[ADC] crash on invalid utf-8 string (linux)

[New Thread 0xb462db90 (LWP 7666)]
BufferedSocket::run() start 0x870b7d8
BufferedSocket::connect() 0x870b7d8
threadConnect adc.volsk.san.ru:12000

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0xb57ccb90 (LWP 7659)]
0xb788f067 in g_markup_escape_text () from /usr/lib/libglib-2.0.so.0
(gdb) bt full
#0 0xb788f067 in g_markup_escape_text () from /usr/lib/libglib-2.0.so.0
No symbol table info available.
#1 0xb7c96b5f in gtk_widget_set_property (object=0x86d7ad8, prop_id=21,
    value=0xb57cc214, pspec=0x83164c0)
    at /build/buildd/gtk+2.0-2.12.9/gtk/gtkwidget.c:2447
 saved_flags = <value optimized out>
 tooltip_markup = (gchar *) 0x0
 tooltip_text = (const gchar *) 0x86e9e50 "\b0\203��>\n"
 widget = <value optimized out>
#2 0xb7918c26 in g_object_set_valist () from /usr/lib/libgobject-2.0.so.0
No symbol table info available.
#3 0xb79191e6 in g_object_set () from /usr/lib/libgobject-2.0.so.0
No symbol table info available.
#4 0xb7c8b031 in IA__gtk_widget_set_tooltip_text (widget=0x86d7ad8,
    text=0x86ca1d4 "Hub: VOLSK - �������� ���")
    at /build/buildd/gtk+2.0-2.12.9/gtk/gtkwidget.c:9609
 __PRETTY_FUNCTION__ = "IA__gtk_widget_set_tooltip_text"
#5 0x080558d5 in BookEntry::setLabel_gui (this=0x86e33a0, text=@0xb57cc340)
    at linux/bookentry.cc:87
 child = (GtkWidget *) 0x8708810
 len = -1250114808
#6 0x080aaaaf in Func1<Hub, std::string>::call (this=0x869b818)
    at linux/func.hh:70
---Type <return> to continue, or q <return> to quit---
No locals.
#7 0x0814e4be in WulforManager::processGuiQueue (this=0x8317e08)
    at linux/wulformanager.cc:181
 func = (FuncBase *) 0x869b818
#8 0x0814e567 in WulforManager::threadFunc_gui (data=0x8317e08)
    at linux/wulformanager.cc:148
 man = (WulforManager *) 0x8317e08
#9 0xb78b2d2f in ?? () from /usr/lib/libglib-2.0.so.0
No symbol table info available.
#10 0xb7f5d4fb in start_thread () from /lib/tls/i686/cmov/libpthread.so.0
No symbol table info available.
#11 0xb76b6e5e in clone () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
(gdb)

There could be a bug in the hub, since it seems like invalid utf-8 is transferred as hub description.

GTK crashes because it receives an invalid utf-8 string. The code in hub.cc assumes that dcpp checks this, which happens for NMDC but not for ADC, at least not for the hub description.

Shouldn't this be fixed in the dcpp/ instead? In AdcHub::on(Line) maybe before anything else is done? I assume that the adchub should only send (valid) UTF-8 and not binary data or use any other encoding. Validating it when it comes in would save us the trouble later.

--RZ

Yes, changing dcpp would be better, and ADC is limited to utf8. Do you know a non-glib function to validate utf-8? There's iconv, but it would be better if we could avoid making a copy of each string.

This needs to be fixed in the DC++ core. The core should always validate data it receives from external sources before sending on to the GUI. In this case, the core needs to validate that the text sent from an ADC hub or client is actually UTF-8; it cannot assume it is UTF-8 just because that is what the protocol expects.

fixing in core indeed makes sense