym Sym;
-#define R_TYPE(x) ((x)&0xffffffff)
-#define R_SYM(x) ((x)>>32)
-#endif
-
#define MAXP2(a,b) (-(-(a)&-(b)))
#define ALIGN(x,y) ((x)+(y)-1 & -(y))
void *base;
};
+struct td_index {
+ size_t args[2];
+ struct td_index *next;
+};
+
struct dso {
unsigned char *base;
char *name;
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;
signed char global;
char relocated;
char constructed;
- struct dso **deps;
+ char kernel_mapped;
+ struct dso **deps, *needed_by;
+ char *rpath_orig, *rpath;
void *tls_image;
size_t tls_len, tls_size, tls_align, tls_id, tls_offset;
+ size_t relro_start, relro_end;
void **new_dtv;
unsigned char *new_tls;
- int new_dtv_idx, new_tls_idx;
+ volatile int new_dtv_idx, new_tls_idx;
+ struct td_index *td_index;
struct dso *fini_next;
char *shortname;
char buf[];
struct dso *dso;
};
-#include "reloc.h"
-
-void __init_ssp(size_t *);
-void *__install_initial_tls(void *);
+int __init_tp(void *);
void __init_libc(char **, char *);
-static struct dso *head, *tail, *ldso, *fini_head;
-static char *env_path, *sys_path, *r_path;
+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 ssp_used;
static int runtime;
static int ldd_mode;
static int ldso_fail;
static jmp_buf *rtld_fail;
static pthread_rwlock_t lock;
static struct debug debug;
-static size_t tls_cnt, tls_offset, tls_align = 4*sizeof(size_t);
+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 };
struct debug *_dl_debug_addr = &debug;
-#define AUX_CNT 38
-#define DYN_CNT 34
+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)
static void decode_vec(size_t *v, size_t *a, size_t cnt)
{
- memset(a, 0, cnt*sizeof(size_t));
- for (; v[0]; v+=2) if (v[0]<cnt) {
- a[0] |= 1ULL<<v[0];
+ 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];
}
}
uint32_t *hashtab = dso->hashtab;
char *strings = dso->strings;
for (i=hashtab[2+h%hashtab[0]]; i; i=hashtab[2+hashtab[0]+i]) {
- if (!strcmp(s, strings+syms[i].st_name))
+ if ((!dso->versym || dso->versym[i] >= 0)
+ && (!strcmp(s, strings+syms[i].st_name)))
return syms+i;
}
return 0;
static Sym *gnu_lookup(const char *s, uint32_t h1, struct dso *dso)
{
- Sym *sym;
- char *strings;
+ Sym *syms = dso->syms;
+ char *strings = dso->strings;
uint32_t *hashtab = dso->ghashtab;
uint32_t nbuckets = hashtab[0];
uint32_t *buckets = hashtab + 4 + hashtab[2]*(sizeof(size_t)/4);
uint32_t h2;
uint32_t *hashval;
- uint32_t n = buckets[h1 % nbuckets];
+ uint32_t i = buckets[h1 % nbuckets];
- if (!n) return 0;
+ if (!i) return 0;
- strings = dso->strings;
- sym = dso->syms + n;
- hashval = buckets + nbuckets + (n - hashtab[1]);
+ hashval = buckets + nbuckets + (i - hashtab[1]);
- for (h1 |= 1; ; sym++) {
+ for (h1 |= 1; ; i++) {
h2 = *hashval++;
- if ((h1 == (h2|1)) && !strcmp(s, strings + sym->st_name))
- return sym;
+ if ((!dso->versym || dso->versym[i] >= 0)
+ && (h1 == (h2|1)) && !strcmp(s, strings + syms[i].st_name))
+ return syms+i;
if (h2 & 1) break;
}
#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 = 0;
struct symdef def = {0};
- if (dso->ghashtab) {
- gh = gnu_hash(s);
- if (gh == 0x1f4039c9 && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
- } else {
- h = sysv_hash(s);
- if (h == 0x595a4cc && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
- }
for (; dso; dso=dso->next) {
