diff options
| -rw-r--r-- | src/ldso/dynlink.c | 87 |
1 files changed, 48 insertions, 39 deletions
diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c index e07db33a..21c3ebad 100644 --- a/src/ldso/dynlink.c +++ b/src/ldso/dynlink.c @@ -40,6 +40,9 @@ typedef Elf64_Sym Sym; #define R_SYM(x) ((x)>>32) #endif +#define MAXP2(a,b) (-(-(a)&-(b))) +#define ALIGN(x,y) ((x)+(y)-1 & -(y)) + struct debug { int ver; void *head; @@ -97,7 +100,7 @@ static jmp_buf rtld_fail; static pthread_rwlock_t lock; static struct debug debug; static size_t *auxv; -static size_t tls_cnt, tls_size; +static size_t tls_cnt, tls_offset, tls_start, tls_align = 4*sizeof(size_t); static pthread_mutex_t init_fini_lock = { ._m_type = PTHREAD_MUTEX_RECURSIVE }; struct debug *_dl_debug_addr = &debug; @@ -525,8 +528,11 @@ static struct dso *load_library(const char *name) if (pathname != name) p->shortname = strrchr(p->name, '/')+1; 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); + tls_align = MAXP2(tls_align, p->tls_align); + 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; 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)); @@ -683,21 +689,26 @@ void _dl_debug_state(void) 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; - mem = (void *)(dtv + tls_cnt + 1); - for (p=tail; p; p=p->prev) { + + mem += __libc.tls_size - sizeof(struct pthread); + mem -= (uintptr_t)mem & (tls_align-1); + mem -= tls_start; + td = (pthread_t)mem; + + for (p=head; p; p=p->next) { if (!p->tls_id) 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; + dtv[p->tls_id] = mem - p->tls_offset; + memcpy(dtv[p->tls_id], p->tls_image, p->tls_len); } - ((pthread_t)mem)->dtv = dtv; - return mem; + td->dtv = dtv; + return td; } void *__tls_get_addr(size_t *v) @@ -737,11 +748,18 @@ void *__tls_get_addr(size_t *v) (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_size); + memcpy(mem, p->tls_image, p->tls_len); pthread_sigmask(SIG_SETMASK, &set, 0); return mem + v[1]; } +static void update_tls_size() +{ + size_t below_tp = (1+tls_cnt) * sizeof(void *) + tls_offset; + size_t above_tp = sizeof(struct pthread) + tls_start + tls_align; + __libc.tls_size = ALIGN(below_tp + above_tp, tls_align); +} + void *__dynlink(int argc, char **argv) { size_t aux[AUX_CNT] = {0}; @@ -849,9 +867,11 @@ void *__dynlink(int argc, char **argv) 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->tls_id = tls_cnt = 1; + tls_offset = app->tls_offset = app->tls_size; + tls_start = -((uintptr_t)app->tls_image + app->tls_size) + & (app->tls_align-1); + tls_align = MAXP2(tls_align, app->tls_align); } app->global = 1; app->constructed = 1; @@ -900,12 +920,10 @@ void *__dynlink(int argc, char **argv) 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; + reloc_all(app->next); + reloc_all(app); + + update_tls_size(); if (tls_cnt) { struct dso *p; void *mem = mmap(0, __libc.tls_size, PROT_READ|PROT_WRITE, @@ -913,23 +931,11 @@ void *__dynlink(int argc, char **argv) if (mem==MAP_FAILED || !__install_initial_tls(__copy_tls(mem))) { dprintf(2, "%s: Error getting %zu bytes thread-local storage: %m\n", - argv[0], tls_size); + argv[0], __libc.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); - if (ldso_fail) _exit(127); if (ldd_mode) _exit(0); @@ -963,7 +969,7 @@ void *__dynlink(int argc, char **argv) void *dlopen(const char *file, int mode) { struct dso *volatile p, *orig_tail, *next; - size_t orig_tls_cnt; + size_t orig_tls_cnt, orig_tls_offset, orig_tls_align; size_t i; int cs; @@ -975,6 +981,8 @@ void *dlopen(const char *file, int mode) p = 0; orig_tls_cnt = tls_cnt; + orig_tls_offset = tls_offset; + orig_tls_align = tls_align; orig_tail = tail; if (setjmp(rtld_fail)) { @@ -989,7 +997,8 @@ void *dlopen(const char *file, int mode) free(p); } tls_cnt = orig_tls_cnt; - tls_size = __libc.tls_size; + tls_offset = orig_tls_offset; + tls_align = orig_tls_align; tail = orig_tail; tail->next = 0; p = 0; @@ -1024,7 +1033,7 @@ void *dlopen(const char *file, int mode) p->global = 1; } - __libc.tls_size = tls_size; + update_tls_size(); if (ssp_used) __init_ssp(auxv); |