From: Wei Hu(Xavier) Date: Fri, 29 Sep 2017 15:10:12 +0000 (+0800) Subject: RDMA/hns: Avoid NULL pointer exception X-Git-Tag: v4.15-rc1~96^2~111^2~79 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5e437b1d7e8d31ff9a4b8e898eb3a6cee309edd9;p=thirdparty%2Fkernel%2Flinux.git RDMA/hns: Avoid NULL pointer exception 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 --- diff --git a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c index 98887dd8ccb35..852db18ec128b 100644 --- a/drivers/infiniband/hw/hns/hns_roce_hw_v1.c +++ b/drivers/infiniband/hw/hns/hns_roce_hw_v1.c @@ -1004,6 +1004,11 @@ 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) {