From mboxrd@z Thu Jan 1 00:00:00 1970 From: Leon Romanovsky Subject: [PATCH rdma-next 1/6] RDMA/mlx5: Do not allow the user to write to the clock page Date: Tue, 16 Apr 2019 14:07:25 +0300 Message-ID: <20190416110730.32230-2-leon@kernel.org> References: <20190416110730.32230-1-leon@kernel.org> Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: In-Reply-To: <20190416110730.32230-1-leon@kernel.org> Sender: netdev-owner@vger.kernel.org To: Doug Ledford , Jason Gunthorpe Cc: Leon Romanovsky , RDMA mailing list , Andrea Arcangeli , Feras Daoud , Haggai Eran , Jason Gunthorpe , Saeed Mahameed , linux-netdev List-Id: linux-rdma@vger.kernel.org From: Jason Gunthorpe The intent of this VMA was to be read-only from user space, but the VM_MAYWRITE masking was missed, so mprotect could make it writable. Cc: stable@vger.kernel.org Fixes: 5c99eaecb1fc ("IB/mlx5: Mmap the HCA's clock info to user-space") Signed-off-by: Jason Gunthorpe Reviewed-by: Haggai Eran Signed-off-by: Leon Romanovsky --- drivers/infiniband/hw/mlx5/main.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index 15676a149680..73b7f9636f82 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -2072,6 +2072,7 @@ static int mlx5_ib_mmap_clock_info_page(struct mlx5_ib_dev *dev, if (vma->vm_flags & VM_WRITE) return -EPERM; + vma->vm_flags &= ~VM_MAYWRITE; if (!dev->mdev->clock_info_page) return -EOPNOTSUPP; @@ -2237,6 +2238,7 @@ static int mlx5_ib_mmap(struct ib_ucontext *ibcontext, struct vm_area_struct *vm if (vma->vm_flags & VM_WRITE) return -EPERM; + vma->vm_flags &= ~VM_MAYWRITE; /* Don't expose to user-space information it shouldn't have */ if (PAGE_SIZE > 4096) -- 2.20.1