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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,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 9F74AC43215 for ; Wed, 27 Nov 2019 21:24:26 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 762E6215F2 for ; Wed, 27 Nov 2019 21:24:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574889866; bh=mKp2s/blIgMGrwn5l+GuCYtectkjp5AVSv8RFFXlJYI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=f0b10zBypMRxpSxVgGv+iqJg7VUvblOC4HmtmA4+M76556ae1mb30n26vKQhC8xZY MhN6cw8KGdPtdN9KFs9sqpPye+rCzIRTM3zzDDzsttJck1YsQJCgrDRA/dflveGTF4 Hk+Ey8ovNuIbB7LiB4RQeYLmnUzwUFtCXfO5m6Aw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732024AbfK0VDT (ORCPT ); Wed, 27 Nov 2019 16:03:19 -0500 Received: from mail.kernel.org ([198.145.29.99]:56508 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732004AbfK0VDS (ORCPT ); Wed, 27 Nov 2019 16:03:18 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id DC8B02086A; Wed, 27 Nov 2019 21:03:17 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1574888598; bh=mKp2s/blIgMGrwn5l+GuCYtectkjp5AVSv8RFFXlJYI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WreGH7UllX2H0fPMs9WPzY5DDYT7cxnVguo91OljobDH3QP06iNJk8xs++tj2apzH 2aZ/0THM68L6ifFi+ZXNOc8d86X5hxV3ZbWuHz/R4ueKsDigud3gA0xTgF5wT5RURT W9JmDx4PziQ3MeTrm3LizRIh6jntgD5KlwYTyHTg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Changwei Ge , Andrew Morton , Mark Fasheh , Joel Becker , Junxiao Bi , Joseph Qi , Linus Torvalds , Sasha Levin Subject: [PATCH 4.19 197/306] ocfs2: dont use iocb when EIOCBQUEUED returns Date: Wed, 27 Nov 2019 21:30:47 +0100 Message-Id: <20191127203129.589297656@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191127203114.766709977@linuxfoundation.org> References: <20191127203114.766709977@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Changwei Ge [ Upstream commit 9e985787750db8aae87f02b67e908f28ac4d6b83 ] When -EIOCBQUEUED returns, it means that aio_complete() will be called from dio_complete(), which is an asynchronous progress against write_iter. Generally, IO is a very slow progress than executing instruction, but we still can't take the risk to access a freed iocb. And we do face a BUG crash issue. Using the crash tool, iocb is obviously freed already. crash> struct -x kiocb ffff881a350f5900 struct kiocb { ki_filp = 0xffff881a350f5a80, ki_pos = 0x0, ki_complete = 0x0, private = 0x0, ki_flags = 0x0 } And the backtrace shows: ocfs2_file_write_iter+0xcaa/0xd00 [ocfs2] aio_run_iocb+0x229/0x2f0 do_io_submit+0x291/0x540 SyS_io_submit+0x10/0x20 system_call_fastpath+0x16/0x75 Link: http://lkml.kernel.org/r/1523361653-14439-1-git-send-email-ge.changwei@h3c.com Signed-off-by: Changwei Ge Reviewed-by: Andrew Morton Cc: Mark Fasheh Cc: Joel Becker Cc: Junxiao Bi Cc: Joseph Qi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- fs/ocfs2/file.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c index a847fe52c56ee..a3e077fcfeb9b 100644 --- a/fs/ocfs2/file.c +++ b/fs/ocfs2/file.c @@ -2389,7 +2389,7 @@ static ssize_t ocfs2_file_write_iter(struct kiocb *iocb, written = __generic_file_write_iter(iocb, from); /* buffered aio wouldn't have proper lock coverage today */ - BUG_ON(written == -EIOCBQUEUED && !(iocb->ki_flags & IOCB_DIRECT)); + BUG_ON(written == -EIOCBQUEUED && !direct_io); /* * deep in g_f_a_w_n()->ocfs2_direct_IO we pass in a ocfs2_dio_end_io @@ -2509,7 +2509,7 @@ static ssize_t ocfs2_file_read_iter(struct kiocb *iocb, trace_generic_file_read_iter_ret(ret); /* buffered aio wouldn't have proper lock coverage today */ - BUG_ON(ret == -EIOCBQUEUED && !(iocb->ki_flags & IOCB_DIRECT)); + BUG_ON(ret == -EIOCBQUEUED && !direct_io); /* see ocfs2_file_write_iter */ if (ret == -EIOCBQUEUED || !ocfs2_iocb_is_rw_locked(iocb)) { -- 2.20.1