RDMA/mlx5: Fix multiple NULL-ptr deref errors in rereg_mr flow
authorLeon Romanovsky <leonro@mellanox.com>
Mon, 23 Apr 2018 14:01:52 +0000 (17:01 +0300)
committerDoug Ledford <dledford@redhat.com>
Fri, 27 Apr 2018 15:03:15 +0000 (11:03 -0400)
commitb4bd701ac469075d94ed9699a28755f2862252b9
treebbcf8bcc82f8834189da42cd1406dfa7d3e810f3
parentdc5640f294e4ff6b89047cb4a0dfa931d5f0cd1f
RDMA/mlx5: Fix multiple NULL-ptr deref errors in rereg_mr flow

Failure in rereg MR releases UMEM but leaves the MR to be destroyed
by the user. As a result the following scenario may happen:
"create MR -> rereg MR with failure -> call to rereg MR again" and
hit "NULL-ptr deref or user memory access" errors.

Ensure that rereg MR is only performed on a non-dead MR.

Cc: syzkaller <syzkaller@googlegroups.com>
Cc: <stable@vger.kernel.org> # 4.5
Fixes: 395a8e4c32ea ("IB/mlx5: Refactoring register MR code")
Reported-by: Noa Osherovich <noaos@mellanox.com>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Doug Ledford <dledford@redhat.com>
drivers/infiniband/hw/mlx5/mr.c