X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ldso%2Fdynlink.c;h=7b47b1635944432159a22f3fb02d27516910cc1c;hb=246f1c811448f37a44b41cd8df8d0ef9736d95f4;hp=7810356bd939d6b810c397587bd48bfbca4e6eb7;hpb=22daaea39f1cc5f7391f0a5cd84576ffb58c2860;p=musl

diff --git a/ldso/dynlink.c b/ldso/dynlink.c
index 7810356b..7b47b163 100644
--- a/ldso/dynlink.c
+++ b/ldso/dynlink.c
@@ -1,6 +1,5 @@
 #define _GNU_SOURCE
 #define SYSCALL_NO_TLS 1
-#include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
 #include <stddef.h>
@@ -21,11 +20,18 @@
 #include <semaphore.h>
 #include <sys/membarrier.h>
 #include "pthread_impl.h"
+#include "fork_impl.h"
 #include "libc.h"
 #include "dynlink.h"
-#include "malloc_impl.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))
@@ -79,7 +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;
@@ -107,6 +113,8 @@ struct symdef {
 	struct dso *dso;
 };
 
+typedef void (*stage3_func)(size_t *, size_t *);
+
 static struct builtin_tls {
 	char c;
 	struct pthread pt;
@@ -183,8 +191,14 @@ static void *laddr_pg(const struct dso *p, size_t v)
 	}
 	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 })
+static void (*fdbarrier(void *p))()
+{
+	void (*fd)();
+	__asm__("" : "=r"(fd) : "0"(p));
+	return fd;
+}
+#define fpaddr(p, v) fdbarrier((&(struct funcdesc){ \
+	laddr(p, v), (p)->got }))
 #else
 #define laddr(p, v) (void *)((p)->base + (v))
 #define laddr_pg(p, v) laddr(p, v)
@@ -196,7 +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];
 	}
 }
@@ -322,6 +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;
@@ -375,6 +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)) {
@@ -407,8 +456,6 @@ static void do_relocs(struct dso *dso, size_t *rel, size_t rel_size, size_t stri
 		}
 
 		switch(type) {
-		case REL_NONE:
-			break;
 		case REL_OFFSET:
 			addend -= (size_t)reloc_addr;
 		case REL_SYMBOLIC:
@@ -503,6 +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;
@@ -551,10 +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)
@@ -841,7 +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;
 		}
@@ -1055,13 +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 = "";
 				}
@@ -1326,13 +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;
@@ -1373,7 +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
@@ -1399,6 +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;
@@ -1457,6 +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;
 }
@@ -1465,7 +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++) {
@@ -1574,7 +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();
@@ -1594,13 +1699,14 @@ static void install_new_tls(void)
 
 hidden void __dls2(unsigned char *base, size_t *sp)
 {
+	size_t *auxv;
+	for (auxv=sp+1+*sp+1; *auxv; auxv++);
+	auxv++;
 	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++;
+			size_t aux[AUX_CNT];
 			decode_vec(auxv, aux, AUX_CNT);
 			if (aux[AT_BASE]) ldso.base = (void *)aux[AT_BASE];
 			else ldso.base = (void *)(aux[AT_PHDR] & -4096);
@@ -1646,8 +1752,8 @@ hidden void __dls2(unsigned char *base, size_t *sp)
 	 * symbolically as a barrier against moving the address
 	 * load across the above relocation processing. */
 	struct symdef dls2b_def = find_sym(&ldso, "__dls2b", 0);
-	if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls2b_def.sym-ldso.syms])(sp);
-	else ((stage3_func)laddr(&ldso, dls2b_def.sym->st_value))(sp);
+	if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls2b_def.sym-ldso.syms])(sp, auxv);
+	else ((stage3_func)laddr(&ldso, dls2b_def.sym->st_value))(sp, auxv);
 }
 
 /* Stage 2b sets up a valid thread pointer, which requires relocations
@@ -1656,11 +1762,13 @@ 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. */
 
-void __dls2b(size_t *sp)
+void __dls2b(size_t *sp, size_t *auxv)
 {
 	/* Setup early thread pointer in builtin_tls for ldso/libc itself to
 	 * use during dynamic linking. If possible it will also serve as the
 	 * thread pointer at runtime. */
+	search_vec(auxv, &__hwcap, AT_HWCAP);
+	libc.auxv = auxv;
 	libc.tls_size = sizeof builtin_tls;
 	libc.tls_align = tls_align;
 	if (__init_tp(__copy_tls((void *)builtin_tls)) < 0) {
@@ -1668,8 +1776,8 @@ void __dls2b(size_t *sp)
 	}
 
 	struct symdef dls3_def = find_sym(&ldso, "__dls3", 0);
-	if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp);
-	else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp);
+	if (DL_FDPIC) ((stage3_func)&ldso.funcdescs[dls3_def.sym-ldso.syms])(sp, auxv);
+	else ((stage3_func)laddr(&ldso, dls3_def.sym->st_value))(sp, auxv);
 }
 
 /* Stage 3 of the dynamic linker is called with the dynamic linker/libc
@@ -1677,10 +1785,10 @@ void __dls2b(size_t *sp)
  * process dependencies and relocations for the main application and
  * transfer control to its entry point. */
 
-void __dls3(size_t *sp)
+void __dls3(size_t *sp, size_t *auxv)
 {
 	static struct dso app, vdso;
-	size_t aux[AUX_CNT], *auxv;
+	size_t aux[AUX_CNT];
 	size_t i;
 	char *env_preload=0;
 	char *replace_argv0=0;
@@ -1693,10 +1801,7 @@ void __dls3(size_t *sp)
 	/* Find aux vector just past environ[] and use it to initialize
 	 * global data that may be needed before we can make syscalls. */
 	__environ = envp;
-	for (i=argc+1; argv[i]; i++);
-	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];
@@ -1709,6 +1814,9 @@ void __dls3(size_t *sp)
 		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. */
@@ -1784,7 +1892,7 @@ void __dls3(size_t *sp)
 			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);
@@ -1930,6 +2038,8 @@ void __dls3(size_t *sp)
 	 * 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
@@ -1940,7 +2050,7 @@ void __dls3(size_t *sp)
 	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;
@@ -1989,6 +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.");
@@ -2048,8 +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++)
@@ -2081,9 +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);
@@ -2277,7 +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);
 
@@ -2290,7 +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);
@@ -2304,3 +2420,7 @@ static void error(const char *fmt, ...)
 	__dl_vseterr(fmt, ap);
 	va_end(ap);
 }
+
+static void error_noop(const char *fmt, ...)
+{
+}