From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751619AbeAaF3y (ORCPT ); Wed, 31 Jan 2018 00:29:54 -0500 Received: from gateway32.websitewelcome.com ([192.185.144.98]:15087 "EHLO gateway32.websitewelcome.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751163AbeAaF3w (ORCPT ); Wed, 31 Jan 2018 00:29:52 -0500 Date: Tue, 30 Jan 2018 23:29:48 -0600 From: "Gustavo A. R. Silva" To: Ilya Dryomov , "Yan, Zheng" , Sage Weil , "David S. Miller" Cc: ceph-devel@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" Subject: [PATCH] libceph: use 64-bit arithmetic instead of 32-bit Message-ID: <20180131052948.GA16419@embeddedgus> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.24 (2015-08-30) X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - gator4166.hostgator.com X-AntiAbuse: Original Domain - vger.kernel.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - embeddedor.com X-BWhitelist: no X-Source-IP: 189.152.201.65 X-Source-L: No X-Exim-ID: 1egkxz-002zhY-J3 X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: (embeddedgus) [189.152.201.65]:56046 X-Source-Auth: gustavo@embeddedor.com X-Email-Count: 7 X-Source-Cap: Z3V6aWRpbmU7Z3V6aWRpbmU7Z2F0b3I0MTY2Lmhvc3RnYXRvci5jb20= X-Local-Domain: yes Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Cast objsetno to u64 in order to give the compiler complete information about the proper arithmetic to use. Notice that this variable is used in a context that expects an expression of type u64 (64 bits, unsigned). The expression objsetno * sc + stripepos is currently being evaluated using 32-bit arithmetic. In general, the use of incorrect arithmetic has security implications. Addresses-Coverity-ID: 200686 Signed-off-by: Gustavo A. R. Silva --- net/ceph/osdmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/ceph/osdmap.c b/net/ceph/osdmap.c index 0da27c6..58dc965 100644 --- a/net/ceph/osdmap.c +++ b/net/ceph/osdmap.c @@ -2183,7 +2183,7 @@ int ceph_calc_file_object_mapping(struct ceph_file_layout *layout, stripepos = bl % sc; objsetno = stripeno / su_per_object; - *ono = objsetno * sc + stripepos; + *ono = (u64)objsetno * sc + stripepos; dout("objset %u * sc %u = ono %u\n", objsetno, sc, (unsigned int)*ono); /* *oxoff = *off % layout->fl_stripe_unit; # offset in su */ -- 2.7.4