This is a note to let you know that I've just added the patch titled RDMA/irdma: Prevent some integer underflows to the 5.15-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: rdma-irdma-prevent-some-integer-underflows.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 209c0963da7ddd0df6189b30836685879651afa7 Author: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Date: Mon Mar 7 15:59:28 2022 +0300 RDMA/irdma: Prevent some integer underflows [ Upstream commit 6f6dbb819dfc1a35bcb8b709b5c83a3ea8beff75 ] My static checker complains that: drivers/infiniband/hw/irdma/ctrl.c:3605 irdma_sc_ceq_init() warn: can subtract underflow 'info->dev->hmc_fpm_misc.max_ceqs'? It appears that "info->dev->hmc_fpm_misc.max_ceqs" comes from the firmware in irdma_sc_parse_fpm_query_buf() so, yes, there is a chance that it could be zero. Even if we trust the firmware, it's easy enough to change the condition just as a hardenning measure. Fixes: 3f49d6842569 ("RDMA/irdma: Implement HW Admin Queue OPs") Link: https://lore.kernel.org/r/20220307125928.GE16710@kili Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Acked-by: Shiraz Saleem <shiraz.saleem@xxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/infiniband/hw/irdma/ctrl.c b/drivers/infiniband/hw/irdma/ctrl.c index f1e5515256e0..1ac7067e21be 100644 --- a/drivers/infiniband/hw/irdma/ctrl.c +++ b/drivers/infiniband/hw/irdma/ctrl.c @@ -431,7 +431,7 @@ enum irdma_status_code irdma_sc_qp_create(struct irdma_sc_qp *qp, struct irdma_c cqp = qp->dev->cqp; if (qp->qp_uk.qp_id < cqp->dev->hw_attrs.min_hw_qp_id || - qp->qp_uk.qp_id > (cqp->dev->hmc_info->hmc_obj[IRDMA_HMC_IW_QP].max_cnt - 1)) + qp->qp_uk.qp_id >= (cqp->dev->hmc_info->hmc_obj[IRDMA_HMC_IW_QP].max_cnt)) return IRDMA_ERR_INVALID_QP_ID; wqe = irdma_sc_cqp_get_next_send_wqe(cqp, scratch); @@ -2551,10 +2551,10 @@ static enum irdma_status_code irdma_sc_cq_create(struct irdma_sc_cq *cq, enum irdma_status_code ret_code = 0; cqp = cq->dev->cqp; - if (cq->cq_uk.cq_id > (cqp->dev->hmc_info->hmc_obj[IRDMA_HMC_IW_CQ].max_cnt - 1)) + if (cq->cq_uk.cq_id >= (cqp->dev->hmc_info->hmc_obj[IRDMA_HMC_IW_CQ].max_cnt)) return IRDMA_ERR_INVALID_CQ_ID; - if (cq->ceq_id > (cq->dev->hmc_fpm_misc.max_ceqs - 1)) + if (cq->ceq_id >= (cq->dev->hmc_fpm_misc.max_ceqs)) return IRDMA_ERR_INVALID_CEQ_ID; ceq = cq->dev->ceq[cq->ceq_id]; @@ -3656,7 +3656,7 @@ enum irdma_status_code irdma_sc_ceq_init(struct irdma_sc_ceq *ceq, info->elem_cnt > info->dev->hw_attrs.max_hw_ceq_size) return IRDMA_ERR_INVALID_SIZE; - if (info->ceq_id > (info->dev->hmc_fpm_misc.max_ceqs - 1)) + if (info->ceq_id >= (info->dev->hmc_fpm_misc.max_ceqs)) return IRDMA_ERR_INVALID_CEQ_ID; pble_obj_cnt = info->dev->hmc_info->hmc_obj[IRDMA_HMC_IW_PBLE].cnt; @@ -4205,7 +4205,7 @@ enum irdma_status_code irdma_sc_ccq_init(struct irdma_sc_cq *cq, info->num_elem > info->dev->hw_attrs.uk_attrs.max_hw_cq_size) return IRDMA_ERR_INVALID_SIZE; - if (info->ceq_id > (info->dev->hmc_fpm_misc.max_ceqs - 1)) + if (info->ceq_id >= (info->dev->hmc_fpm_misc.max_ceqs )) return IRDMA_ERR_INVALID_CEQ_ID; pble_obj_cnt = info->dev->hmc_info->hmc_obj[IRDMA_HMC_IW_PBLE].cnt;