From 0fbdd907e4b3836b025b8690823c7271f939a938 Mon Sep 17 00:00:00 2001 From: "Wei Hu(Xavier)" Date: Fri, 29 Sep 2017 23:10:12 +0800 Subject: [PATCH] RDMA/hns: Avoid NULL pointer exception [ Upstream commit 5e437b1d7e8d31ff9a4b8e898eb3a6cee309edd9 ] After the loop in hns_roce_v1_mr_free_work_fn function, it is possible that all qps will have been freed (in which case ne will be 0). If that happens, then later in the function when we dereference hr_qp we will get an exception. Check ne is not 0 to make sure we actually have an hr_qp left to work on. This patch fixes the smatch error as below: drivers/infiniband/hw/hns/hns_roce_hw_v1.c:1009 hns_roce_v1_mr_free_work_fn() error: we previously assumed 'hr_qp' could be null Signed-off-by: Wei Hu (Xavier) Signed-off-by: Lijun Ou Signed-off-by: Shaobo Xu Signed-off-by: Doug Ledford Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/hw/hns/hns_roce_hw_v1.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c index 747efd1..8208c30 100644 --- a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c @@ -1001,6 +1001,11 @@ static void hns_roce_v1_mr_free_work_fn(struct work_struct *work) } } + if (!ne) { + dev_err(dev, "Reseved loop qp is absent!\n"); + goto free_work; + } + do { ret = hns_roce_v1_poll_cq(&mr_free_cq->ib_cq, ne, wc); if (ret < 0) { -- 2.7.4