Re: [PATCH rdma-rc] RDMA/mlx4: Map core_clock page to user space only when allowed

On Thu, Jun 03, 2021 at 04:19:39PM +0300, Leon Romanovsky wrote:

From: Shay Drory <redacted>

Currently when we map the hca_core_clock page to the user space,
there are vulnerable registers, one of which is semaphore, on
this page as well. If user read the wrong offset, it can modify the
above semaphore and hang the device.

Hence, mapping the hca_core_clock page to the user space only when
user required it specifically.

After this patch, mlx4 core_clock won't be mapped to user space by
default. Oppose to current state, where mlx4 core_clock is always mapped
to user space.

Fixes: 52033cfb5aab ("IB/mlx4: Add mmap call to map the hardware clock")
Signed-off-by: Shay Drory <redacted>
Signed-off-by: Leon Romanovsky <leonro@nvidia.com>
---
 drivers/infiniband/hw/mlx4/main.c         | 5 +----
 drivers/net/ethernet/mellanox/mlx4/fw.c   | 3 +++
 drivers/net/ethernet/mellanox/mlx4/fw.h   | 1 +
 drivers/net/ethernet/mellanox/mlx4/main.c | 6 ++++++
 include/linux/mlx4/device.h               | 1 +
 5 files changed, 12 insertions(+), 4 deletions(-)

Applied to for-rc, thanks

Jason