clean up dns_parse_callback
[musl] / ldso / dynlink.c
index f692691..7b47b16 100644 (file)
@@ -1,6 +1,5 @@
 #define _GNU_SOURCE
 #define SYSCALL_NO_TLS 1
-#include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
 #include <stddef.h>
 #include <semaphore.h>
 #include <sys/membarrier.h>
 #include "pthread_impl.h"
+#include "fork_impl.h"
 #include "libc.h"
 #include "dynlink.h"
 
-static void error(const char *, ...);
+#define malloc __libc_malloc
+#define calloc __libc_calloc
+#define realloc __libc_realloc
+#define free __libc_free
+
+static void error_impl(const char *, ...);
+static void error_noop(const char *, ...);
+static void (*error)(const char *, ...) = error_noop;
 
 #define MAXP2(a,b) (-(-(a)&-(b)))
 #define ALIGN(x,y) ((x)+(y)-1 & -(y))
@@ -78,7 +85,7 @@ struct dso {
        struct dso **deps, *needed_by;
        size_t ndeps_direct;
        size_t next_dep;
-       int ctor_visitor;
+       pthread_t ctor_visitor;
        char *rpath_orig, *rpath;
        struct tls_module tls;
        size_t tls_id;
@@ -203,7 +210,8 @@ static void decode_vec(size_t *v, size_t *a, size_t cnt)
        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];
+               if (v[0] < 8*sizeof(long))
+                       a[0] |= 1UL<<v[0];
                a[v[0]] = v[1];
        }
 }
@@ -329,6 +337,39 @@ static struct symdef find_sym(struct dso *dso, const char *s, int need_def)
        return find_sym2(dso, s, need_def, 0);
 }
 
+static struct symdef get_lfs64(const char *name)
+{
+       static const char *p, lfs64_list[] =
+               "aio_cancel\0aio_error\0aio_fsync\0aio_read\0aio_return\0"
+               "aio_suspend\0aio_write\0alphasort\0creat\0fallocate\0"
+               "fgetpos\0fopen\0freopen\0fseeko\0fsetpos\0fstat\0"
+               "fstatat\0fstatfs\0fstatvfs\0ftello\0ftruncate\0ftw\0"
+               "getdents\0getrlimit\0glob\0globfree\0lio_listio\0"
+               "lockf\0lseek\0lstat\0mkostemp\0mkostemps\0mkstemp\0"
+               "mkstemps\0mmap\0nftw\0open\0openat\0posix_fadvise\0"
+               "posix_fallocate\0pread\0preadv\0prlimit\0pwrite\0"
+               "pwritev\0readdir\0scandir\0sendfile\0setrlimit\0"
+               "stat\0statfs\0statvfs\0tmpfile\0truncate\0versionsort\0"
+               "__fxstat\0__fxstatat\0__lxstat\0__xstat\0";
+       size_t l;
+       char buf[16];
+       for (l=0; name[l]; l++) {
+               if (l >= sizeof buf) goto nomatch;
+               buf[l] = name[l];
+       }
+       if (!strcmp(name, "readdir64_r"))
+               return find_sym(&ldso, "readdir_r", 1);
+       if (l<2 || name[l-2]!='6' || name[l-1]!='4')
+               goto nomatch;
+       buf[l-=2] = 0;
+       for (p=lfs64_list; *p; p++) {
+               if (!strcmp(buf, p)) return find_sym(&ldso, buf, 1);
+               while (*p) p++;
+       }
+nomatch:
+       return (struct symdef){ 0 };
+}
+
 static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stride)
 {
        unsigned char *base = dso->base;
@@ -382,6 +423,7 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri
                        def = (sym->st_info>>4) == STB_LOCAL
                                ? (struct symdef){ .dso = dso, .sym = sym }
                                : find_sym(ctx, name, type==REL_PLT);
+                       if (!def.sym) def = get_lfs64(name);
                        if (!def.sym && (sym->st_shndx != SHN_UNDEF
                            || sym->st_info>>4 != STB_WEAK)) {
                                if (dso->lazy && (type==REL_PLT || type==REL_GOT)) {
@@ -508,6 +550,23 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri
        }
 }
 
+static void do_relr_relocs(struct dso *dso, size_t *relr, size_t relr_size)
+{
+       unsigned char *base = dso->base;
+       size_t *reloc_addr;
+       for (; relr_size; relr++, relr_size-=sizeof(size_t))
+               if ((relr[0]&1) == 0) {
+                       reloc_addr = laddr(dso, relr[0]);
+                       *reloc_addr++ += (size_t)base;
+               } else {
+                       int i = 0;
+                       for (size_t bitmap=relr[0]; (bitmap>>=1); i++)
+                               if (bitmap&1)
+                                       reloc_addr[i] += (size_t)base;
+                       reloc_addr += 8*sizeof(size_t)-1;
+               }
+}
+
 static void redo_lazy_relocs()
 {
        struct dso *p = lazy_head, *next;
@@ -556,10 +615,25 @@ static void reclaim_gaps(struct dso *dso)
        }
 }
 
