From c803c3963cfe791eff1a82c10972002a09c57f93 Mon Sep 17 00:00:00 2001
From: Dietmar Maurer <dietmar@proxmox.com>
Date: Thu, 31 Jan 2013 11:52:31 +0100
Subject: [PATCH] use chattr to set immutable flag on base images

---
 PVE/Storage/Plugin.pm | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/PVE/Storage/Plugin.pm b/PVE/Storage/Plugin.pm
index 0cbf488..9545626 100644
--- a/PVE/Storage/Plugin.pm
+++ b/PVE/Storage/Plugin.pm
@@ -449,8 +449,14 @@ sub create_base {
     rename($path, $newpath) || 
 	die "rename '$path' to '$newpath' failed - $!\n";
 
-    chmod(0444, $newpath);
+    # We try to protect base volume
 
+    chmod(0444, $newpath); # nobody should write anything
+
+    # also try to set immutable flag
+    eval { run_command(['/usr/bin/chattr', '+i', $newpath]); };
+    warn $@ if $@;
+    
     return $newvolname;
 }
 
@@ -575,9 +581,13 @@ sub free_image {
 		    "(use by '$tmpvolname')\n";
 	    }
 	}
+ 
+	# try to remove immutable flag
+	eval { run_command(['/usr/bin/chattr', '-i', $path]); };
+	warn $@ if $@;
     }
 
-    unlink $path;
+    unlink($path) || die "unlink '$path' failed - $!\n";
 
     return undef;
 }
-- 
2.39.2