fixup a big 'ol memory leak in search_for_named_library()

ldso/ldso/dl-elf.c

@@ -136,20 +136,33 @@ static struct elf_resolve *
 search_for_named_library(const char *name, int secure, const char *path_list,
 	struct dyn_elf **rpnt)
 {
-	char *path, *path_n;
-	char mylibname[2050];
+	char *path, *path_n, *mylibname;
 	struct elf_resolve *tpnt;
-	int done = 0;
+	int done;
 
 	if (path_list==NULL)
 		return NULL;
 
-	/* We need a writable copy of this string */
-	path = _dl_strdup(path_list);
-	if (!path) {
+	/* We need a writable copy of this string, but we don't
+	 * need this allocated permanently since we don't want
+	 * to leak memory, so use alloca to put path on the stack */
+	done = _dl_strlen(path_list);
+	path = alloca(done + 1);
+
+	/* another bit of local storage */
+	mylibname = alloca(2050);
+
+	/* gcc inlines alloca using a single instruction adjusting
+	 * the stack pointer and no stack overflow check and thus
+	 * no NULL error return.  No point leaving in dead code... */
+#if 0
+	if (!path || !mylibname) {
 		_dl_dprintf(2, "Out of memory!\n");
 		_dl_exit(0);
 	}
+#endif
+
+	_dl_strcpy(path, path_list);
 
 	/* Unlike ldd.c, don't bother to eliminate double //s */
 
@@ -157,6 +170,7 @@ search_for_named_library(const char *name, int secure, const char *path_list,
 	/* : at the beginning or end of path maps to CWD */
 	/* :: anywhere maps CWD */
 	/* "" maps to CWD */ 
+	done = 0;
 	path_n = path;
 	do {
 		if (*path == 0) {