From patchwork Fri Jan 22 11:13:20 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Kosina X-Patchwork-Id: 12039003 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=-17.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 35BA6C433E6 for ; Fri, 22 Jan 2021 11:16:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EDF9A22DBF for ; Fri, 22 Jan 2021 11:16:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727556AbhAVLQC (ORCPT ); Fri, 22 Jan 2021 06:16:02 -0500 Received: from mail.kernel.org ([198.145.29.99]:55864 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727722AbhAVLOH (ORCPT ); Fri, 22 Jan 2021 06:14:07 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id B9A752246B; Fri, 22 Jan 2021 11:13:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1611314004; bh=qKaCrMSE3znTlxna118B4y/k0MOaw8ankwk0D2+SXQ8=; h=Date:From:To:cc:Subject:In-Reply-To:References:From; b=llYcg9itg23JAsDCeIqdGYyxPEo5HgCT4RdQmnUFBA5MVHQ/S/i6pfDgF29sf8JOo e14YJUHO+KVoU/rW8UKt9tZe7mAo5EkNjCLqp42Mp21D+9haLizwcU1Yvi3vz1qh3O oxbMFmiMLL0f0FdcgtAO5Po+1TD0WbL8zIGSC8Ksf2t3003gAIAR13ge0e4JXhFeSX ehSIq6JHblCjuhm0k9dpBaisBIwzI+KcGSK6KDqjcgqj+m0KEmM9VNwuVyyiQWfblw 7VG9P8iC2aR2Thdciscfr33/ewYyPLmQv8J2aGIa+X5IhJmHVUuO/cn5D40WdB/z73 pwFezGuVl9FqQ== Date: Fri, 22 Jan 2021 12:13:20 +0100 (CET) From: Jiri Kosina To: Denis Efremov , Jens Axboe cc: linux-kernel@vger.kernel.org, linux-block@vger.kernel.org, Wim Osterholt , Kurt Garloff Subject: [PATCH] floppy: reintroduce O_NDELAY fix In-Reply-To: Message-ID: References: <20160610230255.GA27770@djo.tudelft.nl> <20160614184308.GA6188@djo.tudelft.nl> <20160615132040.GZ14480@ZenIV.linux.org.uk> <20160615224722.GA9545@djo.tudelft.nl> <9c713fa8-9da1-47b5-0d5d-92f4cd13493a@kernel.dk> <5cb57175-7f0b-5536-925d-337241bcda93@linux.com> User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org From: Jiri Kosina This issue was originally fixed in 09954bad4 ("floppy: refactor open() flags handling"). The fix as a side-effect, however, introduce issue for open(O_ACCMODE) that is being used for ioctl-only open. I wrote a fix for that, but instead of it being merged, full revert of 09954bad4 was performed, re-introducing the O_NDELAY / O_NONBLOCK issue, and it strikes again. This is a forward-port of the original fix to current codebase; the original submission had the changelog below: ==== Commit 09954bad4 ("floppy: refactor open() flags handling"), as a side-effect, causes open(/dev/fdX, O_ACCMODE) to fail. It turns out that this is being used setfdprm userspace for ioctl-only open(). Reintroduce back the original behavior wrt !(FMODE_READ|FMODE_WRITE) modes, while still keeping the original O_NDELAY bug fixed. Cc: stable@vger.kernel.org Reported-by: Wim Osterholt Tested-by: Wim Osterholt Reported-and-tested-by: Kurt Garloff Fixes: 09954bad4 ("floppy: refactor open() flags handling") Fixes: f2791e7ead ("Revert "floppy: refactor open() flags handling"") Signed-off-by: Jiri Kosina --- drivers/block/floppy.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c index dfe1dfc901cc..0b71292d9d5a 100644 --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -4121,23 +4121,23 @@ static int floppy_open(struct block_device *bdev, fmode_t mode) if (fdc_state[FDC(drive)].rawcmd == 1) fdc_state[FDC(drive)].rawcmd = 2; - if (!(mode & FMODE_NDELAY)) { - if (mode & (FMODE_READ|FMODE_WRITE)) { - drive_state[drive].last_checked = 0; - clear_bit(FD_OPEN_SHOULD_FAIL_BIT, - &drive_state[drive].flags); - if (bdev_check_media_change(bdev)) - floppy_revalidate(bdev->bd_disk); - if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags)) - goto out; - if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags)) - goto out; - } - res = -EROFS; - if ((mode & FMODE_WRITE) && - !test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags)) + if (mode & (FMODE_READ|FMODE_WRITE)) { + drive_state[drive].last_checked = 0; + clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags); + if (bdev_check_media_change(bdev)) + floppy_revalidate(bdev->bd_disk); + if (test_bit(FD_DISK_CHANGED_BIT, &drive_state[drive].flags)) + goto out; + if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &drive_state[drive].flags)) goto out; } + + res = -EROFS; + + if ((mode & FMODE_WRITE) && + !test_bit(FD_DISK_WRITABLE_BIT, &drive_state[drive].flags)) + goto out; + mutex_unlock(&open_lock); mutex_unlock(&floppy_mutex); return 0;