Sym *sym;
if (!dso->global) continue;
}
if (!sym) continue;
if (!sym->st_shndx)
- if (need_def || (sym->st_info&0xf) == STT_TLS)
+ 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)
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;
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])) continue;
type = R_TYPE(rel[1]);
+ if (type == REL_NONE) continue;
sym_index = R_SYM(rel[1]);
+ reloc_addr = (void *)(base + rel[0]);
if (sym_index) {
sym = syms + sym_index;
name = strings + sym->st_name;
- ctx = IS_COPY(type) ? head->next : head;
- def = find_sym(ctx, name, IS_PLT(type));
- if (!def.sym && sym->st_info>>4 != STB_WEAK) {
- snprintf(errbuf, sizeof errbuf,
- "Error relocating %s: %s: symbol not found",
+ ctx = type==REL_COPY ? head->next : head;
+ def = 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);
- dprintf(2, "%s\n", errbuf);
- ldso_fail = 1;
continue;
}
} else {
sym = 0;
def.sym = 0;
- def.dso = 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)def.dso->base+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_DTPMOD:
+ *reloc_addr = def.dso->tls_id;
+ break;
+ case REL_DTPOFF:
+ *reloc_addr = tls_val + addend;
+ 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;
}
- do_single_reloc(dso, base, (void *)(base + rel[0]), type,
- stride>2 ? rel[2] : 0, sym, sym?sym->st_size:0, def,
- def.sym?(size_t)(def.dso->base+def.sym->st_value):0);
}
}
* and "donate" them to the heap by setting up minimal malloc
* structures and then freeing them. */
-static void reclaim(unsigned char *base, size_t start, size_t end)
+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 = (size_t *)(base + start);
- z = (size_t *)(base + end);
+ a = (size_t *)(dso->base + start);
+ z = (size_t *)(dso->base + end);
a[-2] = 1;
a[-1] = z[0] = end-start + 2*sizeof(size_t) | 1;
z[1] = 1;
free(a);
}
-static void reclaim_gaps(unsigned char *base, Phdr *ph, size_t phent, size_t phcnt)
+static void reclaim_gaps(struct dso *dso)
{
- for (; phcnt--; ph=(void *)((char *)ph+phent)) {
+ 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(base, ph->p_vaddr & -PAGE_SIZE, ph->p_vaddr);
- reclaim(base, ph->p_vaddr+ph->p_memsz,
+ 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 *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;
Ehdr *eh;
Phdr *ph, *ph0;
unsigned prot;
- unsigned char *map, *base;
- size_t dyn;
+ 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);
- if (l<(int)sizeof *eh) return 0;
eh = buf;
- if (eh->e_type != ET_DYN && eh->e_type != ET_EXEC) {
- errno = ENOEXEC;
- return 0;
- }
+ 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 *eh > l) return 0;
- if (eh->e_phoff + phsize > l) {
+ 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 != phsize) return 0;
+ 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)
+ if (ph->p_type == PT_DYNAMIC) {
dyn = ph->p_vaddr;
- if (ph->p_type == PT_TLS) {
+ } 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;
if (ph->p_vaddr < addr_min) {
addr_max = ph->p_vaddr+ph->p_memsz;
}
}
- if (!dyn) return 0;
+ if (!dyn) goto noexec;
addr_max += PAGE_SIZE-1;
addr_max &= -PAGE_SIZE;
addr_min &= -PAGE_SIZE;
* use the invalid part; we just need to reserve the right
* amount of virtual address space to map over later. */
map = mmap((void *)addr_min, map_len, prot, MAP_PRIVATE, fd, off_start);
