This is a note to let you know that I've just added the patch titled net: thunderx: Fix unintentional sign extension issue to the 4.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: net-thunderx-fix-unintentional-sign-extension-issue.patch and it can be found in the queue-4.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c748d64697d9aec71bcf71d1013c3fb82385d8c0 Author: Colin Ian King <colin.king@xxxxxxxxxxxxx> Date: Fri Apr 9 14:07:26 2021 +0100 net: thunderx: Fix unintentional sign extension issue [ Upstream commit e701a25840360706fe4cf5de0015913ca19c274b ] The shifting of the u8 integers rq->caching by 26 bits to the left will be promoted to a 32 bit signed int and then sign-extended to a u64. In the event that rq->caching is greater than 0x1f then all then all the upper 32 bits of the u64 end up as also being set because of the int sign-extension. Fix this by casting the u8 values to a u64 before the 26 bit left shift. Addresses-Coverity: ("Unintended sign extension") Fixes: 4863dea3fab0 ("net: Adding support for Cavium ThunderX network controller") Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c index 912ee28ab58b..5da49e8b533b 100644 --- a/drivers/net/ethernet/cavium/thunder/nicvf_queues.c +++ b/drivers/net/ethernet/cavium/thunder/nicvf_queues.c @@ -528,7 +528,7 @@ static void nicvf_rcv_queue_config(struct nicvf *nic, struct queue_set *qs, mbx.rq.msg = NIC_MBOX_MSG_RQ_CFG; mbx.rq.qs_num = qs->vnic_id; mbx.rq.rq_num = qidx; - mbx.rq.cfg = (rq->caching << 26) | (rq->cq_qs << 19) | + mbx.rq.cfg = ((u64)rq->caching << 26) | (rq->cq_qs << 19) | (rq->cq_idx << 16) | (rq->cont_rbdr_qs << 9) | (rq->cont_qs_rbdr_idx << 8) | (rq->start_rbdr_qs << 1) | (rq->start_qs_rbdr_idx);