X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fldso%2Fdynlink.c;h=8d793f26b8914c311ce54756483486b6292a2c04;hb=4f8f038060739eca4c5cb97bb067529be96658d2;hp=6e79a77e67b90dc2ac3ce4891d38ae4aa8c6d484;hpb=a735f53e6ab094bce9b992dd3d3127fdb4ffdcc2;p=musl diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c index 6e79a77e..8d793f26 100644 --- a/src/ldso/dynlink.c +++ b/src/ldso/dynlink.c @@ -42,7 +42,11 @@ struct td_index { }; struct dso { +#if DL_FDPIC + struct fdpic_loadmap *loadmap; +#else unsigned char *base; +#endif char *name; size_t *dynv; struct dso *next, *prev; @@ -66,8 +70,8 @@ struct dso { 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; + struct tls_module tls; + size_t tls_id; size_t relro_start, relro_end; void **new_dtv; unsigned char *new_tls; @@ -75,6 +79,16 @@ struct dso { 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[]; }; @@ -85,7 +99,9 @@ struct symdef { int __init_tp(void *); void __init_libc(char **, char *); +void *__copy_tls(unsigned char *); +__attribute__((__visibility__("hidden"))) const char *__libc_get_version(void); static struct builtin_tls { @@ -109,12 +125,24 @@ static int noload; 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 = { ._m_type = PTHREAD_MUTEX_RECURSIVE }; +static struct fdpic_loadmap *app_loadmap; +static struct fdpic_dummy_loadmap app_dummy_loadmap; struct debug *_dl_debug_addr = &debug; +__attribute__((__visibility__("hidden"))) +void (*const __init_array_start)(void)=0, (*const __fini_array_start)(void)=0; + +__attribute__((__visibility__("hidden"))) +extern 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++); @@ -123,7 +151,20 @@ static int dl_strcmp(const char *l, const 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); +} +#define fpaddr(p, v) ((void (*)())&(struct funcdesc){ \ + laddr(p, v), (p)->got }) +#else #define laddr(p, v) (void *)((p)->base + (v)) +#define fpaddr(p, v) ((void (*)())laddr(p, v)) +#endif static void decode_vec(size_t *v, size_t *a, size_t cnt) { @@ -284,7 +325,7 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri } for (; rel_size; rel+=stride, rel_size-=stride*sizeof(size_t)) { - if (skip_relative && IS_RELATIVE(rel[1])) continue; + if (skip_relative && IS_RELATIVE(rel[1], dso->syms)) continue; type = R_TYPE(rel[1]); if (type == REL_NONE) continue; sym_index = R_SYM(rel[1]); @@ -293,7 +334,9 @@ 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->next : head; - def = find_sym(ctx, name, type==REL_PLT); + def = (sym->st_info&0xf) == STT_SECTION + ? (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)) { error("Error relocating %s: %s: symbol not found", @@ -349,6 +392,15 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri *(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; @@ -357,14 +409,14 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri break; #ifdef TLS_ABOVE_TP case REL_TPOFF: - *reloc_addr = tls_val + def.dso->tls_offset + TPOFF_K + addend; + *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; + *reloc_addr = tls_val - def.dso->tls.offset + addend; break; case REL_TPOFF_NEG: - *reloc_addr = def.dso->tls_offset - tls_val + addend; + *reloc_addr = def.dso->tls.offset - tls_val + addend; break; #endif case REL_TLSDESC: @@ -386,10 +438,10 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri } else { reloc_addr[0] = (size_t)__tlsdesc_static; #ifdef TLS_ABOVE_TP - reloc_addr[1] = tls_val + def.dso->tls_offset + reloc_addr[1] = tls_val + def.dso->tls.offset + TPOFF_K + addend; #else - reloc_addr[1] = tls_val - def.dso->tls_offset + reloc_addr[1] = tls_val - def.dso->tls.offset + addend; #endif } @@ -430,6 +482,7 @@ static void reclaim_gaps(struct dso *dso) Phdr *ph = dso->phdr; size_t phcnt = dso->phnum; + if (DL_FDPIC) return; // FIXME 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; @@ -441,8 +494,14 @@ static void reclaim_gaps(struct dso *dso) static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t off) { - char *q = mmap(p, n, prot, flags, fd, off); - if (q != MAP_FAILED || errno != EINVAL) return q; + static int no_map_fixed; + char *q; + 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); @@ -461,6 +520,22 @@ static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t of return p; } +static void unmap_library(struct dso *dso) +{ + if (dso->loadmap) { + size_t