From: Graeme Fowler <graemef@exim.org>
Date: Tue, 17 Nov 2015 14:01:28 +0000 (+0000)
Subject: GF: Fix esoteric race condition in exicyclog
X-Git-Tag: exim-4_87_RC1~44
X-Git-Url: https://git.exim.org/exim.git/commitdiff_plain/77d31cea07808daf55f04cf6929adf5d805fa726

GF: Fix esoteric race condition in exicyclog
---

diff --git a/src/src/exicyclog.src b/src/src/exicyclog.src
index 01d1f2feb..1559a4794 100644
--- a/src/src/exicyclog.src
+++ b/src/src/exicyclog.src
@@ -282,28 +282,34 @@ done
 
 if [ $keep -gt 99 ]; then first=001; else first=01; fi
 
+# Grab our pid ro avoid race in file creation
+ourpid=$$
+
 if [ -f $mainlog ]; then
   $mv $mainlog $mainlog.$first
   $chown $user:$group $mainlog.$first
-  $touch $mainlog
-  $chown $user:$group $mainlog
-  $chmod 640 $mainlog
+  $touch $mainlog.$ourpid
+  $chown $user:$group $mainlog.$ourpid
+  $chmod 640 $mainlog.$ourpid
+  $mv $mainlog.$ourpid $mainlog
 fi
 
 if [ -f $rejectlog ]; then
   $mv $rejectlog $rejectlog.$first
   $chown $user:$group $rejectlog.$first
-  $touch $rejectlog
-  $chown $user:$group $rejectlog
-  $chmod 640 $rejectlog
+  $touch $rejectlog.$ourpid
+  $chown $user:$group $rejectlog.$ourpid
+  $chmod 640 $rejectlog.$ourpid
+  $mv $rejectlog.$ourpid $rejectlog
 fi
 
 if [ -f $paniclog ]; then
   $mv $paniclog $paniclog.$first
   $chown $user:$group $paniclog.$first
-  $touch $paniclog
-  $chown $user:$group $paniclog
-  $chmod 640 $paniclog
+  $touch $paniclog.$ourpid
+  $chown $user:$group $paniclog.$ourpid
+  $chmod 640 $paniclog.$ourpid
+  $mv $paniclog.$ourpid $paniclog
 fi
 
 # Now scan the (0)02 and later files, compressing where necessary, and