#include <pthread.h>
#include <ctype.h>
#include <dlfcn.h>
+#include "pthread_impl.h"
+#include "libc.h"
+#undef libc
static int errflag;
static char errbuf[128];
char relocated;
char constructed;
struct dso **deps;
+ void *tls_image;
+ size_t tls_len, tls_size, tls_align, tls_id, tls_offset;
char *shortname;
char buf[];
};
+struct symdef {
+ Sym *sym;
+ struct dso *dso;
+};
+
#include "reloc.h"
void __init_ssp(size_t *);
+void *__install_initial_tls(void *);
static struct dso *head, *tail, *libc;
static char *env_path, *sys_path, *r_path;
-static int rtld_used;
static int ssp_used;
static int runtime;
static int ldd_mode;
static pthread_rwlock_t lock;
static struct debug debug;
static size_t *auxv;
+static size_t tls_cnt, tls_size;
struct debug *_dl_debug_addr = &debug;
return 0;
}
-#define OK_TYPES (1<<STT_NOTYPE | 1<<STT_OBJECT | 1<<STT_FUNC | 1<<STT_COMMON)
+#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)
-static void *find_sym(struct dso *dso, const char *s, int need_def)
+static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
{
uint32_t h = 0, gh = 0;
- void *def = 0;
+ struct symdef def = {0};
if (dso->ghashtab) {
gh = gnu_hash(s);
- if (gh == 0xf9040207 && !strcmp(s, "dlopen")) rtld_used = 1;
- if (gh == 0xf4dc4ae && !strcmp(s, "dlsym")) rtld_used = 1;
if (gh == 0x1f4039c9 && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
} else {
h = sysv_hash(s);
- if (h == 0x6b366be && !strcmp(s, "dlopen")) rtld_used = 1;
- if (h == 0x6b3afd && !strcmp(s, "dlsym")) rtld_used = 1;
if (h == 0x595a4cc && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
}
for (; dso; dso=dso->next) {
if (sym && (!need_def || sym->st_shndx) && sym->st_value
&& (1<<(sym->st_info&0xf) & OK_TYPES)
&& (1<<(sym->st_info>>4) & OK_BINDS)) {
- if (def && sym->st_info>>4 == STB_WEAK) continue;
- def = dso->base + sym->st_value;
+ if (def.sym && sym->st_info>>4 == STB_WEAK) continue;
+ def.sym = sym;
+ def.dso = dso;
if (sym->st_info>>4 == STB_GLOBAL) break;
}
}
char *strings = dso->strings;
Sym *sym;
const char *name;
- size_t sym_val, sym_size;
- size_t *reloc_addr;
void *ctx;
int type;
int sym_index;
+ struct symdef def;
for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) {
- reloc_addr = (void *)(base + rel[0]);
type = R_TYPE(rel[1]);
sym_index = R_SYM(rel[1]);
if (sym_index) {
sym = syms + sym_index;
name = strings + sym->st_name;
ctx = IS_COPY(type) ? head->next : head;
- sym_val = (size_t)find_sym(ctx, name, IS_PLT(type));
- if (!sym_val && sym->st_info>>4 != STB_WEAK) {
+ 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",
dso->name, name);
ldso_fail = 1;
continue;
}
- sym_size = sym->st_size;
} else {
- sym_val = sym_size = 0;
+ sym = 0;
+ def.sym = 0;
+ def.dso = 0;
}
- do_single_reloc(reloc_addr, type, sym_val, sym_size, base, rel[2]);
+ 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);
}
}
}
}
-static void *map_library(int fd, size_t *lenp, unsigned char **basep, size_t *dynp)
+static void *map_library(int fd, struct dso *dso)
{
Ehdr buf[(896+sizeof(Ehdr))/sizeof(Ehdr)];
size_t phsize;
unsigned prot;
unsigned char *map, *base;
size_t dyn;
+ size_t tls_image=0;
size_t i;
ssize_t l = read(fd, buf, sizeof buf);
for (i=eh->e_phnum; i; i--, ph=(void *)((char *)ph+eh->e_phentsize)) {
if (ph->p_type == PT_DYNAMIC)
dyn = ph->p_vaddr;
+ 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;
+ }
if (ph->p_type != PT_LOAD) continue;
if (ph->p_vaddr < addr_min) {
addr_min = ph->p_vaddr;
}
if (!runtime) reclaim_gaps(base, (void *)((char *)buf + eh->e_phoff),
eh->e_phentsize, eh->e_phnum);
- *lenp = map_len;
- *basep = base;
- *dynp = dyn;
+ 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);
return map;
error:
munmap(map, map_len);
const char *pathname;
unsigned char *base, *map;
size_t dyno, map_len;
- struct dso *p;
+ struct dso *p, temp_dso = {0};
int fd;
struct stat st;
return p;
}
}
- map = map_library(fd, &map_len, &base, &dyno);
+ map = map_library(fd, &temp_dso);
close(fd);
if (!map) return 0;
- p = calloc(1, sizeof *p + strlen(pathname) + 1);
