qr_content_extract used dict_get to get the value of the GF_CONTENT_KEY key. dict_get does not ref the data before returning it so QR could be acting on freed memory if another thread deletes the key before then. This patch also fixes a race in dict_get_with_ref. Fix: Use dict_get_with_ref to retrieve the file contents. Change-Id: Ib1a7a70bb92eed7e70747ec530e0b3edc53127ec BUG: 1484709 Signed-off-by: N Balachandran <nbalacha@redhat.com> Reviewed-on: https://review.gluster.org/18115 Smoke: Gluster Build System <jenkins@build.gluster.org> Reviewed-by: Amar Tumballi <amarts@redhat.com> Tested-by: Raghavendra G <rgowdapp@redhat.com> CentOS-regression: Gluster Build System <jenkins@build.gluster.org> Reviewed-by: Raghavendra G <rgowdapp@redhat.com>