X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;ds=sidebyside;f=src%2Fldso%2Fdynlink.c;h=e0013ec0eecfe698dd717135e79cb55b44214e78;hb=a9e85c0a5c690086c652f3a8ae9a109389f671a3;hp=e1c2ad7d883a4eaa3abc1d1baee7a85095ec18ec;hpb=c82f4a32ec694903a37d3f9e48da52486a470aa2;p=musl

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index e1c2ad7d..e0013ec0 100644
--- a/src/ldso/dynlink.c
+++ b/src/ldso/dynlink.c
@@ -1,4 +1,3 @@
-#ifdef __PIC__
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -18,6 +17,10 @@
 #include <ctype.h>
 #include <dlfcn.h>
 
+static int errflag;
+
+#ifdef __PIC__
+
 #include "reloc.h"
 
 #if ULONG_MAX == 0xffffffff
@@ -47,8 +50,9 @@ struct dso
 	size_t map_len;
 	dev_t dev;
 	ino_t ino;
-	int global;
-	int relocated;
+	char global;
+	char relocated;
+	char constructed;
 	struct dso **deps;
 	char *name;
 	char buf[];
@@ -471,6 +475,20 @@ static size_t find_dyn(Phdr *ph, size_t cnt, size_t stride)
 	return 0;
 }
 
+static void do_init_fini(struct dso *p)
+{
+	size_t dyn[DYN_CNT] = {0};
+	for (; p; p=p->prev) {
+		if (p->constructed) return;
+		decode_vec(p->dynv, dyn, DYN_CNT);
+		if (dyn[0] & (1<<DT_FINI))
+			atexit((void (*)(void))(p->base + dyn[DT_FINI]));
+		if (dyn[0] & (1<<DT_INIT))
+			((void (*)(void))(p->base + dyn[DT_INIT]))();
+		p->constructed = 1;
+	}
+}
+
 void *__dynlink(int argc, char **argv)
 {
 	size_t *auxv, aux[AUX_CNT] = {0};
@@ -511,12 +529,16 @@ void *__dynlink(int argc, char **argv)
 		ehdr->e_phnum, ehdr->e_phentsize));
 	decode_dyn(lib);
 
-	/* Assume base address of 0 for the main program. This is not
-	 * valid for PIE code; we will have to search the PHDR to get
-	 * the correct load address in the PIE case (not yet supported). */
+	/* Find load address of the main program, via AT_PHDR vs PT_PHDR. */
 	app->base = 0;
+	phdr = (void *)aux[AT_PHDR];
+	for (i=aux[AT_PHNUM]; i; i--, phdr=(void *)((char *)phdr + aux[AT_PHENT])) {
+		if (phdr->p_type == PT_PHDR)
+			app->base = (void *)(aux[AT_PHDR] - phdr->p_vaddr);
+	}
 	app->name = argv[0];
 	app->global = 1;
+	app->constructed = 1;
 	app->dynv = (void *)(app->base + find_dyn(
 		(void *)aux[AT_PHDR], aux[AT_PHNUM], aux[AT_PHENT]));
 	decode_dyn(app);
@@ -560,10 +582,13 @@ void *__dynlink(int argc, char **argv)
 		ehdr->e_phentsize, ehdr->e_phnum);
 
 	/* Load preload/needed libraries, add their symbols to the global
-	 * namespace, and perform all remaining relocations. */
+	 * namespace, and perform all remaining relocations. The main
+	 * program must be relocated LAST since it may contain copy
+	 * relocations which depend on libraries' relocations. */
 	if (env_preload) load_preload(env_preload);
 	load_deps(app);
 	make_global(app);
+	reloc_all(app->next);
 	reloc_all(app);
 
 	/* Switch to runtime mode: any further failures in the dynamic
@@ -571,6 +596,9 @@ void *__dynlink(int argc, char **argv)
 	 * error. If the dynamic loader (dlopen) will not be used, free
 	 * all memory used by the dynamic linker. */
 	runtime = 1;
+
+	do_init_fini(tail);
+
 	if (!rtld_used) {
 		free_all(head);
 		free(sys_path);
@@ -585,9 +613,11 @@ void *dlopen(const char *file, int mode)
 {
 	struct dso *volatile p, *orig_tail = tail, *next;
 	size_t i;
+	int cs;
 
 	if (!file) return head;
 
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
 	pthread_rwlock_wrlock(&lock);
 
 	if (setjmp(rtld_fail)) {
@@ -603,12 +633,13 @@ void *dlopen(const char *file, int mode)
 		}
 		tail = orig_tail;
 		tail->next = 0;
-		pthread_rwlock_unlock(&lock);
-		return 0;
-	}
+		p = 0;
+	} else p = load_library(file);
 
-	p = load_library(file);
-	if (!p) goto end;
+	if (!p) {
+		errflag = 1;
+		goto end;
+	}
 
 	/* First load handling */
 	if (!p->deps) {
@@ -630,8 +661,10 @@ void *dlopen(const char *file, int mode)
 		p->global = 1;
 	}
 
+	do_init_fini(tail);
 end:
 	pthread_rwlock_unlock(&lock);
+	pthread_setcancelstate(cs, 0);
 	return p;
 }
 
@@ -645,8 +678,11 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra)
 		if (!p) p=head;
 		p=p->next;
 	}
-	if (p == head || p == RTLD_DEFAULT)
-		return find_sym(head, s, 0);
+	if (p == head || p == RTLD_DEFAULT) {
+		void *res = find_sym(head, s, 0);
+		if (!res) errflag = 1;
+		return res;
+	}
 	h = hash(s);
 	sym = lookup(s, h, p->syms, p->hashtab, p->strings);
 	if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
@@ -657,6 +693,7 @@ static void *do_dlsym(struct dso *p, const char *s, void *ra)
 		if (sym && sym->st_value && (1<<(sym->st_info&0xf) & OK_TYPES))
 			return p->deps[i]->base + sym->st_value;
 	}
+	errflag = 1;
 	return 0;
 }
 
@@ -668,9 +705,21 @@ void *__dlsym(void *p, const char *s, void *ra)
 	pthread_rwlock_unlock(&lock);
 	return res;
 }
+#else
+void *dlopen(const char *file, int mode)
+{
+	return 0;
+}
+void *__dlsym(void *p, const char *s, void *ra)
+{
+	return 0;
+}
+#endif
 
 char *dlerror()
 {
+	if (!errflag) return 0;
+	errflag = 0;
 	return "unknown error";
 }
 
@@ -678,4 +727,3 @@ int dlclose(void *p)
 {
 	return 0;
 }
-#endif