+ p = malloc(sizeof *p + strlen(pathname) + 1);
if (!p) {
munmap(map, map_len);
return 0;
}
-
- p->map = map;
- p->map_len = map_len;
- p->base = base;
- p->dynv = (void *)(base + dyno);
+ memcpy(p, &temp_dso, sizeof temp_dso);
decode_dyn(p);
-
+ if (p->tls_image) {
+ p->tls_id = ++tls_cnt;
+ tls_size += p->tls_size + p->tls_align + 8*sizeof(size_t) - 1
+ & -4*sizeof(size_t);
+ }
p->dev = st.st_dev;
p->ino = st.st_ino;
p->refcnt = 1;
{
}
+void *__copy_tls(unsigned char *mem, size_t cnt)
+{
+ struct dso *p;
+ void **dtv = (void *)mem;
+ dtv[0] = (void *)cnt;
+ mem = (void *)(dtv + cnt + 1);
+ for (p=tail; p; p=p->prev) {
+ if (p->tls_id-1 >= cnt) continue;
+ mem += -p->tls_len & (4*sizeof(size_t)-1);
+ mem += ((uintptr_t)p->tls_image - (uintptr_t)mem)
+ & (p->tls_align-1);
+ dtv[p->tls_id] = mem;
+ memcpy(mem, p->tls_image, p->tls_len);
+ mem += p->tls_size;
+ }
+ ((pthread_t)mem)->dtv = dtv;
+ return mem;
+}
+
+void *__tls_get_addr(size_t *p)
+{
+ pthread_t self = __pthread_self();
+ if ((size_t)self->dtv[0] < p[0]) {
+ // FIXME: obtain new DTV and TLS from the DSO
+ a_crash();
+ }
+ return (char *)self->dtv[p[0]] + p[1];
+}
+
void *__dynlink(int argc, char **argv)
{
size_t aux[AUX_CNT] = {0};
if (aux[AT_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 = (void *)aux[AT_PHDR];
for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
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 (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(
_exit(1);
}
runtime = 1;
- ehdr = (void *)map_library(fd, &app->map_len, &app->base, &dyno);
+ ehdr = (void *)map_library(fd, app);
if (!ehdr) {
dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
_exit(1);
close(fd);
lib->name = ldname;
app->name = argv[0];
- app->dynv = (void *)(app->base + dyno);
aux[AT_ENTRY] = ehdr->e_entry;
}
+ if (app->tls_size) {
+ app->tls_id = ++tls_cnt;
+ tls_size += app->tls_size+app->tls_align + 8*sizeof(size_t)-1
+ & -4*sizeof(size_t);
+ }
app->global = 1;
app->constructed = 1;
decode_dyn(app);
if (env_preload) load_preload(env_preload);
load_deps(app);
make_global(app);
+
+ /* Make an initial pass setting up TLS before performing relocs.
+ * This provides the TP-based offset of each DSO's TLS for
+ * use in TP-relative relocations. After relocations, we need
+ * to copy the TLS images again in case they had relocs. */
+ tls_size += sizeof(struct pthread) + 4*sizeof(size_t);
+ __libc.tls_size = tls_size;
+ __libc.tls_cnt = tls_cnt;
+ if (tls_cnt) {
+ struct dso *p;
+ 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, tls_cnt))) {
+ dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n",
+ argv[0], tls_size);
+ _exit(127);
+ }
+ for (p=head; p; p=p->next) {
+ if (!p->tls_id) continue;
+ p->tls_offset = (char *)__pthread_self()
+ - (char *)__pthread_self()->dtv[p->tls_id];
+ }
+ }
+
reloc_all(app->next);
reloc_all(app);
+ /* The initial DTV is located at the base of the memory
+ * allocated for TLS. Repeat copying TLS to pick up relocs. */
+ if (tls_cnt) __copy_tls((void *)__pthread_self()->dtv, tls_cnt);
+
if (ldso_fail) _exit(127);
if (ldd_mode) _exit(0);
do_init_fini(tail);
- if (!rtld_used) {
- free_all(head);
- free(sys_path);
- reclaim((void *)builtin_dsos, 0, sizeof builtin_dsos);
- }
-
errno = 0;
return (void *)aux[AT_ENTRY];
}
size_t i;
uint32_t h = 0, gh = 0;
Sym *sym;
- if (p == RTLD_NEXT) {
- for (p=head; p && (unsigned char *)ra-p->map>p->map_len; p=p->next);
- if (!p) p=head;
- void *res = find_sym(p->next, s, 0);
- if (!res) goto failed;
- return res;
- }
- if (p == head || p == RTLD_DEFAULT) {
- void *res = find_sym(head, s, 0);
- if (!res) goto failed;
- return res;
+ if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) {
+ if (p == RTLD_NEXT) {
+ for (p=head; p && (unsigned char *)ra-p->map>p->map_len; p=p->next);
+ if (!p) p=head;
+ }
+ struct symdef def = find_sym(p->next, s, 0);
+ if (!def.sym) goto failed;
+ return def.dso->base + def.sym->st_value;
}
if (p->ghashtab) {
gh = gnu_hash(s);
projects / musl / blobdiff