From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yann Droneaud Subject: [PATCH v1 2/5] IB/uverbs: ex_query_device: check request's comp_mask Date: Thu, 29 Jan 2015 18:59:59 +0100 Message-ID: <335da45738872e446f63db338ca766a34608c90a.1422553023.git.ydroneaud@opteya.com> References: Return-path: In-Reply-To: In-Reply-To: References: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sagi Grimberg , Shachar Raindel , Eli Cohen , Haggai Eran , Roland Dreier Cc: Yann Droneaud , linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-api-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: linux-rdma@vger.kernel.org This patch ensures the extended QUERY_DEVICE uverbs request's comp_mask has only known and supported bits (currently none). If userspace set unknown features bits, -EINVAL will be returned, ensuring current programs are not allowed to set random feature bits: such bits could enable new extended features in future kernel versions and those features can trigger a behavior not unsupported by the older programs or make the newer kernels return an error for a request which was valid on older kernels. Additionally, returning an error for unsupported feature would allow userspace to probe/discover which extended features are currently supported by a kernel. Link: http://mid.gmane.org/cover.1422553023.git.ydroneaud-RlY5vtjFyJ3QT0dZR+AlfA@public.gmane.org Cc: Sagi Grimberg Cc: Shachar Raindel Cc: Eli Cohen Cc: Haggai Eran Signed-off-by: Yann Droneaud --- drivers/infiniband/core/uverbs_cmd.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/infiniband/core/uverbs_cmd.c b/drivers/infiniband/core/uverbs_cmd.c index 6ef06a9b4362..fbcc54b86795 100644 --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -3312,6 +3312,9 @@ int ib_uverbs_ex_query_device(struct ib_uverbs_file *file, if (err) return err; + if (cmd.comp_mask) + return -EINVAL; + if (cmd.reserved) return -EINVAL; -- 2.1.0 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html