Fix #637, fix OS_ModuleUnload for static modules

Ensure that the handle is not NULL before invoking dlclose(). In particular the handle will be NULL for static modules.
nasa · Oct 30, 2020 · 902f09a · 902f09a
1 parent 5a8f0af
commit 902f09a
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Showing 2 changed files with 24 additions and 18 deletions.
diff --git a/src/os/portable/os-impl-posix-dl-loader.c b/src/os/portable/os-impl-posix-dl-loader.c
@@ -90,20 +90,23 @@ int32 OS_ModuleLoad_Impl(uint32 module_id, const char *translated_path)
  *-----------------------------------------------------------------*/
 int32 OS_ModuleUnload_Impl(uint32 module_id)
 {
-    int32 status = OS_ERROR;
+    int32 status = OS_SUCCESS;
 
     /*
     ** Attempt to close/unload the module
     */
-    dlerror();
-    if (dlclose(OS_impl_module_table[module_id].dl_handle) == 0)
-    {
-        OS_impl_module_table[module_id].dl_handle = NULL;
-        status                                    = OS_SUCCESS;
-    }
-    else
+    if (OS_impl_module_table[module_id].dl_handle != NULL)
     {
-        OS_DEBUG("Error unloading shared library: %s\n", dlerror());
+        dlerror();
+        if (dlclose(OS_impl_module_table[module_id].dl_handle) == 0)
+        {
+            OS_impl_module_table[module_id].dl_handle = NULL;
+        }
+        else
+        {
+            OS_DEBUG("Error unloading shared library: %s\n", dlerror());
+            status = OS_ERROR;
+        }
     }
 
     return status;

diff --git a/src/os/rtems/src/os-impl-loader.c b/src/os/rtems/src/os-impl-loader.c
@@ -179,20 +179,23 @@ int32 OS_ModuleLoad_Impl(uint32 module_id, const char *translated_path)
  *-----------------------------------------------------------------*/
 int32 OS_ModuleUnload_Impl(uint32 module_id)
 {
-    int32 status = OS_ERROR;
+    int32 status = OS_SUCCESS;
 
     /*
     ** Attempt to close/unload the module
     */
-    dlerror();
-    if (dlclose(OS_impl_module_table[module_id].dl_handle) == 0)
-    {
-        OS_impl_module_table[module_id].dl_handle = NULL;
-        status                                    = OS_SUCCESS;
-    }
-    else
+    if (OS_impl_module_table[module_id].dl_handle != NULL)
     {
-        OS_DEBUG("Error unloading shared library: %s\n", dlerror());
+        dlerror();
+        if (dlclose(OS_impl_module_table[module_id].dl_handle) == 0)
+        {
+            OS_impl_module_table[module_id].dl_handle = NULL;
+        }
+        else
+        {
+            OS_DEBUG("Error unloading shared library: %s\n", dlerror());
+            status = OS_ERROR;
+        }
     }
 
     return status;