rgw: NULL terminate buffer before parsing it

Fixes: #6175
Backport: dumpling
We get a buffer off the remote gateway which might
not be NULL terminated. The JSON parser needs the
buffer to be NULL terminated even though we provide
a buffer length as it calls strlen().

Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
Signed-off-by: Yehuda Sadeh <yehuda@inktank.com>
(cherry picked from commit e7f7483192cddca1159aba439ce62b1e78669d51)

diff --git a/src/rgw/rgw_rados.cc b/src/rgw/rgw_rados.cc
index d79fbe4c943c233163c60fca8c07037be2a296d3..bada7d22d1b6929d4cfec0e7676e086fa493a646 100644 (file)
--- a/src/rgw/rgw_rados.cc
+++ b/src/rgw/rgw_rados.cc
@@ -2616,6 +2616,7 @@ int RGWRados::copy_obj(void *ctx,
     { /* opening scope so that we can do goto, sorry */
       bufferlist& extra_data_bl = processor.get_extra_data();
       if (extra_data_bl.length()) {
+        extra_data_bl.push_back((char)0);
         JSONParser jp;
         if (!jp.parse(extra_data_bl.c_str(), extra_data_bl.length())) {
           ldout(cct, 0) << "failed to parse response extra data. len=" << extra_data_bl.length() << " data=" << extra_data_bl.c_str() << dendl;