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,URIBL_BLOCKED,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 E39A3C433E0 for ; Mon, 29 Jun 2020 20:15:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C31B22065D for ; Mon, 29 Jun 2020 20:15:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593461752; bh=e2QNlmsuQpPKWy51VFelmbUXLW8vI9Bet605hJcGwOs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=qYmP+tdIZzCPiCj/XfxaTO/3SsOVjEox/Y36WrDN8x3ZzSTbeIH+Pg8YlW+1SqCcr BIR2x3RTTv/fQhi6Id3KHhukaPTaFEIz4a/d3aVhkuN2PwGs0k9nc202Xwg3Rn2U2F MUCYvlSY4OJ+Hjek25eilLYKCI753iCtbvd9xXG8= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732819AbgF2UPt (ORCPT ); Mon, 29 Jun 2020 16:15:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:40570 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732821AbgF2TaR (ORCPT ); Mon, 29 Jun 2020 15:30:17 -0400 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 1956425243; Mon, 29 Jun 2020 15:35:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1593444960; bh=e2QNlmsuQpPKWy51VFelmbUXLW8vI9Bet605hJcGwOs=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lX3h5/+AgpPMo2oorRuCzuAPUG5Xi3yZgFW26yxyu2LC61YVkqMRRvWMiemVuyrFK EuD5lk/CTrToJJdbzUHrySq+S1ha3e0WgoldsbnJTEstDdMZiZxzML3AKGGm6af7VF wec0xhofIlFddwV0mM/M2zDL1NShCtPo+SdEHYuM= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Shay Drory , Maor Gottlieb , Leon Romanovsky , Jason Gunthorpe , Sasha Levin , Greg Kroah-Hartman Subject: [PATCH 4.19 058/131] IB/mad: Fix use after free when destroying MAD agent Date: Mon, 29 Jun 2020 11:33:49 -0400 Message-Id: <20200629153502.2494656-59-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200629153502.2494656-1-sashal@kernel.org> References: <20200629153502.2494656-1-sashal@kernel.org> MIME-Version: 1.0 X-KernelTest-Patch: http://kernel.org/pub/linux/kernel/v4.x/stable-review/patch-4.19.131-rc1.gz X-KernelTest-Tree: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git X-KernelTest-Branch: linux-4.19.y X-KernelTest-Patches: git://git.kernel.org/pub/scm/linux/kernel/git/stable/stable-queue.git X-KernelTest-Version: 4.19.131-rc1 X-KernelTest-Deadline: 2020-07-01T15:34+00:00 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: Shay Drory commit 116a1b9f1cb769b83e5adff323f977a62b1dcb2e upstream. Currently, when RMPP MADs are processed while the MAD agent is destroyed, it could result in use after free of rmpp_recv, as decribed below: cpu-0 cpu-1 ----- ----- ib_mad_recv_done() ib_mad_complete_recv() ib_process_rmpp_recv_wc() unregister_mad_agent() ib_cancel_rmpp_recvs() cancel_delayed_work() process_rmpp_data() start_rmpp() queue_delayed_work(rmpp_recv->cleanup_work) destroy_rmpp_recv() free_rmpp_recv() cleanup_work()[1] spin_lock_irqsave(&rmpp_recv->agent->lock) <-- use after free [1] cleanup_work() == recv_cleanup_handler Fix it by waiting for the MAD agent reference count becoming zero before calling to ib_cancel_rmpp_recvs(). Fixes: 9a41e38a467c ("IB/mad: Use IDR for agent IDs") Link: https://lore.kernel.org/r/20200621104738.54850-2-leon@kernel.org Signed-off-by: Shay Drory Reviewed-by: Maor Gottlieb Signed-off-by: Leon Romanovsky Signed-off-by: Jason Gunthorpe Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/infiniband/core/mad.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/infiniband/core/mad.c b/drivers/infiniband/core/mad.c index 218411282069b..cd82134d517be 100644 --- a/drivers/infiniband/core/mad.c +++ b/drivers/infiniband/core/mad.c @@ -615,10 +615,10 @@ static void unregister_mad_agent(struct ib_mad_agent_private *mad_agent_priv) idr_unlock(&ib_mad_clients); flush_workqueue(port_priv->wq); - ib_cancel_rmpp_recvs(mad_agent_priv); deref_mad_agent(mad_agent_priv); wait_for_completion(&mad_agent_priv->comp); + ib_cancel_rmpp_recvs(mad_agent_priv); ib_mad_agent_security_cleanup(&mad_agent_priv->agent); -- 2.25.1