+static ssize_t read_loop(int fd, void *p, size_t n)
+{
+       for (size_t i=0; i<n; ) {
+               ssize_t l = read(fd, (char *)p+i, n-i);
+               if (l<0) {
+                       if (errno==EINTR) continue;
+                       else return -1;
+               }
+               if (l==0) return i;
+               i += l;
+       }
+       return n;
+}
+
 static void *mmap_fixed(void *p, size_t n, int prot, int flags, int fd, off_t off)
 {
        static int no_map_fixed;
        char *q;
+       if (!n) return p;
        if (!no_map_fixed) {
                q = mmap(p, n, prot, flags|MAP_FIXED, fd, off);
                if (!DL_NOMMU_SUPPORT || q != MAP_FAILED || errno != EINVAL)
@@ -846,7 +920,7 @@ static int fixup_rpath(struct dso *p, char *buf, size_t buf_size)
                case ENOENT:
                case ENOTDIR:
                case EACCES:
-                       break;
+                       return 0;
                default:
                        return -1;
                }
@@ -1060,13 +1134,17 @@ static struct dso *load_library(const char *name, struct dso *needed_by)
                                snprintf(etc_ldso_path, sizeof etc_ldso_path,
                                        "%.*s/etc/ld-musl-" LDSO_ARCH ".path",
                                        (int)prefix_len, prefix);
-                               FILE *f = fopen(etc_ldso_path, "rbe");
-                               if (f) {
-                                       if (getdelim(&sys_path, (size_t[1]){0}, 0, f) <= 0) {
+                               fd = open(etc_ldso_path, O_RDONLY|O_CLOEXEC);
+                               if (fd>=0) {
+                                       size_t n = 0;
+                                       if (!fstat(fd, &st)) n = st.st_size;
+                                       if ((sys_path = malloc(n+1)))
+                                               sys_path[n] = 0;
+                                       if (!sys_path || read_loop(fd, sys_path, n)<0) {
                                                free(sys_path);
                                                sys_path = "";
                                        }
-                                       fclose(f);
+                                       close(fd);
                                } else if (errno != ENOENT) {
                                        sys_path = "";
                                }
@@ -1331,13 +1409,17 @@ static void reloc_all(struct dso *p)
                        2+(dyn[DT_PLTREL]==DT_RELA));
                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(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);
-                       if (runtime) longjmp(*rtld_fail, 1);
+               if (!DL_FDPIC)
+                       do_relr_relocs(p, laddr(p, dyn[DT_RELR]), dyn[DT_RELRSZ]);
+
+               if (head != &ldso && p->relro_start != p->relro_end) {
+                       long ret = __syscall(SYS_mprotect, laddr(p, p->relro_start),
+                               p->relro_end-p->relro_start, PROT_READ);
+                       if (ret != 0 && ret != -ENOSYS) {
+                               error("Error relocating %s: RELRO protection failed: %m",
+                                       p->name);
+                               if (runtime) longjmp(*rtld_fail, 1);
+                       }
                }
 
                p->relocated = 1;
@@ -1378,7 +1460,7 @@ void __libc_exit_fini()
 {
        struct dso *p;
        size_t dyn[DYN_CNT];
-       int self = __pthread_self()->tid;
+       pthread_t self = __pthread_self();
 
        /* Take both locks before setting shutting_down, so that
         * either lock is sufficient to read its value. The lock
@@ -1404,6 +1486,17 @@ void __libc_exit_fini()
        }
 }
 
+void __ldso_atfork(int who)
+{
+       if (who<0) {
+               pthread_rwlock_wrlock(&lock);
+               pthread_mutex_lock(&init_fini_lock);
+       } else {
+               pthread_mutex_unlock(&init_fini_lock);
+               pthread_rwlock_unlock(&lock);
+       }
+}
+
 static struct dso **queue_ctors(struct dso *dso)
 {
        size_t cnt, qpos, spos, i;
@@ -1462,6 +1555,13 @@ static struct dso **queue_ctors(struct dso *dso)
        }
        queue[qpos] = 0;
        for (i=0; i<qpos; i++) queue[i]->mark = 0;
+       for (i=0; i<qpos; i++)
+               if (queue[i]->ctor_visitor && queue[i]->ctor_visitor->tid < 0) {
+                       error("State of %s is inconsistent due to multithreaded fork\n",
+                               queue[i]->name);
+                       free(queue);
+                       if (runtime) longjmp(*rtld_fail, 1);
+               }
 
        return queue;
 }
@@ -1470,7 +1570,7 @@ static void do_init_fini(struct dso **queue)
 {
        struct dso *p;
        size_t dyn[DYN_CNT], i;
-       int self = __pthread_self()->tid;
+       pthread_t self = __pthread_self();
 
        pthread_mutex_lock(&init_fini_lock);
        for (i=0; (p=queue[i]); i++) {
@@ -1579,7 +1679,7 @@ static void install_new_tls(void)
 
