Index: src/applications/diffusion/ssh/DiffusionSSHGitReceivePackWorkflow.php
===================================================================
--- src/applications/diffusion/ssh/DiffusionSSHGitReceivePackWorkflow.php
+++ src/applications/diffusion/ssh/DiffusionSSHGitReceivePackWorkflow.php
@@ -35,6 +35,7 @@
       $repository->writeStatusMessage(
         PhabricatorRepositoryStatusMessage::TYPE_NEEDS_UPDATE,
         PhabricatorRepositoryStatusMessage::CODE_OKAY);
+      $this->waitForGitClient();
     }
 
     return $err;
Index: src/applications/diffusion/ssh/DiffusionSSHGitUploadPackWorkflow.php
===================================================================
--- src/applications/diffusion/ssh/DiffusionSSHGitUploadPackWorkflow.php
+++ src/applications/diffusion/ssh/DiffusionSSHGitUploadPackWorkflow.php
@@ -21,10 +21,16 @@
 
     $future = new ExecFuture('git-upload-pack %s', $repository->getLocalPath());
 
-    return $this->newPassthruCommand()
+    $err = $this->newPassthruCommand()
       ->setIOChannel($this->getIOChannel())
       ->setCommandChannelFromExecFuture($future)
       ->execute();
+
+    if (!$err) {
+      $this->waitForGitClient();
+    }
+
+    return $err;
   }
 
 }
Index: src/applications/diffusion/ssh/DiffusionSSHGitWorkflow.php
===================================================================
--- src/applications/diffusion/ssh/DiffusionSSHGitWorkflow.php
+++ src/applications/diffusion/ssh/DiffusionSSHGitWorkflow.php
@@ -7,4 +7,17 @@
     return parent::writeError($message."\n");
   }
 
+  protected function waitForGitClient() {
+    $io_channel = $this->getIOChannel();
+
+    // If we don't wait for the client to close the connection, `git` will
+    // consider it an early abort and fail. Sit around until Git is comfortable
+    // that it really received all the data.
+    while ($io_channel->isOpenForReading()) {
+      $io_channel->update();
+      $this->getErrorChannel()->flush();
+      PhutilChannel::waitForAny(array($io_channel));
+    }
+  }
+
 }