- if (map==MAP_FAILED) return 0;
+ if (map==MAP_FAILED) goto error;
/* 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) {
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) continue;
goto error;
break;
}
- if (!runtime) reclaim_gaps(base, ph0, eh->e_phentsize, eh->e_phnum);
dso->map = map;
dso->map_len = map_len;
dso->base = base;
dso->dynv = (void *)(base+dyn);
if (dso->tls_size) dso->tls_image = (void *)(base+tls_image);
+ if (!runtime) reclaim_gaps(dso);
+ free(allocated_buf);
return map;
+noexec:
+ errno = ENOEXEC;
error:
- munmap(map, map_len);
+ if (map!=MAP_FAILED) munmap(map, map_len);
+ free(allocated_buf);
return 0;
}
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)
- continue;
- if ((fd = open(buf, O_RDONLY|O_CLOEXEC))>=0) return fd;
+ 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] = {0};
+ size_t dyn[DYN_CNT];
decode_vec(p->dynv, dyn, DYN_CNT);
p->syms = (void *)(p->base + dyn[DT_SYMTAB]);
p->strings = (void *)(p->base + dyn[DT_STRTAB]);
if (dyn[0]&(1<<DT_HASH))
p->hashtab = (void *)(p->base + dyn[DT_HASH]);
+ if (dyn[0]&(1<<DT_RPATH))
+ p->rpath_orig = (void *)(p->strings + dyn[DT_RPATH]);
+ if (dyn[0]&(1<<DT_RUNPATH))
+ p->rpath_orig = (void *)(p->strings + dyn[DT_RUNPATH]);
if (search_vec(p->dynv, dyn, DT_GNU_HASH))
p->ghashtab = (void *)(p->base + *dyn);
+ if (search_vec(p->dynv, dyn, DT_VERSYM))
+ p->versym = (void *)(p->base + *dyn);
}
-static struct dso *load_library(const char *name)
+static struct dso *load_library(const char *name, struct dso *needed_by)
{
char buf[2*NAME_MAX+2];
const char *pathname;
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[] =
char *z = strchr(name, '.');
if (z) {
size_t l = z-name;
- for (rp=reserved; *rp && memcmp(name+3, rp, l-3); rp+=strlen(rp)+1);
+ 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
if (!(reported & mask)) {
reported |= mask;
dprintf(1, "\t%s => %s (%p)\n",
- name, ldso->name,
- ldso->base);
+ name, ldso.name,
+ ldso.base);
}
}
is_self = 1;
}
}
}
- if (!strcmp(name, ldso->name)) 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;
+ if (!ldso.prev) {
+ tail->next = &ldso;
+ ldso.prev = tail;
+ tail = ldso.next ? ldso.next : &ldso;
}
- return ldso;
+ return &ldso;
}
if (strchr(name, '/')) {
pathname = name;
}
if (strlen(name) > NAME_MAX) return 0;
fd = -1;
- if (r_path) fd = path_open(name, r_path, buf, sizeof buf);
- if (fd < 0 && env_path) fd = path_open(name, env_path, buf, sizeof buf);
- if (fd < 0) {
+ 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]=='/') {
+ if (ldso.name[0]=='/') {
char *s, *t, *z;
- for (s=t=z=ldso->name; *s; s++)
+ for (s=t=z=ldso.name; *s; s++)
if (*s=='/') z=t, t=s;
- prefix_len = z-ldso->name;
+ prefix_len = z-ldso.name;
if (prefix_len < PATH_MAX)
- prefix = ldso->name;
+ prefix = ldso.name;
}
if (!prefix) {
prefix = "";
sys_path = "";
}
fclose(f);
+ } else if (errno != ENOENT) {
+ sys_path = "";
}
}
if (!sys_path) sys_path = "/lib:/usr/local/lib:/usr/lib";
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) {
- if (runtime && !__pthread_self_init()) {
- munmap(map, p->map_len);
- free(p);
- return 0;
- }
p->tls_id = ++tls_cnt;
tls_align = MAXP2(tls_align, p->tls_align);
#ifdef TLS_ABOVE_TP
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_RPATH) continue;
