From 60d37f690c54b5994939899d93bceb981c6bc2ee Mon Sep 17 00:00:00 2001
From: Martin Stein <martin.stein@genode-labs.com>
Date: Tue, 15 Oct 2019 14:19:31 +0200
Subject: [PATCH] packet_stream_*: fix missing dissolve on exception

When the construction of a member of Packet_stream_*::Rpc_object after
the _cap member threw an exception, the object was not dissolved from
the entrypoint although the Rpc_object vanished at this point. This was
because the call to 'manage()' happened in the initializer list (for the
_cap member instantiation). The destruction of the _cap member then did
not dissolve the object.

This first fix moves the call to 'manage()' into the constructor body
after the instantiation of all other members. A more sophisticated fix
would use some kind of 'Managed_object' life-time guard that manages an
object on construction and dissolves on destruction.

Ref #3525
---
 repos/os/include/packet_stream_rx/rpc_object.h | 9 ++++++---
 repos/os/include/packet_stream_tx/rpc_object.h | 8 +++++---
 2 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/repos/os/include/packet_stream_rx/rpc_object.h b/repos/os/include/packet_stream_rx/rpc_object.h
index 8366689ad..e3b255a54 100644
--- a/repos/os/include/packet_stream_rx/rpc_object.h
+++ b/repos/os/include/packet_stream_rx/rpc_object.h
@@ -26,7 +26,7 @@ class Packet_stream_rx::Rpc_object : public Genode::Rpc_object<CHANNEL, Rpc_obje
 	private:
 
 		Genode::Rpc_entrypoint     &_ep;
-		Genode::Capability<CHANNEL> _cap;
+		Genode::Capability<CHANNEL> _cap { };
 		typename CHANNEL::Source    _source;
 
 		Genode::Signal_context_capability _sigh_ready_to_submit;
@@ -48,11 +48,14 @@ class Packet_stream_rx::Rpc_object : public Genode::Rpc_object<CHANNEL, Rpc_obje
 		           Genode::Region_map           &rm,
 		           Genode::Range_allocator      &buffer_alloc,
 		           Genode::Rpc_entrypoint       &ep)
-		: _ep(ep), _cap(_ep.manage(this)), _source(ds, rm, buffer_alloc),
+		: _ep(ep), _source(ds, rm, buffer_alloc),
 
 		  /* init signal handlers with default handlers of source */
 		  _sigh_ready_to_submit(_source.sigh_ready_to_submit()),
-		  _sigh_ack_avail(_source.sigh_ack_avail()) { }
+		  _sigh_ack_avail(_source.sigh_ack_avail())
+		{
+			_cap = _ep.manage(this);
+		}
 
 		/**
 		 * Destructor
diff --git a/repos/os/include/packet_stream_tx/rpc_object.h b/repos/os/include/packet_stream_tx/rpc_object.h
index 02fdf4bbe..8c9abbf14 100644
--- a/repos/os/include/packet_stream_tx/rpc_object.h
+++ b/repos/os/include/packet_stream_tx/rpc_object.h
@@ -26,7 +26,7 @@ class Packet_stream_tx::Rpc_object : public Genode::Rpc_object<CHANNEL, Rpc_obje
 	private:
 
 		Genode::Rpc_entrypoint     &_ep;
-		Genode::Capability<CHANNEL> _cap;
+		Genode::Capability<CHANNEL> _cap { };
 		typename CHANNEL::Sink      _sink;
 
 		Genode::Signal_context_capability _sigh_ready_to_ack;
@@ -46,12 +46,14 @@ class Packet_stream_tx::Rpc_object : public Genode::Rpc_object<CHANNEL, Rpc_obje
 		           Genode::Region_map     &rm,
 		           Genode::Rpc_entrypoint &ep)
 		:
-			_ep(ep), _cap(_ep.manage(this)), _sink(ds, rm),
+			_ep(ep), _sink(ds, rm),
 
 			/* init signal handlers with default handlers of sink */
 			_sigh_ready_to_ack(_sink.sigh_ready_to_ack()),
 			_sigh_packet_avail(_sink.sigh_packet_avail())
-		{ }
+		{
+			_cap = _ep.manage(this);
+		}
 
 		/**
 		 * Destructor