UCS/TEST: Remove entry from configuration list when library is unloaded - v1.6.x

NEWS

@@ -25,6 +25,7 @@ Bugfixes:
 - RPM Spec file cleanup
 - Fixing compilation issues with most recent clang and gcc compilers
 - Fixing the wrong name of aliases
+- Fix segfault when libuct.so is reloaded - issue #3558
 
 Tested configurations:
 - RDMA: MLNX_OFED 4.5, distribution inbox drivers, rdma-core 22.1

contrib/test_jenkins.sh

@@ -847,6 +847,10 @@ test_ucs_dlopen() {
 	# Make sure UCM is not unloaded
 	echo "==== Running UCS dlopen test with memhooks ===="
 	./test/apps/test_ucs_dlopen
+
+	# Test global config list integrity after loading/unloading of UCT
+	echo "==== Running test_dlopen_cfg_print ===="
+	./test/apps/test_dlopen_cfg_print
 }
 
 test_ucp_dlopen() {

src/ucs/config/parser.h

@@ -88,14 +88,19 @@ typedef struct ucs_config_bw_spec {
 
 
 #define UCS_CONFIG_REGISTER_TABLE(_fields, _name, _prefix, _type) \
+    static ucs_config_global_list_entry_t _fields##_config_entry; \
     UCS_STATIC_INIT { \
+        ucs_config_global_list_entry_t *entry = &_fields##_config_entry; \
         extern ucs_list_link_t ucs_config_global_list; \
-        static ucs_config_global_list_entry_t entry; \
-        entry.fields = _fields; \
-        entry.name   = _name; \
-        entry.prefix = _prefix; \
-        entry.size   = sizeof(_type); \
-        ucs_list_add_tail(&ucs_config_global_list, &entry.list); \
+        entry->fields = _fields; \
+        entry->name   = _name; \
+        entry->prefix = _prefix; \
+        entry->size   = sizeof(_type); \
+        ucs_list_add_tail(&ucs_config_global_list, &entry->list); \
+    } \
+    \
+    UCS_STATIC_CLEANUP { \
+        ucs_list_del(&_fields##_config_entry.list); \
     }
 
 

test/apps/Makefile.am

@@ -13,7 +13,8 @@ endif
 noinst_PROGRAMS = \
 	test_ucp_dlopen \
 	test_ucs_dlopen \
-	test_link_map
+	test_link_map \
+	test_dlopen_cfg_print
 
 objdir = $(shell sed -n -e 's/^objdir=\(.*\)$$/\1/p' $(LIBTOOL))
 
@@ -34,6 +35,13 @@ test_link_map_CPPFLAGS = $(BASE_CPPFLAGS)
 test_link_map_CFLAGS   = $(BASE_CFLAGS)
 test_link_map_LDADD    = -ldl $(top_builddir)/src/ucp/libucp.la
 
+test_dlopen_cfg_print_SOURCES  = test_dlopen_cfg_print.c
+test_dlopen_cfg_print_CPPFLAGS = $(BASE_CPPFLAGS) -g \
+	-DUCS_LIB_PATH=$(abs_top_builddir)/src/ucs/$(objdir)/libucs.so \
+	-DUCT_LIB_PATH=$(abs_top_builddir)/src/uct/$(objdir)/libuct.so
+test_dlopen_cfg_print_CFLAGS   = $(BASE_CFLAGS)
+test_dlopen_cfg_print_LDADD    = -ldl
+
 if HAVE_TCMALLOC
 noinst_PROGRAMS       += test_tcmalloc
 test_tcmalloc_SOURCES  = test_tcmalloc.c

test/apps/test_dlopen_cfg_print.c

@@ -0,0 +1,54 @@
+/**
+ * Copyright (C) Mellanox Technologies Ltd. 2019.  ALL RIGHTS RESERVED.
+ *
+ * See file LICENSE for terms.
+ */
+
+#include <stdlib.h>
+#include <dlfcn.h>
+#include <stdio.h>
+
+#define _QUOTE(x) #x
+#define QUOTE(x) _QUOTE(x)
+
+
+static void* do_dlopen_or_exit(const char *filename)
+{
+    void *handle;
+
+    (void)dlerror();
+    printf("opening '%s'\n", filename);
+    handle = dlopen(filename, RTLD_LAZY);
+    if (handle == NULL) {
+        fprintf(stderr, "failed to open %s: %s\n", filename,
+                dlerror());
+        exit(1);
+    }
+
+    return handle;
+}
+
+int main(int argc, char **argv)
+{
+    const char *ucs_filename = QUOTE(UCS_LIB_PATH);
+    const char *uct_filename = QUOTE(UCT_LIB_PATH);
+    void *ucs_handle, *uct_handle;
+    int i;
+
+    /* unload and reload uct while ucs is loaded
+     * would fail if uct global vars are kept on global lists in ucs */
+    ucs_handle = do_dlopen_or_exit(ucs_filename);
+    for (i = 0; i < 2; ++i) {
+        uct_handle = do_dlopen_or_exit(uct_filename);
+        dlclose(uct_handle);
+    }
+
+    /* print all config table, to force going over the global list in ucs */
+    void (*print_all_opts)(FILE*, int) =
+        dlsym(ucs_handle, "ucs_config_parser_print_all_opts");
+    print_all_opts(stdout, 0);
+    dlclose(ucs_handle);
+
+    printf("done\n");
+    return 0;
+}