releases/4.16.4/rdma-ucma-don-t-allow-setting-rdma_option_ib_path-without-an-rdma-device.patch

   1 From 8435168d50e66fa5eae01852769d20a36f9e5e83 Mon Sep 17 00:00:00 2001
   2 From: Roland Dreier <roland@purestorage.com>
   3 Date: Tue, 3 Apr 2018 15:33:01 -0700
   4 Subject: RDMA/ucma: Don't allow setting RDMA_OPTION_IB_PATH without an RDMA device
   5
   6 From: Roland Dreier <roland@purestorage.com>
   7
   8 commit 8435168d50e66fa5eae01852769d20a36f9e5e83 upstream.
   9
  10 Check to make sure that ctx->cm_id->device is set before we use it.
  11 Otherwise userspace can trigger a NULL dereference by doing
  12 RDMA_USER_CM_CMD_SET_OPTION on an ID that is not bound to a device.
  13
  14 Cc: <stable@vger.kernel.org>
  15 Reported-by: <syzbot+a67bc93e14682d92fc2f@syzkaller.appspotmail.com>
  16 Signed-off-by: Roland Dreier <roland@purestorage.com>
  17 Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
  18 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  19
  20 ---
  21  drivers/infiniband/core/ucma.c |    3 +++
  22  1 file changed, 3 insertions(+)
  23
  24 --- a/drivers/infiniband/core/ucma.c
  25 +++ b/drivers/infiniband/core/ucma.c
  26 @@ -1241,6 +1241,9 @@ static int ucma_set_ib_path(struct ucma_
  27         if (!optlen)
  28                 return -EINVAL;
  29
  30 +       if (!ctx->cm_id->device)
  31 +               return -EINVAL;
  32 +
  33         memset(&sa_path, 0, sizeof(sa_path));
  34
  35         sa_path.rec_type = SA_PATH_REC_TYPE_IB;