- r_path = (void *)(p->strings + p->dynv[i+1]);
- }
for (i=0; p->dynv[i]; i+=2) {
if (p->dynv[i] != DT_NEEDED) continue;
- dep = load_library(p->strings + p->dynv[i+1]);
+ dep = load_library(p->strings + p->dynv[i+1], p);
if (!dep) {
- snprintf(errbuf, sizeof errbuf,
- "Error loading shared library %s: %m (needed by %s)",
+ error("Error loading shared library %s: %m (needed by %s)",
p->strings + p->dynv[i+1], p->name);
if (runtime) longjmp(*rtld_fail, 1);
- dprintf(2, "%s\n", errbuf);
- ldso_fail = 1;
continue;
}
if (runtime) {
*deps = tmp;
}
}
- r_path = 0;
}
}
int tmp;
char *z;
for (z=s; *z; s=z) {
- for ( ; *s && isspace(*s); s++);
- for (z=s; *z && !isspace(*z); z++);
+ for ( ; *s && (isspace(*s) || *s==':'); s++);
+ for (z=s; *z && !isspace(*z) && *z!=':'; z++);
tmp = *z;
*z = 0;
- load_library(s);
+ load_library(s, 0);
*z = tmp;
}
}
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] = {0};
+ size_t dyn[DYN_CNT];
for (; p; p=p->next) {
if (p->relocated) continue;
decode_vec(p->dynv, dyn, DYN_CNT);
-#ifdef NEED_ARCH_RELOCS
- do_arch_relocs(p, head);
-#endif
+ if (NEED_MIPS_GOT_RELOCS)
+ do_mips_relocs(p, (void *)(p->base+dyn[DT_PLTGOT]));
do_relocs(p, (void *)(p->base+dyn[DT_JMPREL]), dyn[DT_PLTRELSZ],
2+(dyn[DT_PLTREL]==DT_RELA));
do_relocs(p, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ], 2);
do_relocs(p, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ], 3);
+
+ if (head != &ldso && p->relro_start != p->relro_end &&
+ mprotect(p->base+p->relro_start, p->relro_end-p->relro_start, PROT_READ) < 0) {
+ error("Error relocating %s: RELRO protection failed: %m",
+ p->name);
+ if (runtime) longjmp(*rtld_fail, 1);
+ }
+
p->relocated = 1;
}
}
-static size_t find_dyn(Phdr *ph, size_t cnt, size_t stride)
-{
- for (; cnt--; ph = (void *)((char *)ph + stride))
- if (ph->p_type == PT_DYNAMIC)
- return ph->p_vaddr;
- return 0;
-}
-
-static void find_map_range(Phdr *ph, size_t cnt, size_t stride, struct dso *p)
+static void kernel_mapped_dso(struct dso *p)
{
- size_t min_addr = -1, max_addr = 0;
- for (; cnt--; ph = (void *)((char *)ph + stride)) {
+ 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 = (void *)(p->base + 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;
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;
}
static void do_fini()
{
struct dso *p;
- size_t dyn[DYN_CNT] = {0};
+ 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);
static void do_init_fini(struct dso *p)
{
- size_t dyn[DYN_CNT] = {0};
+ 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
if (need_locking) pthread_mutex_unlock(&init_fini_lock);
}
-void _dl_debug_state(void)
+static void dl_debug_state(void)
+{
+}
+
+weak_alias(dl_debug_state, _dl_debug_state);
+
+void __reset_tls()
{
+ pthread_t self = __pthread_self();
+ struct dso *p;
+ for (p=head; p; p=p->next) {
+ if (!p->tls_id || !self->dtv[p->tls_id]) continue;
+ memcpy(self->dtv[p->tls_id], p->tls_image, p->tls_len);
+ memset((char *)self->dtv[p->tls_id]+p->tls_len, 0,
+ p->tls_size - p->tls_len);
+ if (p->tls_id == (size_t)self->dtv[0]) break;
+ }
}
void *__copy_tls(unsigned char *mem)
{
pthread_t td;
struct dso *p;
-
- if (!tls_cnt) return mem;
-
- void **dtv = (void *)mem;
- dtv[0] = (void *)tls_cnt;
