From patchwork Fri Jun 19 14:33:09 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 223641 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=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 8FD56C433E1 for ; Fri, 19 Jun 2020 16:50:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6E09820720 for ; Fri, 19 Jun 2020 16:50:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592585453; bh=6UcsDGqhZhBV6wGC3oJUGPdAQNjIkMJhcD/PIC8nYb8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=dwynbcDgzgnalMh9msKlI+TI/90Usf/qqUEIHOagDUkVFlEHyLAfRB/wP8nKvaJ0h NNqkdsyOlerIzZ/wJicD7qPyYKdaqJYvIzKYcV5qABtavj2/i53c7j8UZqOXlQKHFd /EPYrEPiu3S5Dz7Yo8okkcFCjd+ebyC8l7zDTuEA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2395513AbgFSQuv (ORCPT ); Fri, 19 Jun 2020 12:50:51 -0400 Received: from mail.kernel.org ([198.145.29.99]:55638 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387543AbgFSOib (ORCPT ); Fri, 19 Jun 2020 10:38:31 -0400 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 2899120DD4; Fri, 19 Jun 2020 14:38:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1592577510; bh=6UcsDGqhZhBV6wGC3oJUGPdAQNjIkMJhcD/PIC8nYb8=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=cGjvu5HUhO1xxM7POKqfs/L7Ie1aC4NpNgEn3etsYH9vqHzIVrS9Hrzuc0BUf26fh HkBaEQj/Y1IQB+45uEqL4eME3T6IQzoroYui253+ITwFVzcgRoJ4HBKm+/eKZ8aq0m CmIstJSvCqJ3gkNBnY69squw9N/ZRkh8YG20TmGQ= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Nikolay Borisov , Josef Bacik , Johannes Thumshirn , Omar Sandoval , David Sterba , Sasha Levin Subject: [PATCH 4.4 080/101] btrfs: fix error handling when submitting direct I/O bio Date: Fri, 19 Jun 2020 16:33:09 +0200 Message-Id: <20200619141618.179542740@linuxfoundation.org> X-Mailer: git-send-email 2.27.0 In-Reply-To: <20200619141614.001544111@linuxfoundation.org> References: <20200619141614.001544111@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Omar Sandoval [ Upstream commit 6d3113a193e3385c72240096fe397618ecab6e43 ] In btrfs_submit_direct_hook(), if a direct I/O write doesn't span a RAID stripe or chunk, we submit orig_bio without cloning it. In this case, we don't increment pending_bios. Then, if btrfs_submit_dio_bio() fails, we decrement pending_bios to -1, and we never complete orig_bio. Fix it by initializing pending_bios to 1 instead of incrementing later. Fixing this exposes another bug: we put orig_bio prematurely and then put it again from end_io. Fix it by not putting orig_bio. After this change, pending_bios is really more of a reference count, but I'll leave that cleanup separate to keep the fix small. Fixes: e65e15355429 ("btrfs: fix panic caused by direct IO") CC: stable@vger.kernel.org # 4.4+ Reviewed-by: Nikolay Borisov Reviewed-by: Josef Bacik Reviewed-by: Johannes Thumshirn Signed-off-by: Omar Sandoval Signed-off-by: David Sterba Signed-off-by: Sasha Levin --- fs/btrfs/inode.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c index 548e9cd1a337..972475eeb2dd 100644 --- a/fs/btrfs/inode.c +++ b/fs/btrfs/inode.c @@ -8294,7 +8294,6 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, bio->bi_private = dip; bio->bi_end_io = btrfs_end_dio_bio; btrfs_io_bio(bio)->logical = file_offset; - atomic_inc(&dip->pending_bios); while (bvec <= (orig_bio->bi_io_vec + orig_bio->bi_vcnt - 1)) { if (map_length < submit_len + bvec->bv_len || @@ -8351,7 +8350,8 @@ static int btrfs_submit_direct_hook(int rw, struct btrfs_dio_private *dip, if (!ret) return 0; - bio_put(bio); + if (bio != orig_bio) + bio_put(bio); out_err: dip->errors = 1; /* @@ -8398,7 +8398,7 @@ static void btrfs_submit_direct(int rw, struct bio *dio_bio, io_bio->bi_private = dip; dip->orig_bio = io_bio; dip->dio_bio = dio_bio; - atomic_set(&dip->pending_bios, 0); + atomic_set(&dip->pending_bios, 1); btrfs_bio = btrfs_io_bio(io_bio); btrfs_bio->logical = file_offset;