This is a note to let you know that I've just added the patch titled RDMA/hns: Avoid NULL pointer exception to the 4.14-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-avoid-null-pointer-exception.patch and it can be found in the queue-4.14 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Wed Dec 20 18:17:52 CET 2017 From: "Wei Hu(Xavier)" <xavier.huwei@xxxxxxxxxx> Date: Fri, 29 Sep 2017 23:10:12 +0800 Subject: RDMA/hns: Avoid NULL pointer exception From: "Wei Hu(Xavier)" <xavier.huwei@xxxxxxxxxx> [ 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) <xavier.huwei@xxxxxxxxxx> Signed-off-by: Lijun Ou <oulijun@xxxxxxxxxx> Signed-off-by: Shaobo Xu <xushaobo2@xxxxxxxxxx> Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/infiniband/hw/hns/hns_roce_hw_v1.c | 5 +++++ 1 file changed, 5 insertions(+) --- 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( } } + 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) { Patches currently in stable-queue which might be from xavier.huwei@xxxxxxxxxx are queue-4.14/rdma-hns-avoid-null-pointer-exception.patch