+ void **dtv;
#ifdef TLS_ABOVE_TP
- mem += sizeof(void *) * (tls_cnt+1);
+ dtv = (void **)(mem + libc.tls_size) - (tls_cnt + 1);
+
mem += -((uintptr_t)mem + sizeof(struct pthread)) & (tls_align-1);
td = (pthread_t)mem;
mem += sizeof(struct pthread);
memcpy(dtv[p->tls_id], p->tls_image, p->tls_len);
}
#else
+ dtv = (void **)mem;
+
mem += libc.tls_size - sizeof(struct pthread);
mem -= (uintptr_t)mem & (tls_align-1);
td = (pthread_t)mem;
memcpy(dtv[p->tls_id], p->tls_image, p->tls_len);
}
#endif
- td->dtv = dtv;
+ dtv[0] = (void *)tls_cnt;
+ td->dtv = td->dtv_copy = dtv;
return td;
}
-void *__tls_get_addr(size_t *v)
+__attribute__((__visibility__("hidden")))
+void *__tls_get_new(size_t *v)
{
pthread_t self = __pthread_self();
- if (v[0]<=(size_t)self->dtv[0] && self->dtv[v[0]])
- return (char *)self->dtv[v[0]]+v[1];
/* Block signals to make accessing new TLS async-signal-safe */
sigset_t set;
- pthread_sigmask(SIG_BLOCK, SIGALL_SET, &set);
- if (v[0]<=(size_t)self->dtv[0] && self->dtv[v[0]]) {
- pthread_sigmask(SIG_SETMASK, &set, 0);
+ __block_all_sigs(&set);
+ if (v[0]<=(size_t)self->dtv[0]) {
+ __restore_sigs(&set);
return (char *)self->dtv[v[0]]+v[1];
}
memcpy(newdtv, self->dtv,
((size_t)self->dtv[0]+1) * sizeof(void *));
newdtv[0] = (void *)v[0];
- self->dtv = newdtv;
+ self->dtv = self->dtv_copy = newdtv;
}
- /* Get new TLS memory from new DSO */
- unsigned char *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[v[0]] = mem;
- memcpy(mem, p->tls_image, p->tls_len);
- pthread_sigmask(SIG_SETMASK, &set, 0);
+ /* 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];
}
tls_align);
}
-void *__dynlink(int argc, char **argv)
+/* 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. */
+
+void __dls2(unsigned char *base, size_t *sp)
+{
+ Ehdr *ehdr = (void *)base;
+ ldso.base = base;
+ ldso.name = ldso.shortname = "libc.so";
+ ldso.global = 1;
+ ldso.phnum = ehdr->e_phnum;
+ ldso.phdr = (void *)(base + ehdr->e_phoff);
+ ldso.phentsize = ehdr->e_phentsize;
+ kernel_mapped_dso(&ldso);
+ decode_dyn(&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 = (void *)(base+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])) 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);
+ ((stage3_func)(ldso.base+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)
{
- size_t aux[AUX_CNT] = {0};
+ static struct dso app, vdso;
+ size_t aux[AUX_CNT], *auxv;
size_t i;
- Phdr *phdr;
- Ehdr *ehdr;
- static struct dso builtin_dsos[3];
- struct dso *const app = builtin_dsos+0;
- struct dso *const lib = builtin_dsos+1;
- struct dso *const vdso = builtin_dsos+2;
char *env_preload=0;
size_t vdso_base;
- size_t *auxv;
+ int argc = *sp;
+ char **argv = (void *)(sp+1);
+ char **argv_orig = argv;
char **envp = argv+argc+1;
- /* Find aux vector just past environ[] */
- for (i=argc+1; argv[i]; i++)
- if (!memcmp(argv[i], "LD_LIBRARY_PATH=", 16))
- env_path = argv[i]+16;
- else if (!memcmp(argv[i], "LD_PRELOAD=", 11))
- env_preload = argv[i]+11;
- auxv = (void *)(argv+i+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);
-
- /* Only trust user/env if kernel says we're not suid/sgid */
- if ((aux[0]&0x7800)!=0x7800 || aux[AT_UID]!=aux[AT_EUID]
- || aux[AT_GID]!=aux[AT_EGID] || aux[AT_SECURE]) {
- env_path = 0;
- env_preload = 0;