i; + for (i=0; iloadmap->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)]; @@ -468,6 +543,7 @@ static void *map_library(int fd, struct dso *dso) 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; @@ -503,14 +579,15 @@ static void *map_library(int fd, struct dso *dso) 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; + 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; + nsegs++; if (ph->p_vaddr < addr_min) { addr_min = ph->p_vaddr; off_start = ph->p_offset; @@ -523,6 +600,46 @@ static void *map_library(int fd, struct dso *dso) } } 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; ie_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; @@ -532,8 +649,14 @@ static void *map_library(int fd, struct dso *dso) * 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 = mmap((void *)addr_min, map_len, prot, MAP_PRIVATE, fd, off_start); + 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) { @@ -555,7 +678,8 @@ static void *map_library(int fd, struct dso *dso) dso->phentsize = eh->e_phentsize; } /* Reuse the existing mapping for the lowest-address LOAD */ - if ((ph->p_vaddr & -PAGE_SIZE) == addr_min) continue; + if ((ph->p_vaddr & -PAGE_SIZE) == addr_min && !DL_NOMMU_SUPPORT) + continue; 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; @@ -579,18 +703,17 @@ static void *map_library(int fd, struct dso *dso) goto error; break; } - dso->map = map; - dso->map_len = map_len; +done_mapping: dso->base = base; - dso->dynv = (void *)(base+dyn); - if (dso->tls_size) dso->tls_image = (void *)(base+tls_image); + dso->dynv = laddr(dso, dyn); + if (dso->tls.size) dso->tls.image = laddr(dso, tls_image); if (!runtime) reclaim_gaps(dso); free(allocated_buf); return map; noexec: errno = ENOEXEC; error: - if (map!=MAP_FAILED) munmap(map, map_len); + if (map!=MAP_FAILED) unmap_library(dso); free(allocated_buf); return 0; } @@ -695,15 +818,76 @@ static void decode_dyn(struct dso *p) if (dyn[0]&(1<hashtab = laddr(p, dyn[DT_HASH]); if (dyn[0]&(1<rpath_orig = (void *)(p->strings + dyn[DT_RPATH]); + p->rpath_orig = p->strings + dyn[DT_RPATH]; if (dyn[0]&(1<rpath_orig = (void *)(p->strings + dyn[DT_RUNPATH]); + p->rpath_orig = p->strings + dyn[DT_RUNPATH]; + if (dyn[0]&(1<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 p == MAP_FAILED ? 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; isyms[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]; @@ -839,8 +1023,8 @@ static struct dso *load_library(const char *name, struct dso *needed_by) * 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 + 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; @@ -848,7 +1032,7 @@ static struct dso *load_library(const char *name, struct dso *needed_by) } p = calloc(1, alloc_size); if (!p) { - munmap(map, temp_dso.map_len); + unmap_library(&temp_dso); return 0; } memcpy(p, &temp_dso, sizeof temp_dso); @@ -861,28 +1045,33 @@ static struct dso *load_library(const char *name, struct dso *needed_by) 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 (p->tls.image) { p->tls_id = ++tls_cnt; - tls_align = MAXP2(tls_align, p->tls_align); + 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 + ( (tls_align-1) & + -(tls_offset + (uintptr_t)p->tls.image) ); + 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; + 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; @@ -959,14 +1148,14 @@ static void reloc_all(struct dso *p) if (p->relocated) continue; decode_vec(p->dynv, dyn, DYN_CNT); 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], + 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, (void *)(p->base+dyn[DT_REL]), dyn[DT_RELSZ], 2); - do_relocs(p, (void *)(p->base+dyn[DT_RELA]), dyn[DT_RELASZ], 3); + 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(p->base+p->relro_start, p->relro_end-p->relro_start, PROT_READ) + 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); @@ -1001,7 +1190,7 @@ static void kernel_mapped_dso(struct dso *p) p->kernel_mapped = 1; } -static void do_fini() +void __libc_exit_fini() { struct dso *p; size_t dyn[DYN_CNT]; @@ -1015,7 +1204,7 @@ static void do_fini() } #ifndef NO_LEGACY_INITFINI if ((dyn[0] & (1<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; - void **dtv; - -#ifdef TLS_ABOVE_TP - 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); - - for (p=head; p; p=p->next) { - if (!p->tls_id) continue; - dtv[p->tls_id] = mem + p->tls_offset; - 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; +weak_alias(dl_debug_state, _dl_debug_state); - for (p=head; p; p=p->next) { - if (!p->tls_id) continue; - dtv[p->tls_id] = mem - p->tls_offset; - memcpy(dtv[p->tls_id], p->tls_image, p->tls_len); - } -#endif - dtv[0] = (void *)tls_cnt; - td->dtv = td->dtv_copy = dtv; - return td; +void __init_tls(size_t *auxv) +{ } __attribute__((__visibility__("hidden"))) @@ -1131,7 +1280,7 @@ void *__tls_get_new(size_t *v) /* Get new DTV space from new DSO if needed */ if (v[0] > (size_t)self->dtv[0]) { void **newdtv = p->new_dtv + - (v[0]+1)*sizeof(void *)*a_fetch_add(&p->new_dtv_idx,1); + (v[0]+1)*a_fetch_add(&p->new_dtv_idx,1); memcpy(newdtv, self->dtv, ((size_t)self->dtv[0]+1) * sizeof(void *)); newdtv[0] = (void *)v[0]; @@ -1142,12 +1291,12 @@ void *__tls_get_new(size_t *v) 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) + 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); + 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); + memcpy(mem, p->tls.image, p->tls.len); if (p->tls_id == v[0]) break; } __restore_sigs(&set); @@ -1156,6 +1305,8 @@ void *__tls_get_new(size_t *v) 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 + @@ -1175,30 +1326,48 @@ static void update_tls_size() * linker itself, but some of the relocations performed may need to be * replaced later due to copy relocations in the main program. */ +__attribute__((__visibility__("hidden"))) void __dls2(unsigned char *base, size_t *sp) { - Ehdr *ehdr = (void *)base; - ldso.base = base; + if (DL_FDPIC) { + void *p1 = (void *)sp[-2]; + void *p2 = (void *)sp[-1]; + if (!p1) { + size_t *auxv, aux[AUX_CNT]; + for (auxv=sp+1+*sp+1; *auxv; auxv++); auxv++; + 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.global = 1; ldso.phnum = ehdr->e_phnum; - ldso.phdr = (void *)(base + ehdr->e_phoff); + 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 = (void *)(base+dyn[DT_REL]); + 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])) symbolic_rel_cnt++; + 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; @@ -1212,7 +1381,8 @@ void __dls2(unsigned char *base, size_t *sp) * 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); + if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp); + else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp); } /* Stage 3 of the dynamic linker is called with the dynamic linker/libc @@ -1247,6 +1417,7 @@ _Noreturn void __dls3(size_t *sp) * use during dynamic linking. If possible it will also serve as the * thread pointer at runtime. */ libc.tls_size = sizeof builtin_tls; + libc.tls_align = tls_align; if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) { a_crash(); } @@ -1274,12 +1445,13 @@ _Noreturn void __dls3(size_t *sp) 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 = laddr(&app, tls_image); + 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<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; + } /* Attach to vdso, if provided by the kernel */ if (search_vec(auxv, &vdso_base, AT_SYSINFO_EHDR)) { @@ -1449,10 +1633,7 @@ _Noreturn void __dls3(size_t *sp) debug.state = 0; _dl_debug_state(); - __init_libc(envp, argv[0]); - atexit(do_fini); errno = 0; - do_init_fini(tail); CRTJMP((void *)aux[AT_ENTRY], argv-1); for(;;); @@ -1461,6 +1642,7 @@ _Noreturn void __dls3(size_t *sp) void *dlopen(const char *file, int mode) { struct dso *volatile p, *orig_tail, *next; + struct tls_module *orig_tls_tail; size_t orig_tls_cnt, orig_tls_offset, orig_tls_align; size_t i; int cs; @@ -1473,6 +1655,7 @@ void *dlopen(const char *file, int mode) __inhibit_ptc(); p = 0; + orig_tls_tail = tls_tail; orig_tls_cnt = tls_cnt; orig_tls_offset = tls_offset; orig_tls_align = tls_align; @@ -1487,17 +1670,20 @@ void *dlopen(const char *file, int mode) p->deps[i]->global = 0; 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; } + free(p->funcdescs); if (p->rpath != p->rpath_orig) free(p->rpath); free(p->deps); + unmap_library(p); free(p); } + if (!orig_tls_tail) libc.tls_head = 0; + tls_tail = orig_tls_tail; tls_cnt = orig_tls_cnt; tls_offset = orig_tls_offset; tls_align = orig_tls_align; @@ -1555,6 +1741,30 @@ static int invalid_dso_handle(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; iloadmap->nsegs; i++) { + if (a-p->loadmap->segs[i].p_vaddr + < p->loadmap->segs[i].p_memsz) + return p; + } + } else { + if (a-(size_t)p->map < p->map_len) + return p; + } + } + return 0; +} + void *__tls_get_addr(size_t *); static void *do_dlsym(struct dso *p, const char *s, void *ra) @@ -1566,7 +1776,7 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra) if (p == RTLD_DEFAULT) { p = head; } else if (p == RTLD_NEXT) { - for (p=head; p && (unsigned char *)ra-p->map>p->map_len; p=p->next); + p = addr2dso((size_t)ra); if (!p) p=head; p = p->next; } @@ -1574,6 +1784,8 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra) if (!def.sym) goto failed; if ((def.sym->st_info&0xf) == STT_TLS) return __tls_get_addr((size_t []){def.dso->tls_id, def.sym->st_value}); + 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 (invalid_dso_handle(p)) @@ -1587,6 +1799,8 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra) } if (sym && (sym->st_info&0xf) == STT_TLS) return __tls_get_addr((size_t []){p->tls_id, sym->st_value}); + 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); if (p->deps) for (i=0; p->deps[i]; i++) { @@ -1599,6 +1813,8 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra) } if (sym && (sym->st_info&0xf) == STT_TLS) return __tls_get_addr((size_t []){p->deps[i]->tls_id, sym->st_value}); + 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); } @@ -1607,44 +1823,34 @@ failed: return 0; } -int __dladdr(const void *addr, Dl_info *info) +int dladdr(const void *addr, Dl_info *info) { struct dso *p; - Sym *sym; + Sym *sym, *bestsym; uint32_t nsym; char *strings; - size_t i; void *best = 0; - char *bestname; pthread_rwlock_rdlock(&lock); - for (p=head; p && (unsigned char *)addr-p->map>p->map_len; p=p->next); + p = addr2dso((size_t)addr); pthread_rwlock_unlock(&lock); if (!p) return 0; sym = p->syms; strings = p->strings; - if (p->hashtab) { - nsym = p->hashtab[1]; - } else { - uint32_t *buckets; - uint32_t *hashval; - buckets = p->ghashtab + 4 + (p->ghashtab[2]*sizeof(size_t)/4); - sym += p->ghashtab[1]; - for (i = nsym = 0; i < p->ghashtab[0]; i++) { - if (buckets[i] > nsym) - nsym = buckets[i]; - } - if (nsym) { - nsym -= p->ghashtab[1]; - hashval = buckets + p->ghashtab[0] + nsym; - do nsym++; - while (!(*hashval++ & 1)); + nsym = count_syms(p); + + if (DL_FDPIC) { + size_t idx = ((size_t)addr-(size_t)p->funcdescs) + / sizeof(*p->funcdescs); + if (idx < nsym && (sym[idx].st_info&0xf) == STT_FUNC) { + best = p->funcdescs + idx; + bestsym = sym + idx; } } - for (; nsym; nsym--, sym++) { + if (!best) for (; nsym; nsym--, sym++) { if (sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES) && (1<<(sym->st_info>>4) & OK_BINDS)) { @@ -1652,7 +1858,7 @@ int __dladdr(const void *addr, Dl_info *info) if (symaddr > addr || symaddr < best) continue; best = symaddr; - bestname = strings + sym->st_name; + bestsym = sym; if (addr == symaddr) break; } @@ -1660,9 +1866,12 @@ int __dladdr(const void *addr, Dl_info *info) if (!best) return 0; + if (DL_FDPIC && (bestsym->st_info&0xf) == STT_FUNC) + best = p->funcdescs + (bestsym - p->syms); + info->dli_fname = p->name; info->dli_fbase = p->base; - info->dli_sname = bestname; + info->dli_sname = strings + bestsym->st_name; info->dli_saddr = best; return 1; @@ -1691,7 +1900,7 @@ int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void info.dlpi_adds = gencnt; info.dlpi_subs = 0; info.dlpi_tls_modid = current->tls_id; - info.dlpi_tls_data = current->tls_image; + info.dlpi_tls_data = current->tls.image; ret = (callback)(&info, sizeof (info), data); @@ -1719,10 +1928,6 @@ void *__dlsym(void *restrict p, const char *restrict s, void *restrict ra) error("Symbol not found: %s", s); return 0; } -int __dladdr (const void *addr, Dl_info *info) -{ - return 0; -} #endif int __dlinfo(void *dso, int req, void *res) @@ -1736,29 +1941,13 @@ int __dlinfo(void *dso, int req, void *res) return 0; } -char *dlerror() -{ - 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); -} +__attribute__((__visibility__("hidden"))) +void __dl_vseterr(const char *, va_list); static void error(const char *fmt, ...) { @@ -1773,19 +1962,6 @@ static void error(const char *fmt, ...) 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); + __dl_vseterr(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; }