From 91f639c74e0bbf28c4b06be2dc73f96bf51b568a Mon Sep 17 00:00:00 2001
From: n0p <0x90@n0p.cc>
Date: Sat, 18 Feb 2017 23:40:01 +0100
Subject: Basic blocks without an entry, e.g., exception handler basic blocks
 in IDA, containing a system call are supported, now.

---
 idaSystemCalls.py | 31 ++++++++++++++++++++++++-------
 1 file changed, 24 insertions(+), 7 deletions(-)

diff --git a/idaSystemCalls.py b/idaSystemCalls.py
index 3bd9258..88bb374 100644
--- a/idaSystemCalls.py
+++ b/idaSystemCalls.py
@@ -882,6 +882,8 @@ class SystemCall():
     def getSystemCallNumber(self, addr):
         """ Get the value of rax/eax at the time of the system call.
         """
+
+        sol = list()
  
         # Init
         machine = guess_machine()
@@ -898,12 +900,30 @@ class SystemCall():
             mdis.symbol_pool.add_label(name, ad)
  
         # Get the current function
-        func = idaapi.get_func(addr)
-        blocs = mdis.dis_multibloc(func.startEA)
- 
+        f = get_func(addr)
+
+        if not f:
+            return sol
+
+        blocs = mdis.dis_multibloc(f.startEA)
+
         # Generate IR
         for bloc in blocs:
             ir_arch.add_bloc(bloc)
+
+        # Check if addr is in a basic block without an entry.
+        if len(ir_arch.getby_offset(addr)) == 0:
+            fc = qflow_chart_t("", f, BADADDR, BADADDR, FC_PREDS)
+
+            # Iterate through all basic blocks.
+            for i in xrange(0, fc.size()):
+                if fc[i].startEA <= addr and addr < fc[i].endEA:
+                    # Basic block without entry found.
+                    blocs = mdis.dis_multibloc(fc[i].startEA)
+
+                    # Generate IR
+                    for bloc in blocs:
+                        ir_arch.add_bloc(bloc)
  
         cur_bloc = list(ir_arch.getby_offset(addr))[0]
         cur_label = cur_bloc.label
@@ -917,10 +937,7 @@ class SystemCall():
         # Get dependency graphs
         dg = DependencyGraph(ir_arch, follow_call=False)
         graphs = dg.get(cur_label, elements, line_nb,
-                        set([ir_arch.symbol_pool.getby_offset(func.startEA)]))
- 
-        # Display the result
-        sol = list()
+                        set([ir_arch.symbol_pool.getby_offset(f.startEA)]))
  
         while 1:
             try:
-- 
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