From: Noa Osherovich Date: Sat, 4 Jun 2016 12:15:31 +0000 (+0300) Subject: IB/mlx5: Limit query HCA clock X-Git-Tag: v4.7-rc3~25^2~7 X-Git-Url: http://git.cascardo.info/?p=cascardo%2Flinux.git;a=commitdiff_plain;h=bc5c6eed0510f19b033ce7a7d3976e695e96785b IB/mlx5: Limit query HCA clock When PAGE_SIZE is larger than 4K, the user shouldn't be able to query the HCA core clock. This counter is within 4KB boundary and the user-space shall not read information that's after this boundary. Fixes: b368d7cb8ceb7 ('IB/mlx5: Add hca_core_clock_offset to...') Signed-off-by: Majd Dibbiny Signed-off-by: Noa Osherovich Signed-off-by: Leon Romanovsky Signed-off-by: Doug Ledford --- diff --git a/drivers/infiniband/hw/mlx5/main.c b/drivers/infiniband/hw/mlx5/main.c index 8845f4b9621b..05036dbb9804 100644 --- a/drivers/infiniband/hw/mlx5/main.c +++ b/drivers/infiniband/hw/mlx5/main.c @@ -991,7 +991,14 @@ static struct ib_ucontext *mlx5_ib_alloc_ucontext(struct ib_device *ibdev, if (field_avail(typeof(resp), cqe_version, udata->outlen)) resp.response_length += sizeof(resp.cqe_version); - if (field_avail(typeof(resp), hca_core_clock_offset, udata->outlen)) { + /* + * We don't want to expose information from the PCI bar that is located + * after 4096 bytes, so if the arch only supports larger pages, let's + * pretend we don't support reading the HCA's core clock. This is also + * forced by mmap function. + */ + if (PAGE_SIZE <= 4096 && + field_avail(typeof(resp), hca_core_clock_offset, udata->outlen)) { resp.comp_mask |= MLX5_IB_ALLOC_UCONTEXT_RESP_MASK_CORE_CLOCK_OFFSET; resp.hca_core_clock_offset =