Add a check to ensure that all shift counts are valid.
Shifting by more than 63 bits may result in undefined behavior, as
noted during coverity scan.
Fixes: e697f35dbdd1 ("event/dlb2: update rolling mask used for dequeue")
Coverity issue: 376527
Signed-off-by: Timothy McDaniel <timothy.mcdan...@intel.com>
---
drivers/event/dlb2/dlb2.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/drivers/event/dlb2/dlb2.c b/drivers/event/dlb2/dlb2.c
index 09abdd1660..7789dd74e0 100644
--- a/drivers/event/dlb2/dlb2.c
+++ b/drivers/event/dlb2/dlb2.c
@@ -3916,15 +3916,17 @@ dlb2_hw_dequeue_sparse(struct dlb2_eventdev *dlb2,
&events[num],
&qes[0],
num_avail);
- num += n_iter;
- /* update rolling_mask for vector code support */
- m_rshift = qm_port->cq_rolling_mask >> n_iter;
- m_lshift = qm_port->cq_rolling_mask << (64 - n_iter);
- m2_rshift = qm_port->cq_rolling_mask_2 >> n_iter;
- m2_lshift = qm_port->cq_rolling_mask_2 <<
+ if (n_iter != 0) {
+ num += n_iter;
+ /* update rolling_mask for vector code support
*/
+ m_rshift = qm_port->cq_rolling_mask >> n_iter;
+ m_lshift = qm_port->cq_rolling_mask << (64 -
n_iter);
+ m2_rshift = qm_port->cq_rolling_mask_2 >>
n_iter;
+ m2_lshift = qm_port->cq_rolling_mask_2 <<
(64 - n_iter);
- qm_port->cq_rolling_mask = (m_rshift | m2_lshift);
- qm_port->cq_rolling_mask_2 = (m2_rshift | m_lshift);
+ qm_port->cq_rolling_mask = (m_rshift |
m2_lshift);
+ qm_port->cq_rolling_mask_2 = (m2_rshift |
m_lshift);
+ }
} else { /* !use_scalar */
num_avail = dlb2_recv_qe_sparse_vec(qm_port,
&events[num],
--
2.25.1