+ __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;
+ if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
+ a_crash();
}
- /* If the dynamic linker was invoked as a program itself, AT_BASE
- * will not be set. In that case, we assume the base address is
- * the start of the page containing the PHDRs; I don't know any
- * better approach... */
- if (!aux[AT_BASE]) {
- aux[AT_BASE] = aux[AT_PHDR] & -PAGE_SIZE;
- aux[AT_PHDR] = aux[AT_PHENT] = aux[AT_PHNUM] = 0;
+ /* 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");
}
- /* The dynamic linker load address is passed by the kernel
- * in the AUX vector, so this is easy. */
- lib->base = (void *)aux[AT_BASE];
- lib->name = lib->shortname = "libc.so";
- lib->global = 1;
- ehdr = (void *)lib->base;
- lib->phnum = ehdr->e_phnum;
- lib->phdr = (void *)(aux[AT_BASE]+ehdr->e_phoff);
- find_map_range(lib->phdr, ehdr->e_phnum, ehdr->e_phentsize, lib);
- lib->dynv = (void *)(lib->base + find_dyn(lib->phdr,
- ehdr->e_phnum, ehdr->e_phentsize));
- decode_dyn(lib);
-
- if (aux[AT_PHDR]) {
+ /* 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. */
- app->phdr = phdr = (void *)aux[AT_PHDR];
- app->phnum = aux[AT_PHNUM];
+ 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);
+ 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;
+ app.tls_len = phdr->p_filesz;
+ app.tls_size = phdr->p_memsz;
+ app.tls_align = phdr->p_align;
}
}
- if (app->tls_size) app->tls_image = (char *)app->base + tls_image;
- if (interp_off) lib->name = (char *)app->base + interp_off;
- app->name = argv[0];
- app->dynv = (void *)(app->base + find_dyn(
- (void *)aux[AT_PHDR], aux[AT_PHNUM], aux[AT_PHENT]));
- find_map_range((void *)aux[AT_PHDR],
- aux[AT_PHNUM], aux[AT_PHENT], app);
+ if (app.tls_size) app.tls_image = (char *)app.base + tls_image;
+ if (interp_off) ldso.name = (char *)app.base + 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++ = (void *)-1;
- if (argv[0] && !strcmp(argv[0], "--")) *argv++ = (void *)-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/dynamic program loader\n");
- dprintf(2, "usage: %s pathname%s\n", ldname,
+ dprintf(2, "musl libc\n"
+ "Version %s\n"
+ "Dynamic Program Loader\n"
+ "Usage: %s [options] [--] pathname%s\n",
+ __libc_get_version(), ldname,
ldd_mode ? "" : " [args]");
_exit(1);
}
_exit(1);
}
runtime = 1;
- ehdr = (void *)map_library(fd, app);
+ 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);
- lib->name = ldname;
- app->name = argv[0];
- aux[AT_ENTRY] = (size_t)app->base + ehdr->e_entry;
+ ldso.name = ldname;
+ app.name = argv[0];
+ aux[AT_ENTRY] = (size_t)app.base + 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)
- lib->name = (void *)(app->base
- + app->phdr[i].p_vaddr);
+ for (i=0; i<app.phnum; i++) {
+ if (app.phdr[i].p_type == PT_INTERP)
+ ldso.name = (void *)(app.base
+ + app.phdr[i].p_vaddr);
}
- dprintf(1, "\t%s (%p)\n", lib->name, lib->base);
+ dprintf(1, "\t%s (%p)\n", ldso.name, ldso.base);
}
}
- if (app->tls_size) {
- app->tls_id = tls_cnt = 1;
+ if (app.tls_size) {
+ 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) );
+ 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) );
+ 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);
+ tls_align = MAXP2(tls_align, app.tls_align);
}
