From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755422AbbHBAmx (ORCPT ); Sat, 1 Aug 2015 20:42:53 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36694 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752737AbbHBAaN (ORCPT ); Sat, 1 Aug 2015 20:30:13 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Jack Morgenstein" , "Shachar Raindel" , "Doug Ledford" , "Yann Droneaud" , "Or Gerlitz" Date: Sun, 02 Aug 2015 01:02:37 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 043/164] IB/core: disallow registering 0-sized memory region In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.249 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.70-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Yann Droneaud commit 8abaae62f3fdead8f4ce0ab46b4ab93dee39bab2 upstream. If ib_umem_get() is called with a size equal to 0 and an non-page aligned address, one page will be pinned and a 0-sized umem will be returned to the caller. This should not be allowed: it's not expected for a memory region to have a size equal to 0. This patch adds a check to explicitly refuse to register a 0-sized region. Link: http://mid.gmane.org/cover.1428929103.git.ydroneaud@opteya.com Cc: Shachar Raindel Cc: Jack Morgenstein Cc: Or Gerlitz Signed-off-by: Yann Droneaud Signed-off-by: Doug Ledford Signed-off-by: Ben Hutchings --- drivers/infiniband/core/umem.c | 3 +++ 1 file changed, 3 insertions(+) --- a/drivers/infiniband/core/umem.c +++ b/drivers/infiniband/core/umem.c @@ -94,6 +94,9 @@ struct ib_umem *ib_umem_get(struct ib_uc if (dmasync) dma_set_attr(DMA_ATTR_WRITE_BARRIER, &attrs); + if (!size) + return ERR_PTR(-EINVAL); + /* * If the combination of the addr and size requested for this memory * region causes an integer overflow, return error.