From 22bfedf8bbea3a9aa25d64928c05129292893f23 Mon Sep 17 00:00:00 2001
From: Mark Mossberg <mark.mossberg@gmail.com>
Date: Wed, 7 Jun 2017 17:22:37 -0400
Subject: [PATCH] Fix signal_transmit crash (#286)

* Check if fd is in self.rwait

* Check if set is empty
---
 manticore/platforms/linux.py | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/manticore/platforms/linux.py b/manticore/platforms/linux.py
index dd3aaaa..c0f4223 100644
--- a/manticore/platforms/linux.py
+++ b/manticore/platforms/linux.py
@@ -1590,9 +1590,13 @@ class Linux(Platform):
 
     def signal_transmit(self, fd):
         ''' Awake one process waiting to transmit data on fd '''
-        connections = self.connections
-        if connections(fd) and self.rwait[connections(fd)]:
-            procid = random.sample(self.rwait[connections(fd)], 1)[0]
+        connection = self.connections(fd)
+        if connection is None or connection >= len(self.rwait):
+            return
+
+        procs = self.rwait[connection]
+        if procs:
+            procid = random.sample(procs, 1)[0]
             self.awake(procid)
 
     def check_timers(self):