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 A0526C43603 for ; Tue, 10 Dec 2019 22:35:49 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 66CEC207FF for ; Tue, 10 Dec 2019 22:35:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576017349; bh=A47+vKFAqvpWsAajzfDUfLGO+4fxidIRoS8mEKh+bEw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=J0aqn3/KOA9dAOO4n8Fpnc5Axw8vQFAfVzXqq+0WAoCamBeMTGcol7jbnxirjw2D+ 22/jliUDM6fWX3n4LwY9cAt/2uJ+6l+l7S5iwLlQW8fDpJg0qjkGfCyOAvLDhwu3UN 0/R+cOYVb17i+Dcmk2+6Bgz0Traue4LjpJUuWIDI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730503AbfLJWfs (ORCPT ); Tue, 10 Dec 2019 17:35:48 -0500 Received: from mail.kernel.org ([198.145.29.99]:55974 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730346AbfLJWea (ORCPT ); Tue, 10 Dec 2019 17:34:30 -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 B886D20828; Tue, 10 Dec 2019 22:34:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1576017269; bh=A47+vKFAqvpWsAajzfDUfLGO+4fxidIRoS8mEKh+bEw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tPMdn8U69z/pjadcYEq7T+DwYN440AZRwRSk21DiCRNidcbjxSNLbmo8kxqTxAvzS 4Igj0jlizF3ztVd1ydm4vrfIT9Mn7EVtIUqz4HapVozgJo9aiaIYJXu97CVDdSqkXe H+mgLme3ocgdbN+Jfx6eMRHnfYEbvGlIVhfukHfA= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Viresh Kumar , Greg Kroah-Hartman , Jason Gunthorpe , Sasha Levin , linux-rdma@vger.kernel.org Subject: [PATCH AUTOSEL 4.4 61/71] RDMA/qib: Validate ->show()/store() callbacks before calling them Date: Tue, 10 Dec 2019 17:33:06 -0500 Message-Id: <20191210223316.14988-61-sashal@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191210223316.14988-1-sashal@kernel.org> References: <20191210223316.14988-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Viresh Kumar [ Upstream commit 7ee23491b39259ae83899dd93b2a29ef0f22f0a7 ] The permissions of the read-only or write-only sysfs files can be changed (as root) and the user can then try to read a write-only file or write to a read-only file which will lead to kernel crash here. Protect against that by always validating the show/store callbacks. Link: https://lore.kernel.org/r/d45cc26361a174ae12dbb86c994ef334d257924b.1573096807.git.viresh.kumar@linaro.org Signed-off-by: Viresh Kumar Reviewed-by: Greg Kroah-Hartman Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin --- drivers/infiniband/hw/qib/qib_sysfs.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/infiniband/hw/qib/qib_sysfs.c b/drivers/infiniband/hw/qib/qib_sysfs.c index 81f56cdff2bc2..3ae82202cdb55 100644 --- a/drivers/infiniband/hw/qib/qib_sysfs.c +++ b/drivers/infiniband/hw/qib/qib_sysfs.c @@ -301,6 +301,9 @@ static ssize_t qib_portattr_show(struct kobject *kobj, struct qib_pportdata *ppd = container_of(kobj, struct qib_pportdata, pport_kobj); + if (!pattr->show) + return -EIO; + return pattr->show(ppd, buf); } @@ -312,6 +315,9 @@ static ssize_t qib_portattr_store(struct kobject *kobj, struct qib_pportdata *ppd = container_of(kobj, struct qib_pportdata, pport_kobj); + if (!pattr->store) + return -EIO; + return pattr->store(ppd, buf, len); } -- 2.20.1