Fix a problem with RTLD_TRACE flag to dlopen(3), which sometimes can return

even if there was no error occured (when trying to dlopen(3) object that
already linked into executable which does dlopen(3) call). This is more
proper fix for `ldd /usr/lib/libc.so' problem, because the new behaviour
conforms to documentation.

Remove workaround from ldd.c (rev.1.32).

PR:		35099
Submitted by:	Nathan Hawkins <utsl@quic.net>
MFC after:	1 week

2 files changed, 12 insertions, 11 deletions

diff --git a/libexec/rtld-elf/rtld.c b/libexec/rtld-elf/rtld.c
index a007ff5..d7f243a 100644
--- a/libexec/rtld-elf/rtld.c
+++ b/libexec/rtld-elf/rtld.c
@@ -1605,11 +1605,8 @@ dlopen(const char *name, int mode)
 	    assert(*old_obj_tail == obj);
 
 	    result = load_needed_objects(obj);
-	    if (result != -1 && ld_tracing) {
-		trace_loaded_objects(obj);
-		wlock_release();
-		exit(0);
-	    }
+	    if (result != -1 && ld_tracing)
+		goto trace;
 
 	    if (result == -1 ||
 	      (init_dag(obj), relocate_objects(obj, mode == RTLD_NOW,
@@ -1623,7 +1620,8 @@ dlopen(const char *name, int mode)
 		/* Make list of init functions to call. */
 		initlist_add_objects(obj, &obj->next, &initlist);
 	    }
-	}
+	} else if (ld_tracing)
+	    goto trace;
     }
 
     GDB_STATE(RT_CONSISTENT,obj ? &obj->linkmap : NULL);
@@ -1635,6 +1633,10 @@ dlopen(const char *name, int mode)
     objlist_clear(&initlist);
     wlock_release();
     return obj;
+trace:
+    trace_loaded_objects(obj);
+    wlock_release();
+    exit(0);
 }
 
 void *
diff --git a/usr.bin/ldd/ldd.c b/usr.bin/ldd/ldd.c
index 68f9988..8e5e5d2 100644
--- a/usr.bin/ldd/ldd.c
+++ b/usr.bin/ldd/ldd.c
@@ -220,13 +220,12 @@ main(int argc, char *argv[])
 			}
 			break;
 		case 0:
-			if (is_shlib) {
-				if (dlopen(*argv, RTLD_TRACE))
-					_exit(0);	/* libc.so */
-				warnx("%s: %s", *argv, dlerror());
-			} else {
+			if (is_shlib == 0) {
 				execl(*argv, *argv, (char *)NULL);
 				warn("%s", *argv);
+			} else {
+				dlopen(*argv, RTLD_TRACE);
+				warnx("%s: %s", *argv, dlerror());
 			}
 			_exit(1);
 		}