extras/try_gzip_static: do not show backtrace on syscall errors

On ENAMETOOLONG and perhaps other system errors which we can do
nothing about, we should not spew a giant backtrace which could
be used as an easy DoS vector.

1 files changed, 1 insertions, 1 deletions

diff --git a/extras/try_gzip_static.rb b/extras/try_gzip_static.rb
index 0d5d63b..31c1aa1 100644
--- a/extras/try_gzip_static.rb
+++ b/extras/try_gzip_static.rb
@@ -203,7 +203,7 @@ class TryGzipStatic
       msg = msg.dump if /[[:cntrl:]]/ =~ msg # prevent code injection
       logger.warn("#{env['REQUEST_METHOD']} #{env['PATH_INFO']} " \
                   "#{code} #{msg}")
-      if exc.respond_to?(:backtrace)
+      if exc.respond_to?(:backtrace) && !(SystemCallError === exc)
         exc.backtrace.each { |line| logger.warn(line) }
       end
     end