If sending a lot of data and/or the other peer is not reading it, then
socket buffers can overflow. This is communicated from the kernel by
returning EAGAIN. In GIO, it is modelled by g_output_stream_write()
and g_socket_send_message() returning G_IO_ERROR_WOULD_BLOCK.
It is also problematic that that we're using synchronous IO in the
shared GDBus IO thread. It means that one GDBusConnection can lock up
others.
It turns out that by porting from g_output_stream_write() to
g_output_stream_write_async() we fix the EAGAIN issue. For GSocket, we
still need to handle things manually (by creating a GSource) as
g_socket_send_message() is used.
We check the new behavior in Michael's producer/consumer test case (at
/gdbus/overflow in gdbus-peer.c) added in the last commit.
Also add a test case that sends and receives a 20 MiB message.
Also add a new `transport' G_DBUS_DEBUG option so it is easy to
inspect partial writes:
$ G_DBUS_DEBUG=transport ./gdbus-connection -p /gdbus/connection/large_message
[...]
========================================================================
GDBus-debug:Transport:
>>>> WROTE 128000 bytes of message with serial 4 and
size 20971669 from offset 0 on a GSocketOutputStream
========================================================================
GDBus-debug:Transport:
>>>> WROTE 128000 bytes of message with serial 4 and
size 20971669 from offset 128000 on a GSocketOutputStream
========================================================================
GDBus-debug:Transport:
>>>> WROTE 128000 bytes of message with serial 4 and
size 20971669 from offset 256000 on a GSocketOutputStream
[...]
========================================================================
GDBus-debug:Transport:
>>>> WROTE 43669 bytes of message with serial 4 and
size 20971669 from offset 20928000 on a GSocketOutputStream
[...]
========================================================================
GDBus-debug:Transport:
<<<< READ 16 bytes of message with serial 3 and
size 20971620 to offset 0 from a GSocketInputStream
========================================================================
GDBus-debug:Transport:
<<<< READ 15984 bytes of message with serial 3 and
size 20971620 to offset 16 from a GSocketInputStream
========================================================================
GDBus-debug:Transport:
<<<< READ 16000 bytes of message with serial 3 and
size 20971620 to offset 16000 from a GSocketInputStream
[...]
========================================================================
GDBus-debug:Transport:
<<<< READ 144000 bytes of message with serial 3 and
size 20971620 to offset 20720000 from a GSocketInputStream
========================================================================
GDBus-debug:Transport:
<<<< READ 107620 bytes of message with serial 3 and
size 20971620 to offset 20864000 from a GSocketInputStream
OK
https://bugzilla.gnome.org/show_bug.cgi?id=626748
Signed-off-by: David Zeuthen <davidz@redhat.com>
This patch fixes this problem
Syscall param socketcall.sendmsg(msg.msg_control) points to uninitialised byte(s)
at 0x3D5B00EA60: __sendmsg_nocancel (syscall-template.S:82)
by 0x53F9790: g_socket_send_message (gsocket.c:2918)
by 0x540FDD0: g_unix_connection_send_credentials (gunixconnection.c:351)
by 0x542B93F: _g_dbus_auth_run_client (gdbusauth.c:618)
by 0x5438001: initable_init (gdbusconnection.c:2191)
by 0x53E09CC: g_initable_init (ginitable.c:105)
by 0x543F6E9: g_bus_get_sync (gdbusconnection.c:6091)
by 0x402C7E: test_connection_life_cycle (gdbus-connection.c:126)
by 0x4C7CABB: test_case_run (gtestutils.c:1174)
by 0x4C7CD84: g_test_run_suite_internal (gtestutils.c:1223)
by 0x4C7CE49: g_test_run_suite_internal (gtestutils.c:1233)
by 0x4C7CE49: g_test_run_suite_internal (gtestutils.c:1233)
Address 0x7fefff9fc is on thread 1's stack
Signed-off-by: David Zeuthen <davidz@redhat.com>
Previously if a GSocketConnection had a blocking GSocket, it would
sometimes block during asynchonous I/O, and if it had a non-blocking
socket, it would sometimes return G_IO_ERROR_WOULD_BLOCK from
synchronous I/O. This fixes the connection to not depend on the socket
state.
https://bugzilla.gnome.org/show_bug.cgi?id=616458
g_socket_client_connect_async() was always leaking its GCancellable,
and would also leak any GSocket that eventually failed to connect
after returning G_IO_ERROR_PENDING.
GSocket has a timeout flag now, but when using GSocketClient there was
no way to set the timeout until after connecting (or failing). Fix
that by adding a timeout property to GSocketClient.
Because g_simple_async_report_[g]error_in_idle() don't take a source tag
parameter, code that uses them can't currently use
g_simple_async_result_is_valid() (at least, not for the error case).
Bug 602417
