X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=src%2Fldso%2Fdynlink.c;h=3f3316aaf4ccde3c4ff7e8880d562484f99efc2a;hb=94167cafd5a8f4f8309c3f82f5bda17f4767cb60;hp=6ff8850c8eb89d55ac4c16799bc12e5e09ca0d45;hpb=f2baf4d7b8be043b231ecf7fc611247196acd9f5;p=musl

diff --git a/src/ldso/dynlink.c b/src/ldso/dynlink.c
index 6ff8850c..3f3316aa 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 +17,11 @@
 #include <ctype.h>
 #include <dlfcn.h>
 
+static int errflag;
+static char errbuf[128];
+
+#ifdef __PIC__
+
 #include "reloc.h"
 
 #if ULONG_MAX == 0xffffffff
@@ -34,15 +38,24 @@ typedef Elf64_Sym Sym;
 #define R_SYM(x) ((x)>>32)
 #endif
 
-struct dso
-{
+struct debug {
+	int ver;
+	void *head;
+	void (*bp)(void);
+	int state;
+	void *base;
+};
+
+struct dso {
+	unsigned char *base;
+	char *name;
+	size_t *dynv;
 	struct dso *next, *prev;
+
 	int refcnt;
-	size_t *dynv;
 	Sym *syms;
 	uint32_t *hashtab;
 	char *strings;
-	unsigned char *base;
 	unsigned char *map;
 	size_t map_len;
 	dev_t dev;
@@ -51,16 +64,22 @@ struct dso
 	char relocated;
 	char constructed;
 	struct dso **deps;
-	char *name;
 	char buf[];
 };
 
+struct __pthread;
+struct __pthread *__pthread_self_init(void);
+
 static struct dso *head, *tail, *libc;
 static char *env_path, *sys_path, *r_path;
 static int rtld_used;
+static int ssp_used;
 static int runtime;
 static jmp_buf rtld_fail;
 static pthread_rwlock_t lock;
+static struct debug debug;
+
+struct debug *_dl_debug_addr = &debug;
 
 #define AUX_CNT 24
 #define DYN_CNT 34
@@ -104,6 +123,7 @@ static void *find_sym(struct dso *dso, const char *s, int need_def)
 	void *def = 0;
 	if (h==0x6b366be && !strcmp(s, "dlopen")) rtld_used = 1;
 	if (h==0x6b3afd && !strcmp(s, "dlsym")) rtld_used = 1;
+	if (h==0x595a4cc && !strcmp(s, "__stack_chk_fail")) ssp_used = 1;
 	for (; dso; dso=dso->next) {
 		Sym *sym;
 		if (!dso->global) continue;
@@ -139,8 +159,11 @@ static void do_relocs(unsigned char *base, size_t *rel, size_t rel_size, size_t
 			ctx = IS_COPY(type) ? dso->next : dso;
 			sym_val = (size_t)find_sym(ctx, name, IS_PLT(type));
 			if (!sym_val && sym->st_info>>4 != STB_WEAK) {
+				snprintf(errbuf, sizeof errbuf,
+					"Error relocating %s: %s: symbol not found",
+					dso->name, name);
 				if (runtime) longjmp(rtld_fail, 1);
-				dprintf(2, "%s: symbol not found\n", name);
+				dprintf(2, "%s\n", errbuf);
 				_exit(127);
 			}
 			sym_size = sym->st_size;
@@ -402,9 +425,11 @@ static void load_deps(struct dso *p)
 			if (p->dynv[i] != DT_NEEDED) continue;
 			dep = load_library(p->strings + p->dynv[i+1]);
 			if (!dep) {
-				if (runtime) longjmp(rtld_fail, 1);
-				dprintf(2, "%s: %m (needed by %s)\n",
+				snprintf(errbuf, sizeof errbuf,
+					"Error loading shared library %s: %m (needed by %s)",
 					p->strings + p->dynv[i+1], p->name);
+				if (runtime) longjmp(rtld_fail, 1);
+				dprintf(2, "%s\n", errbuf);
 				_exit(127);
 			}
 			if (runtime) {
@@ -486,6 +511,10 @@ static void do_init_fini(struct dso *p)
 	}
 }
 
+void _dl_debug_state(void)
+{
+}
+
 void *__dynlink(int argc, char **argv)
 {
 	size_t *auxv, aux[AUX_CNT] = {0};
@@ -594,6 +623,16 @@ void *__dynlink(int argc, char **argv)
 	 * all memory used by the dynamic linker. */
 	runtime = 1;
 
+	for (i=0; app->dynv[i]; i+=2)
+		if (app->dynv[i]==DT_DEBUG)
+			app->dynv[i+1] = (size_t)&debug;
+	debug.ver = 1;
+	debug.bp = _dl_debug_state;
+	debug.head = head;
+	debug.base = lib->base;
+	debug.state = 0;
+	_dl_debug_state();
+
 	do_init_fini(tail);
 
 	if (!rtld_used) {
@@ -602,6 +641,8 @@ void *__dynlink(int argc, char **argv)
 		reclaim((void *)builtin_dsos, 0, sizeof builtin_dsos);
 	}
 
+	if (ssp_used) __pthread_self_init();
+
 	errno = 0;
 	return (void *)aux[AT_ENTRY];
 }
@@ -631,11 +672,16 @@ void *dlopen(const char *file, int mode)
 		tail = orig_tail;
 		tail->next = 0;
 		p = 0;
+		errflag = 1;
 		goto end;
-	}
+	} else p = load_library(file);
 
-	p = load_library(file);
-	if (!p) goto end;
+	if (!p) {
+		snprintf(errbuf, sizeof errbuf,
+			"Error loading shared library %s: %m", file);
+		errflag = 1;
+		goto end;
+	}
 
 	/* First load handling */
 	if (!p->deps) {
@@ -657,6 +703,8 @@ void *dlopen(const char *file, int mode)
 		p->global = 1;
 	}
 
+	_dl_debug_state();
+
 	do_init_fini(tail);
 end:
 	pthread_rwlock_unlock(&lock);
@@ -674,8 +722,11 @@ 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))
@@ -686,6 +737,8 @@ 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;
+	snprintf(errbuf, sizeof errbuf, "Symbol not found: %s", s);
 	return 0;
 }
 
@@ -710,7 +763,9 @@ void *__dlsym(void *p, const char *s, void *ra)
 
 char *dlerror()
 {
-	return "unknown error";
+	if (!errflag) return 0;
+	errflag = 0;
+	return errbuf;
 }
 
 int dlclose(void *p)