X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ldso%2Fdynlink.c;h=7ac0bf7552bc2aac596ec6ffb24f23217714202a;hb=022f27d541af68f047d367ad9d93f941135555c1;hp=255ace2de61605fb8ec17f63f2f38175b3a9d300;hpb=e612d094b1d27e1d61940e58d8aaeb249c54e768;p=musl diff --git a/ldso/dynlink.c b/ldso/dynlink.c index 255ace2d..7ac0bf75 100644 --- a/ldso/dynlink.c +++ b/ldso/dynlink.c @@ -1,4 +1,5 @@ #define _GNU_SOURCE +#define SYSCALL_NO_TLS 1 #include #include #include @@ -30,6 +31,7 @@ static void error(const char *, ...); #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; @@ -84,7 +86,6 @@ struct dso { size_t relro_start, relro_end; uintptr_t *new_dtv; unsigned char *new_tls; - volatile int new_dtv_idx, new_tls_idx; struct td_index *td_index; struct dso *fini_next; char *shortname; @@ -134,6 +135,8 @@ 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; @@ -280,12 +283,16 @@ static Sym *gnu_lookup_filtered(uint32_t h1, uint32_t *hashtab, struct dso *dso, #define ARCH_SYM_REJECT_UND(s) 0 #endif -static struct symdef find_sym(struct dso *dso, const char *s, int need_def) +#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}; - for (; dso; dso=dso->syms_next) { + 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); @@ -310,6 +317,11 @@ static struct symdef find_sym(struct dso *dso, const char *s, int need_def) 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; @@ -360,7 +372,7 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri sym = syms + sym_index; name = strings + sym->st_name; ctx = type==REL_COPY ? head->syms_next : head; - def = (sym->st_info&0xf) == STT_SECTION + 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 @@ -387,7 +399,7 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri tls_val = def.sym ? def.sym->st_value : 0; if ((type == REL_TPOFF || type == REL_TPOFF_NEG) - && runtime && def.dso->tls_id > static_tls_cnt) { + && 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); @@ -404,6 +416,9 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri 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; @@ -447,7 +462,7 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri #endif case REL_TLSDESC: if (stride<3) addend = reloc_addr[1]; - if (runtime && def.dso->tls_id > static_tls_cnt) { + if (def.dso->tls_id > static_tls_cnt) { struct td_index *new = malloc(sizeof *new); if (!new) { error( @@ -917,7 +932,7 @@ static void *dl_mmap(size_t n) #else p = (void *)__syscall(SYS_mmap, 0, n, prot, flags, -1, 0); #endif - return p == MAP_FAILED ? 0 : p; + return (unsigned long)p > -4096UL ? 0 : p; } static void makefuncdescs(struct dso *p) @@ -1122,9 +1137,9 @@ static struct dso *load_library(const char *name, struct dso *needed_by) p->tls_id = ++tls_cnt; tls_align = MAXP2(tls_align, p->tls.align); #ifdef TLS_ABOVE_TP - p->tls.offset = tls_offset + ( (tls_align-1) & - -(tls_offset + (uintptr_t)p->tls.image) ); - tls_offset += p->tls.size; + 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) @@ -1404,7 +1419,10 @@ static struct dso **queue_ctors(struct dso *dso) p->mark = 0; } cnt++; /* termination slot */ - stack = queue = calloc(cnt, sizeof *queue); + 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"); @@ -1415,6 +1433,7 @@ static struct dso **queue_ctors(struct dso *dso) /* 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; @@ -1454,7 +1473,6 @@ static void do_init_fini(struct dso **queue) pthread_cond_wait(&ctor_cond, &init_fini_lock); if (p->ctor_visitor || p->constructed) continue; - if (p->constructed) continue; p->ctor_visitor = self; decode_vec(p->dynv, dyn, DYN_CNT); @@ -1486,7 +1504,8 @@ static void do_init_fini(struct dso **queue) void __libc_start_init(void) { do_init_fini(main_ctor_queue); - if (!__malloc_replaced) free(main_ctor_queue); + if (!