This is a note to let you know that I've just added the patch titled RDMA/hns: Fix UAF for cq async event to the 6.1-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-hns-fix-uaf-for-cq-async-event.patch and it can be found in the queue-6.1 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 508fd8f223f2e84531fb6fe70ccf86517f9ea092 Author: Chengchang Tang <tangchengchang@xxxxxxxxxx> Date: Fri Apr 12 17:16:11 2024 +0800 RDMA/hns: Fix UAF for cq async event [ Upstream commit a942ec2745ca864cd8512142100e4027dc306a42 ] The refcount of CQ is not protected by locks. When CQ asynchronous events and CQ destruction are concurrent, CQ may have been released, which will cause UAF. Use the xa_lock() to protect the CQ refcount. Fixes: 9a4435375cd1 ("IB/hns: Add driver files for hns RoCE driver") Signed-off-by: Chengchang Tang <tangchengchang@xxxxxxxxxx> Signed-off-by: Junxian Huang <huangjunxian6@xxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240412091616.370789-6-huangjunxian6@xxxxxxxxxxxxx Signed-off-by: Leon Romanovsky <leon@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/infiniband/hw/hns/hns_roce_cq.c b/drivers/infiniband/hw/hns/hns_roce_cq.c index 736dc2f993b40..ff177466de9b4 100644 --- a/drivers/infiniband/hw/hns/hns_roce_cq.c +++ b/drivers/infiniband/hw/hns/hns_roce_cq.c @@ -151,7 +151,7 @@ static int alloc_cqc(struct hns_roce_dev *hr_dev, struct hns_roce_cq *hr_cq) return ret; } - ret = xa_err(xa_store(&cq_table->array, hr_cq->cqn, hr_cq, GFP_KERNEL)); + ret = xa_err(xa_store_irq(&cq_table->array, hr_cq->cqn, hr_cq, GFP_KERNEL)); if (ret) { ibdev_err(ibdev, "failed to xa_store CQ, ret = %d.\n", ret); goto err_put; @@ -164,7 +164,7 @@ static int alloc_cqc(struct hns_roce_dev *hr_dev, struct hns_roce_cq *hr_cq) return 0; err_xa: - xa_erase(&cq_table->array, hr_cq->cqn); + xa_erase_irq(&cq_table->array, hr_cq->cqn); err_put: hns_roce_table_put(hr_dev, &cq_table->table, hr_cq->cqn); @@ -183,7 +183,7 @@ static void free_cqc(struct hns_roce_dev *hr_dev, struct hns_roce_cq *hr_cq) dev_err(dev, "DESTROY_CQ failed (%d) for CQN %06lx\n", ret, hr_cq->cqn); - xa_erase(&cq_table->array, hr_cq->cqn); + xa_erase_irq(&cq_table->array, hr_cq->cqn); /* Waiting interrupt process procedure carried out */ synchronize_irq(hr_dev->eq_table.eq[hr_cq->vector].irq); @@ -472,13 +472,6 @@ void hns_roce_cq_event(struct hns_roce_dev *hr_dev, u32 cqn, int event_type) struct ib_event event; struct ib_cq *ibcq; - hr_cq = xa_load(&hr_dev->cq_table.array, - cqn & (hr_dev->caps.num_cqs - 1)); - if (!hr_cq) { - dev_warn(dev, "async event for bogus CQ 0x%06x\n", cqn); - return; - } - if (event_type != HNS_ROCE_EVENT_TYPE_CQ_ID_INVALID && event_type != HNS_ROCE_EVENT_TYPE_CQ_ACCESS_ERROR && event_type != HNS_ROCE_EVENT_TYPE_CQ_OVERFLOW) { @@ -487,7 +480,16 @@ void hns_roce_cq_event(struct hns_roce_dev *hr_dev, u32 cqn, int event_type) return; } - refcount_inc(&hr_cq->refcount); + xa_lock(&hr_dev->cq_table.array); + hr_cq = xa_load(&hr_dev->cq_table.array, + cqn & (hr_dev->caps.num_cqs - 1)); + if (hr_cq) + refcount_inc(&hr_cq->refcount); + xa_unlock(&hr_dev->cq_table.array); + if (!hr_cq) { + dev_warn(dev, "async event for bogus CQ 0x%06x\n", cqn); + return; + } ibcq = &hr_cq->ib_cq; if (ibcq->event_handler) {