- app->global = 1;
- decode_dyn(app);
+ app.global = 1;
+ decode_dyn(&app);
/* Attach to vdso, if provided by the kernel */
if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) {
- ehdr = (void *)vdso_base;
- vdso->phdr = phdr = (void *)(vdso_base + ehdr->e_phoff);
- vdso->phnum = ehdr->e_phnum;
+ 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);
+ 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.base = (void *)(vdso_base - phdr->p_vaddr + phdr->p_offset);
}
- vdso->name = "";
- vdso->shortname = "linux-gate.so.1";
- vdso->global = 1;
- decode_dyn(vdso);
- vdso->prev = lib;
- lib->next = vdso;
+ 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. We temporarily
- * append the dynamic linker/libc so we can relocate it, then
- * restore the initial chain in preparation for loading third
- * party libraries (preload/needed). */
- head = tail = app;
- ldso = lib;
- app->next = lib;
- reloc_all(lib);
- app->next = 0;
-
- /* PAST THIS POINT, ALL LIBC INTERFACES ARE FULLY USABLE. */
+ /* Initial dso chain consists only of the app. */
+ head = tail = &app;
/* Donate unused parts of app and library mapping to malloc */
- reclaim_gaps(app->base, (void *)aux[AT_PHDR], aux[AT_PHENT], aux[AT_PHNUM]);
- ehdr = (void *)lib->base;
- reclaim_gaps(lib->base, (void *)(lib->base+ehdr->e_phoff),
- ehdr->e_phentsize, ehdr->e_phnum);
+ reclaim_gaps(&app);
+ reclaim_gaps(&ldso);
/* Load preload/needed libraries, add their symbols to the global
- * namespace, and perform all remaining relocations. The main
- * program must be relocated LAST since it may contain copy
- * relocations which depend on libraries' relocations. */
+ * namespace, and perform all remaining relocations. */
if (env_preload) load_preload(env_preload);
- load_deps(app);
- make_global(app);
+ 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
- reloc_all(app->next);
- reloc_all(app);
+ /* 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 (tls_cnt) {
- void *mem = mmap(0, libc.tls_size, PROT_READ|PROT_WRITE,
- MAP_ANONYMOUS|MAP_PRIVATE, -1, 0);
- if (mem==MAP_FAILED ||
- !__install_initial_tls(__copy_tls(mem))) {
+ 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. If the dynamic loader (dlopen) will not be used, free
- * all memory used by the dynamic linker. */
+ * error. */
runtime = 1;
-#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
debug.ver = 1;
- debug.bp = _dl_debug_state;
+ debug.bp = dl_debug_state;
debug.head = head;
- debug.base = lib->base;
+ debug.base = ldso.base;
debug.state = 0;
_dl_debug_state();
- if (ssp_used) __init_ssp((void *)aux[AT_RANDOM]);
__init_libc(envp, argv[0]);
atexit(do_fini);
errno = 0;
do_init_fini(tail);
- return (void *)aux[AT_ENTRY];
+ CRTJMP((void *)aux[AT_ENTRY], argv-1);
+ for(;;);
}
void *dlopen(const char *file, int mode)
for (p=orig_tail->next; p; p=next) {
next = p->next;
munmap(p->map, p->map_len);
+ while (p->td_index) {
+ void *tmp = p->td_index->next;
+ free(p->td_index);
+ p->td_index = tmp;
+ }
+ if (p->rpath != p->rpath_orig)
+ free(p->rpath);
free(p->deps);
free(p);
}
tail = orig_tail;
tail->next = 0;
p = 0;
- errflag = 1;
goto end;
- } else p = load_library(file);
+ } else p = load_library(file, head);
if (!p) {
- snprintf(errbuf, sizeof errbuf, noload ?
+ error(noload ?
