From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753335AbdLMCaA (ORCPT ); Tue, 12 Dec 2017 21:30:00 -0500 Received: from omzsmtpe03.verizonbusiness.com ([199.249.25.208]:42940 "EHLO omzsmtpe03.verizonbusiness.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753057AbdLMB7l (ORCPT ); Tue, 12 Dec 2017 20:59:41 -0500 From: alexander.levin@verizon.com Cc: Dan Carpenter , "David S . Miller" , alexander.levin@verizon.com X-Host: endeavour.tdc.vzwcorp.com To: "linux-kernel@vger.kernel.org" , "stable@vger.kernel.org" Subject: [PATCH AUTOSEL for 4.4 09/59] bna: integer overflow bug in debugfs Thread-Topic: [PATCH AUTOSEL for 4.4 09/59] bna: integer overflow bug in debugfs Thread-Index: AQHTc7XebrjU/xOoV0uVoVia3s5hTA== Date: Wed, 13 Dec 2017 01:58:27 +0000 Message-ID: <20171213015817.6950-9-alexander.levin@verizon.com> References: <20171213015817.6950-1-alexander.levin@verizon.com> In-Reply-To: <20171213015817.6950-1-alexander.levin@verizon.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-exchange-messagesentrepresentingtype: 1 x-ms-exchange-transport-fromentityheader: Hosted x-originating-ip: [10.144.60.250] Content-Type: text/plain; charset="iso-8859-1" MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by nfs id vBD2U47k018964 From: Dan Carpenter [ Upstream commit 13e2d5187f6b965ba3556caedb914baf81b98ed2 ] We could allocate less memory than intended because we do: bnad->regdata = kzalloc(len << 2, GFP_KERNEL); The shift can overflow leading to a crash. This is debugfs code so the impact is very small. Fixes: 7afc5dbde091 ("bna: Add debugfs interface.") Signed-off-by: Dan Carpenter Acked-by: Rasesh Mody Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/net/ethernet/brocade/bna/bnad_debugfs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/ethernet/brocade/bna/bnad_debugfs.c b/drivers/net/ethernet/brocade/bna/bnad_debugfs.c index 8fc246ea1fb8..a4ad782007ce 100644 --- a/drivers/net/ethernet/brocade/bna/bnad_debugfs.c +++ b/drivers/net/ethernet/brocade/bna/bnad_debugfs.c @@ -324,7 +324,7 @@ bnad_debugfs_write_regrd(struct file *file, const char __user *buf, return PTR_ERR(kern_buf); rc = sscanf(kern_buf, "%x:%x", &addr, &len); - if (rc < 2) { + if (rc < 2 || len > UINT_MAX >> 2) { netdev_warn(bnad->netdev, "failed to read user buffer\n"); kfree(kern_buf); return -EINVAL; -- 2.11.0