__malloc_replaced && main_ctor_queue != builtin_ctor_queue) + free(main_ctor_queue); main_ctor_queue = 0; } @@ -1637,7 +1656,7 @@ hidden void __dls2(unsigned char *base, size_t *sp) * so that loads of the thread pointer and &errno can be pure/const and * thereby hoistable. */ -_Noreturn void __dls2b(size_t *sp) +void __dls2b(size_t *sp) { /* Setup early thread pointer in builtin_tls for ldso/libc itself to * use during dynamic linking. If possible it will also serve as the @@ -1658,7 +1677,7 @@ _Noreturn void __dls2b(size_t *sp) * process dependencies and relocations for the main application and * transfer control to its entry point. */ -_Noreturn void __dls3(size_t *sp) +void __dls3(size_t *sp) { static struct dso app, vdso; size_t aux[AUX_CNT], *auxv; @@ -1678,6 +1697,8 @@ _Noreturn void __dls3(size_t *sp) libc.auxv = auxv = (void *)(argv+i+1); decode_vec(auxv, aux, AUX_CNT); __hwcap = aux[AT_HWCAP]; + 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]); @@ -1787,10 +1808,9 @@ _Noreturn void __dls3(size_t *sp) app.tls_id = tls_cnt = 1; #ifdef TLS_ABOVE_TP app.tls.offset = GAP_ABOVE_TP; - app.tls.offset += -GAP_ABOVE_TP & (app.tls.align-1); - tls_offset = app.tls.offset + app.tls.size - + ( -((uintptr_t)app.tls.image + app.tls.size) - & (app.tls.align-1) ); + 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) @@ -1820,6 +1840,7 @@ _Noreturn void __dls3(size_t *sp) 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) @@ -1841,6 +1862,7 @@ _Noreturn void __dls3(size_t *sp) 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; @@ -1864,19 +1886,28 @@ _Noreturn void __dls3(size_t *sp) * code can see to perform. */ main_ctor_queue = queue_ctors(&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); - + /* 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) { - void *initial_tls = calloc(libc.tls_size, 1); + 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(); } @@ -1890,7 +1921,6 @@ _Noreturn void __dls3(size_t *sp) 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); @@ -1990,8 +2020,9 @@ void *dlopen(const char *file, int mode) free(p->deps); unmap_library(p); free(p); - free(ctor_queue); } + 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; @@ -2107,58 +2138,27 @@ static void *addr2dso(size_t a) static void *do_dlsym(struct dso *p, const char *s, void *ra) { - size_t i; - uint32_t h = 0, gh = 0, *ght; - Sym *sym; - if (p == head || p == RTLD_DEFAULT || p == RTLD_NEXT) { - if (p == RTLD_DEFAULT) { - p = head; - } else if (p == RTLD_NEXT) { - p = addr2dso((size_t)ra); - if (!p) p=head; - p = p->next; - } - struct symdef def = find_sym(p, s, 0); - if (!def.sym) goto failed; - if ((def.sym->st_info&0xf) == STT_TLS) - return __tls_get_addr((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); - } - if (__dl_invalid_handle(p)) + 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; - if ((ght = p->ghashtab)) { - gh = gnu_hash(s); - sym = gnu_lookup(gh, ght, p, s); - } else { - h = sysv_hash(s); - sym = sysv_lookup(s, h, p); - } - if (sym && (sym->st_info&0xf) == STT_TLS) - return __tls_get_addr((tls_mod_off_t []){p->tls_id, sym->st_value-DTP_OFFSET}); - if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC) - return p->funcdescs + (sym - p->syms); - if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES)) - return laddr(p, sym->st_value); - for (i=0; p->deps[i]; i++) { - if ((ght = p->deps[i]->ghashtab)) { - if (!gh) gh = gnu_hash(s); - sym = gnu_lookup(gh, ght, p->deps[i], s); - } else { - if (!h) h = sysv_hash(s); - sym = sysv_lookup(s, h, p->deps[i]); - } - if (sym && (sym->st_info&0xf) == STT_TLS) - return __tls_get_addr((tls_mod_off_t []){p->deps[i]->tls_id, sym->st_value-DTP_OFFSET}); - if (DL_FDPIC && sym && sym->st_shndx && (sym->st_info&0xf) == STT_FUNC) - return p->deps[i]->funcdescs + (sym - p->deps[i]->syms); - if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES)) - return laddr(p->deps[i], sym->st_value); - } -failed: - error("Symbol not found: %s", s); - return 0; + } 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) @@ -2206,7 +2206,7 @@ int dladdr(const void *addr_arg, Dl_info *info) } } - if (bestsym && besterr > bestsym->st_size-1) { + if (best && besterr > bestsym->st_size-1) { best = 0; bestsym = 0; }