From: david-sarah <david-sarah@jacaranda.org>
Date: Sun, 23 May 2010 23:38:30 +0000 (-0700)
Subject: SFTP: avoid race condition where .write could be called on an OverwriteableFileConsum... 
X-Git-Tag: trac-4400~8
X-Git-Url: https://git.rkrishnan.org/%5B/%5D%20/uri/frontends/FTP-and-SFTP.rst?a=commitdiff_plain;h=6e114e44b543e29423f86408e5acdfbf7813c14e;p=tahoe-lafs%2Ftahoe-lafs.git

SFTP: avoid race condition where .write could be called on an OverwriteableFileConsumer after it had been closed.
---

diff --git a/src/allmydata/frontends/sftpd.py b/src/allmydata/frontends/sftpd.py
index d1265de6..819191a8 100644
--- a/src/allmydata/frontends/sftpd.py
+++ b/src/allmydata/frontends/sftpd.py
@@ -336,6 +336,7 @@ class OverwriteableFileConsumer(PrefixingLogMixin):
         self.downloaded = 0
         self.milestones = []  # empty heap of (offset, d)
         self.overwrites = []  # empty heap of (start, end)
+        self.is_closed = False
         self.done = self.when_reached(download_size)  # adds a milestone
         self.is_done = False
         def _signal_done(ign):
@@ -376,6 +377,8 @@ class OverwriteableFileConsumer(PrefixingLogMixin):
 
     def write(self, data):
         if noisy: self.log(".write(<data of length %r>)" % (len(data),), level=NOISY)
+        if self.is_closed:
+            return
         if self.check_abort():
             self.close()
             return
@@ -520,6 +523,7 @@ class OverwriteableFileConsumer(PrefixingLogMixin):
         #self.unregisterProducer()
 
     def close(self):
+        self.is_closed = True
         self.finish()
         self.f.close()