releases/4.14.33/rdma-ucma-check-that-device-exists-prior-to-accessing-it.patch

   1 From c8d3bcbfc5eab3f01cf373d039af725f3b488813 Mon Sep 17 00:00:00 2001
   2 From: Leon Romanovsky <leonro@mellanox.com>
   3 Date: Sun, 25 Mar 2018 11:39:05 +0300
   4 Subject: RDMA/ucma: Check that device exists prior to accessing it
   5
   6 From: Leon Romanovsky <leonro@mellanox.com>
   7
   8 commit c8d3bcbfc5eab3f01cf373d039af725f3b488813 upstream.
   9
  10 Ensure that device exists prior to accessing its properties.
  11
  12 Reported-by: <syzbot+71655d44855ac3e76366@syzkaller.appspotmail.com>
  13 Fixes: 75216638572f ("RDMA/cma: Export rdma cm interface to userspace")
  14 Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
  15 Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
  16 Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
  17
  18 ---
  19  drivers/infiniband/core/ucma.c |    6 ++++--
  20  1 file changed, 4 insertions(+), 2 deletions(-)
  21
  22 --- a/drivers/infiniband/core/ucma.c
  23 +++ b/drivers/infiniband/core/ucma.c
  24 @@ -1335,7 +1335,7 @@ static ssize_t ucma_notify(struct ucma_f
  25  {
  26         struct rdma_ucm_notify cmd;
  27         struct ucma_context *ctx;
  28 -       int ret;
  29 +       int ret = -EINVAL;
  30
  31         if (copy_from_user(&cmd, inbuf, sizeof(cmd)))
  32                 return -EFAULT;
  33 @@ -1344,7 +1344,9 @@ static ssize_t ucma_notify(struct ucma_f
  34         if (IS_ERR(ctx))
  35                 return PTR_ERR(ctx);
  36
  37 -       ret = rdma_notify(ctx->cm_id, (enum ib_event_type) cmd.event);
  38 +       if (ctx->cm_id->device)
  39 +               ret = rdma_notify(ctx->cm_id, (enum ib_event_type)cmd.event);
  40 +
  41         ucma_put_ctx(ctx);
  42         return ret;
  43  }