From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 99D7CFC6194 for ; Fri, 8 Nov 2019 11:40:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6721221D7F for ; Fri, 8 Nov 2019 11:40:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573213225; bh=SbUMUnJim/VLR30Kb/P0spszcZpvqXA7aR6Fp6ri25M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=m4n9/JZaaxM5HdvGRVknOOh4H3KlwbeIiq4vlml1Nbb/M5m2JnHXu5v0CX4ho60Nh 3TbOlXh/rfeDNRSE/WZRfTNkXQLZqbkBbQe5jPHANwNcjV8IsNvBvqF5AStdxbgwyu CiOMUvvPnf5DrRXB/FvuhySHq+Qnb5OVjDsro+g8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388582AbfKHLkW (ORCPT ); Fri, 8 Nov 2019 06:40:22 -0500 Received: from mail.kernel.org ([198.145.29.99]:53306 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732112AbfKHLkV (ORCPT ); Fri, 8 Nov 2019 06:40:21 -0500 Received: from sasha-vm.mshome.net (c-73-47-72-35.hsd1.nh.comcast.net [73.47.72.35]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9F27221D7F; Fri, 8 Nov 2019 11:40:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573213220; bh=SbUMUnJim/VLR30Kb/P0spszcZpvqXA7aR6Fp6ri25M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=x1lIGmfqshZUnBzpx1fQl6v/7QFqCftNA0hGDgev0l5afRjWjU3rlTBoVWTrbQ3pg fA8WGWM+sk/FR+lz5yqnJ3OfJHCQB5Mki5a1lrOKrxVfoc5ziLJu5cadSDxxNiIBcH sPAvoDQszeZJoVSYSfYw9xPCdzcrysBr7t6MqMOg= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Muhammad Sammar , Feras Daoud , Leon Romanovsky , Jason Gunthorpe , Sasha Levin , linux-rdma@vger.kernel.org Subject: [PATCH AUTOSEL 4.19 097/205] IB/ipoib: Ensure that MTU isn't less than minimum permitted Date: Fri, 8 Nov 2019 06:36:04 -0500 Message-Id: <20191108113752.12502-97-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191108113752.12502-1-sashal@kernel.org> References: <20191108113752.12502-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-rdma-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-rdma@vger.kernel.org From: Muhammad Sammar [ Upstream commit 142a9c287613560edf5a03c8d142c8b6ebc1995b ] It is illegal to change MTU to a value lower than the minimum MTU stated in ethernet spec. In addition to that we need to add 4 bytes for encapsulation header (IPOIB_ENCAP_LEN). Before "ifconfig ib0 mtu 0" command, succeeds while it obviously shouldn't. Signed-off-by: Muhammad Sammar Reviewed-by: Feras Daoud Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/ulp/ipoib/ipoib_main.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/infiniband/ulp/ipoib/ipoib_main.c b/drivers/infiniband/ulp/ipoib/ipoib_main.c index 78dd36daac00e..d8cb5bbe6eb58 100644 --- a/drivers/infiniband/ulp/ipoib/ipoib_main.c +++ b/drivers/infiniband/ulp/ipoib/ipoib_main.c @@ -243,7 +243,8 @@ static int ipoib_change_mtu(struct net_device *dev, int new_mtu) return 0; } - if (new_mtu > IPOIB_UD_MTU(priv->max_ib_mtu)) + if (new_mtu < (ETH_MIN_MTU + IPOIB_ENCAP_LEN) || + new_mtu > IPOIB_UD_MTU(priv->max_ib_mtu)) return -EINVAL; priv->admin_mtu = new_mtu; -- 2.20.1