Changeset b454a22 in mainline

Timestamp:

2016-07-03T22:11:52Z (8 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

659ebd86

Parents:

92c07dc

Message:

libdrv: Do proper reference counting on fun in driver_connection_gen()

driver_connection_gen() should add a reference when it starts to work
with fun and drop it when before it returns. Otherwise it is possible
for fun to become a dangling pointer.

File:

• uspace/lib/drv/generic/driver.c (modified) (4 diffs)

uspace/lib/drv/generic/driver.c

@@ -335 +335 @@
         fibril_mutex_lock(&functions_mutex);
         ddf_fun_t *fun = driver_get_function(handle);
+        if (fun != NULL)
+                fun_add_ref(fun);
         fibril_mutex_unlock(&functions_mutex);
-        /* XXX Need a lock on fun */
         
         if (fun == NULL) {
@@ -348 +349 @@
                 /* Driver has a custom connection handler. */
                 (*fun->conn_handler)(iid, icall, (void *)fun);
+                fun_del_ref(fun);
                 return;
         }
@@ -362 +364 @@
         
         async_answer_0(iid, ret);
-        if (ret != EOK)
+        if (ret != EOK) {
+                fun_del_ref(fun);
                 return;
+        }
         
         while (true) {
@@ -376 +380 @@
                                 (*fun->ops->close)(fun);
                         async_answer_0(callid, EOK);
+                        fun_del_ref(fun);
                         return;
                 }