"Library %s is not already loaded" :
"Error loading shared library %s: %m",
file);
- errflag = 1;
goto end;
}
}
update_tls_size();
-
- if (ssp_used) __init_ssp(libc.auxv);
-
_dl_debug_state();
orig_tail = tail;
end:
{
struct dso *p;
for (p=head; p; p=p->next) if (h==p) return 0;
- snprintf(errbuf, sizeof errbuf, "Invalid library handle %p", (void *)h);
- errflag = 1;
+ error("Invalid library handle %p", (void *)h);
return 1;
}
+void *__tls_get_addr(size_t *);
+
static void *do_dlsym(struct dso *p, const char *s, void *ra)
{
size_t i;
return __tls_get_addr((size_t []){def.dso->tls_id, def.sym->st_value});
return def.dso->base + def.sym->st_value;
}
- if (p != RTLD_DEFAULT && p != RTLD_NEXT && invalid_dso_handle(p))
+ if (invalid_dso_handle(p))
return 0;
if (p->ghashtab) {
gh = gnu_hash(s);
return p->deps[i]->base + sym->st_value;
}
failed:
- errflag = 1;
- snprintf(errbuf, sizeof errbuf, "Symbol not found: %s", s);
+ error("Symbol not found: %s", s);
return 0;
}
-int __dladdr(void *addr, Dl_info *info)
+int __dladdr(const void *addr, Dl_info *info)
{
struct dso *p;
Sym *sym;
uint32_t *hashval;
buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4);
sym += p->ghashtab[1];
- for (i = 0; i < p->ghashtab[0]; i++) {
+ for (i = nsym = 0; i < p->ghashtab[0]; i++) {
if (buckets[i] > nsym)
nsym = buckets[i];
}
return 1;
}
+__attribute__((__visibility__("hidden")))
void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
{
void *res;
#else
static int invalid_dso_handle(void *h)
{
- snprintf(errbuf, sizeof errbuf, "Invalid library handle %p", (void *)h);
- errflag = 1;
+ error("Invalid library handle %p", (void *)h);
return 1;
}
void *dlopen(const char *file, int mode)
{
+ error("Dynamic loading not supported");
return 0;
}
void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra)
{
+ error("Symbol not found: %s", s);
return 0;
}
-int __dladdr (void *addr, Dl_info *info)
+int __dladdr (const void *addr, Dl_info *info)
{
return 0;
}
{
if (invalid_dso_handle(dso)) return -1;
if (req != RTLD_DI_LINKMAP) {
- snprintf(errbuf, sizeof errbuf, "Unsupported request %d", req);
- errflag = 1;
+ error("Unsupported request %d", req);
return -1;
}
*(struct link_map **)res = dso;
char *dlerror()
{
- if (!errflag) return 0;
- errflag = 0;
- return errbuf;
+ pthread_t self = __pthread_self();
+ if (!self->dlerror_flag) return 0;
+ self->dlerror_flag = 0;
+ char *s = self->dlerror_buf;
+ if (s == (void *)-1)
+ return "Dynamic linker failed to allocate memory for error message";
+ else
+ return s;
}
int dlclose(void *p)
{
return invalid_dso_handle(p);
}
+
+void __dl_thread_cleanup(void)
+{
+ pthread_t self = __pthread_self();
+ if (self->dlerror_buf != (void *)-1)
+ free(self->dlerror_buf);
+}
+
+static void error(const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+#ifdef SHARED
+ if (!runtime) {
+ vdprintf(2, fmt, ap);
+ dprintf(2, "\n");
+ ldso_fail = 1;
+ va_end(ap);
+ return;
+ }
+#endif
+ pthread_t self = __pthread_self();
+ if (self->dlerror_buf != (void *)-1)
+ free(self->dlerror_buf);
+ size_t len = vsnprintf(0, 0, fmt, ap);
+ va_end(ap);
+ char *buf = malloc(len+1);
+ if (buf) {
+ va_start(ap, fmt);
+ vsnprintf(buf, len+1, fmt, ap);
+ va_end(ap);
+ } else {
+ buf = (void *)-1;
+ }
+ self->dlerror_buf = buf;
+ self->dlerror_flag = 1;
+}
projects / musl / blobdiff