Changeset e06da7e in mainline for kernel/generic/src/ipc/sysipc.c

Timestamp:

2009-03-07T15:59:32Z (16 years ago)

Author:

Jakub Jermar <jakub@…>

Branches:

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

Children:

411b6a6

Parents:

b11ee88

Message:

If the server cannot receive a call because it supplied a bad userspace address, the kernel will immediately answer the call with EPARTY.

File:

• kernel/generic/src/ipc/sysipc.c (modified) (1 diff)

kernel/generic/src/ipc/sysipc.c

@@ -937 +937 @@
          * copy whole call->data, not only call->data.args */
         if (STRUCT_TO_USPACE(calldata, &call->data)) {
-                /* XXX
-                 * To avoid deadlocks in synchronous calls
-                 * this should be replaced by discarding
-                 * the call and notifying the caller.
+                /*
+                 * The callee will not receive this call and no one else has
+                 * a chance to answer it. Reply with the EPARTY error code.
                  */
+                ipc_data_t saved_data;
+                int saveddata = 0;
+
+                if (answer_need_old(call)) {
+                        memcpy(&saved_data, &call->data, sizeof(call->data));
+                        saveddata = 1;
+                }
+                
+                IPC_SET_RETVAL(call->data, EPARTY);
+                (void) answer_preprocess(call, saveddata ? &saved_data : NULL);
+                ipc_answer(&TASK->answerbox, call);
                 return 0;
         }