From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.linuxfoundation.org ([140.211.169.12]:45366 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933345AbeCWKOq (ORCPT ); Fri, 23 Mar 2018 06:14:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Vlad Tsyrklevich , Doug Ledford , Sasha Levin Subject: [PATCH 4.4 44/97] infiniband/uverbs: Fix integer overflows Date: Fri, 23 Mar 2018 10:54:31 +0100 Message-Id: <20180323094200.109336079@linuxfoundation.org> In-Reply-To: <20180323094157.535925724@linuxfoundation.org> References: <20180323094157.535925724@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Vlad Tsyrklevich [ Upstream commit 4f7f4dcfff2c19debbcdbcc861c325610a15e0c5 ] The 'num_sge' variable is verfied to be smaller than the 'sge_count' variable; however, since both are user-controlled it's possible to cause an integer overflow for the kmalloc multiply on 32-bit platforms (num_sge and sge_count are both defined u32). By crafting an input that causes a smaller-than-expected allocation it's possible to write controlled data out-of-bounds. Signed-off-by: Vlad Tsyrklevich Signed-off-by: Doug Ledford Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/core/uverbs_cmd.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) --- a/drivers/infiniband/core/uverbs_cmd.c +++ b/drivers/infiniband/core/uverbs_cmd.c @@ -2436,9 +2436,13 @@ ssize_t ib_uverbs_destroy_qp(struct ib_u static void *alloc_wr(size_t wr_size, __u32 num_sge) { + if (num_sge >= (U32_MAX - ALIGN(wr_size, sizeof (struct ib_sge))) / + sizeof (struct ib_sge)) + return NULL; + return kmalloc(ALIGN(wr_size, sizeof (struct ib_sge)) + num_sge * sizeof (struct ib_sge), GFP_KERNEL); -}; +} ssize_t ib_uverbs_post_send(struct ib_uverbs_file *file, struct ib_device *ib_dev, @@ -2664,6 +2668,13 @@ static struct ib_recv_wr *ib_uverbs_unma ret = -EINVAL; goto err; } + + if (user_wr->num_sge >= + (U32_MAX - ALIGN(sizeof *next, sizeof (struct ib_sge))) / + sizeof (struct ib_sge)) { + ret = -EINVAL; + goto err; + } next = kmalloc(ALIGN(sizeof *next, sizeof (struct ib_sge)) + user_wr->num_sge * sizeof (struct ib_sge),