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=-16.1 required=3.0 tests=BAYES_00,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=unavailable 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 57B05C43463 for ; Fri, 18 Sep 2020 02:15:02 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 11F91239A1 for ; Fri, 18 Sep 2020 02:15:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395302; bh=hZd/IcB4cD8T2+DK6lwBoe0pNDwO4mV5CW6l+OMgXiY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=kmB6bGImH0HWTahy7rWSD+0gtKqpgWjtvn7gC8478vrAFtFY5NZc56Z1acJSupmEv abvNKYc0XwGLz/e8YXhHxbHxzTTMhPkOM0b7vwfpGOTKiYKaqJ/PW8f2aCFlyapl31 hk37nUbgitoDh03pymG29fkfD6YbZYNd5ljASSDw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729165AbgIRCPA (ORCPT ); Thu, 17 Sep 2020 22:15:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:43268 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729142AbgIRCOv (ORCPT ); Thu, 17 Sep 2020 22:14:51 -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 916AF2376E; Fri, 18 Sep 2020 02:14:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1600395290; bh=hZd/IcB4cD8T2+DK6lwBoe0pNDwO4mV5CW6l+OMgXiY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CHhfkty7G9hy8qTWUjzfHURymZ0jcMEOsDbA6wIaqy338LHgw9veS7VO6O46Mt0JX //VoPQen1T1F0xbZ57V12K5FkCi1T8YMdvITPpWTFRNAVk6BUd0A79+HQ8qNHr5Dln pm82tivuJQlS3b0pIy1VpUZ3X8oiVvdxEJ3YMh0g= From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Javed Hasan , Girish Basrur , Saurav Kashyap , Shyam Sundar , "Martin K . Petersen" , Sasha Levin , fcoe-devel@open-fcoe.org, linux-scsi@vger.kernel.org Subject: [PATCH AUTOSEL 4.14 124/127] scsi: libfc: Skip additional kref updating work event Date: Thu, 17 Sep 2020 22:12:17 -0400 Message-Id: <20200918021220.2066485-124-sashal@kernel.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20200918021220.2066485-1-sashal@kernel.org> References: <20200918021220.2066485-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Javed Hasan [ Upstream commit 823a65409c8990f64c5693af98ce0e7819975cba ] When an rport event (RPORT_EV_READY) is updated without work being queued, avoid taking an additional reference. This issue was leading to memory leak. Trace from KMEMLEAK tool: unreferenced object 0xffff8888259e8780 (size 512): comm "kworker/2:1", jiffies 4433237386 (age 113021.971s) hex dump (first 32 bytes): 58 0a ec cf 83 88 ff ff 00 00 00 00 00 00 00 00 01 00 00 00 08 00 00 00 13 7d f0 1e 0e 00 00 10 backtrace: [<000000006b25760f>] fc_rport_recv_req+0x3c6/0x18f0 [libfc] [<00000000f208d994>] fc_lport_recv_els_req+0x120/0x8a0 [libfc] [<00000000a9c437b8>] fc_lport_recv+0xb9/0x130 [libfc] [<00000000a9c437b8>] fc_lport_recv+0xb9/0x130 [libfc] [<00000000ad5be37b>] qedf_ll2_process_skb+0x73d/0xad0 [qedf] [<00000000e0eb6893>] process_one_work+0x382/0x6c0 [<000000002dfd9e21>] worker_thread+0x57/0x5c0 [<00000000b648204f>] kthread+0x1a0/0x1c0 [<0000000072f5ab20>] ret_from_fork+0x35/0x40 [<000000001d5c05d8>] 0xffffffffffffffff Below is the log sequence which leads to memory leak. Here we get the RPORT_EV_READY and RPORT_EV_STOP back to back, which lead to overwrite the event RPORT_EV_READY by event RPORT_EV_STOP. Because of this, kref_count gets incremented by 1. kernel: host0: rport fffce5: Received PLOGI request kernel: host0: rport fffce5: Received PLOGI in INIT state kernel: host0: rport fffce5: Port is Ready kernel: host0: rport fffce5: Received PRLI request while in state Ready kernel: host0: rport fffce5: PRLI rspp type 8 active 1 passive 0 kernel: host0: rport fffce5: Received LOGO request while in state Ready kernel: host0: rport fffce5: Delete port kernel: host0: rport fffce5: Received PLOGI request kernel: host0: rport fffce5: Received PLOGI in state Delete - send busy kernel: host0: rport fffce5: work event 3 kernel: host0: rport fffce5: lld callback ev 3 kernel: host0: rport fffce5: work delete Link: https://lore.kernel.org/r/20200626094959.32151-1-jhasan@marvell.com Reviewed-by: Girish Basrur Reviewed-by: Saurav Kashyap Reviewed-by: Shyam Sundar Signed-off-by: Javed Hasan Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/libfc/fc_rport.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c index a9137f64befa0..669cf3553a77d 100644 --- a/drivers/scsi/libfc/fc_rport.c +++ b/drivers/scsi/libfc/fc_rport.c @@ -495,10 +495,11 @@ static void fc_rport_enter_delete(struct fc_rport_priv *rdata, fc_rport_state_enter(rdata, RPORT_ST_DELETE); - kref_get(&rdata->kref); - if (rdata->event == RPORT_EV_NONE && - !queue_work(rport_event_queue, &rdata->event_work)) - kref_put(&rdata->kref, fc_rport_destroy); + if (rdata->event == RPORT_EV_NONE) { + kref_get(&rdata->kref); + if (!queue_work(rport_event_queue, &rdata->event_work)) + kref_put(&rdata->kref, fc_rport_destroy); + } rdata->event = event; } -- 2.25.1