        /* Install new dtv for each thread. */
        for (j=0, td=self; !j || td!=self; j++, td=td->next) {
-               td->dtv = td->dtv_copy = newdtv[j];
+               td->dtv = newdtv[j];
        }
 
        __tl_unlock();
@@ -1714,6 +1814,9 @@ void __dls3(size_t *sp, size_t *auxv)
                env_preload = getenv("LD_PRELOAD");
        }
 
+       /* Activate error handler function */
+       error = error_impl;
+
        /* 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. */
@@ -1789,7 +1892,7 @@ void __dls3(size_t *sp, size_t *auxv)
                        dprintf(2, "%s: cannot load %s: %s\n", ldname, argv[0], strerror(errno));
                        _exit(1);
                }
-               Ehdr *ehdr = (void *)map_library(fd, &app);
+               Ehdr *ehdr = map_library(fd, &app);
                if (!ehdr) {
                        dprintf(2, "%s: %s: Not a valid dynamic program\n", ldname, argv[0]);
                        _exit(1);
@@ -1935,6 +2038,8 @@ void __dls3(size_t *sp, size_t *auxv)
         * possibility of incomplete replacement. */
        if (find_sym(head, "malloc", 1).dso != &ldso)
                __malloc_replaced = 1;
+       if (find_sym(head, "aligned_alloc", 1).dso != &ldso)
+               __aligned_alloc_replaced = 1;
 
        /* Switch to runtime mode: any further failures in the dynamic
         * linker are a reportable failure rather than a fatal startup
@@ -1945,7 +2050,7 @@ void __dls3(size_t *sp, size_t *auxv)
        debug.bp = dl_debug_state;
        debug.head = head;
        debug.base = ldso.base;
-       debug.state = 0;
+       debug.state = RT_CONSISTENT;
        _dl_debug_state();
 
        if (replace_argv0) argv[0] = replace_argv0;
@@ -1994,6 +2099,9 @@ void *dlopen(const char *file, int mode)
        pthread_rwlock_wrlock(&lock);
        __inhibit_ptc();
 
+       debug.state = RT_ADD;
+       _dl_debug_state();
+
        p = 0;
        if (shutting_down) {
                error("Cannot dlopen while program is exiting.");
@@ -2053,8 +2161,9 @@ void *dlopen(const char *file, int mode)
        load_deps(p);
        extend_bfs_deps(p);
        pthread_mutex_lock(&init_fini_lock);
-       if (!p->constructed) ctor_queue = queue_ctors(p);
+       int constructed = p->constructed;
        pthread_mutex_unlock(&init_fini_lock);
+       if (!constructed) ctor_queue = queue_ctors(p);
        if (!p->relocated && (mode & RTLD_LAZY)) {
                prepare_lazy(p);
                for (i=0; p->deps[i]; i++)
@@ -2086,9 +2195,10 @@ void *dlopen(const char *file, int mode)
        update_tls_size();
        if (tls_cnt != orig_tls_cnt)
                install_new_tls();
-       _dl_debug_state();
        orig_tail = tail;
 end:
+       debug.state = RT_CONSISTENT;
+       _dl_debug_state();
        __release_ptc();
        if (p) gencnt++;
        pthread_rwlock_unlock(&lock);
@@ -2282,7 +2392,8 @@ 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_id ? 0 :
+                       __tls_get_addr((tls_mod_off_t[]){current->tls_id,0});
 
                ret = (callback)(&info, sizeof (info), data);
 
@@ -2295,7 +2406,7 @@ int dl_iterate_phdr(int(*callback)(struct dl_phdr_info *info, size_t size, void
        return ret;
 }
 
-static void error(const char *fmt, ...)
+static void error_impl(const char *fmt, ...)
 {
        va_list ap;
        va_start(ap, fmt);
@@ -2309,3 +2420,7 @@ static void error(const char *fmt, ...)
        __dl_vseterr(fmt, ap);
        va_end(ap);
 }
+
+static void error_noop(const char *fmt, ...)
+{
+}