From patchwork Mon Mar 1 16:13:30 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 390195 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=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, 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 84175C433E0 for ; Mon, 1 Mar 2021 16:44:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 31F1E6502F for ; Mon, 1 Mar 2021 16:44:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232874AbhCAQmU (ORCPT ); Mon, 1 Mar 2021 11:42:20 -0500 Received: from mail.kernel.org ([198.145.29.99]:41574 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234298AbhCAQej (ORCPT ); Mon, 1 Mar 2021 11:34:39 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 756E064E5C; Mon, 1 Mar 2021 16:25:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1614615924; bh=PL6RSaoPHOuZo46oVlz9RB7IohHUTP5ViUrqOxBSSuU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=d4uFyIVnqm3bXLPMMRVh0LeqW1pnWQ6ZfVqhzbwVQpPnlgw2faiD5xWaSL1xbtyVl TEq5ZRqWwcu7fNpXAzfSpDZ2SQRtIFoqfj66NFjPe/UAMCeiveaUH2tYWYMzkwXhFe 1iTRF5OQOrM5NqxUypYbvn6TOi0r9O+Lufloj5dM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Wim Osterholt , Jiri Kosina , Denis Efremov , Kurt Garloff Subject: [PATCH 4.9 109/134] floppy: reintroduce O_NDELAY fix Date: Mon, 1 Mar 2021 17:13:30 +0100 Message-Id: <20210301161018.937734728@linuxfoundation.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210301161013.585393984@linuxfoundation.org> References: <20210301161013.585393984@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Jiri Kosina commit 8a0c014cd20516ade9654fc13b51345ec58e7be8 upstream. 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. Link: https://lore.kernel.org/r/nycvar.YFH.7.76.2101221209060.5622@cbobk.fhfr.pm 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 Signed-off-by: Denis Efremov Signed-off-by: Greg Kroah-Hartman --- drivers/block/floppy.c | 27 ++++++++++++++------------- 1 file changed, 14 insertions(+), 13 deletions(-) --- a/drivers/block/floppy.c +++ b/drivers/block/floppy.c @@ -4067,21 +4067,22 @@ static int floppy_open(struct block_devi if (UFDCS->rawcmd == 1) UFDCS->rawcmd = 2; - if (!(mode & FMODE_NDELAY)) { - if (mode & (FMODE_READ|FMODE_WRITE)) { - UDRS->last_checked = 0; - clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags); - check_disk_change(bdev); - if (test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags)) - goto out; - if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags)) - goto out; - } - res = -EROFS; - if ((mode & FMODE_WRITE) && - !test_bit(FD_DISK_WRITABLE_BIT, &UDRS->flags)) + if (mode & (FMODE_READ|FMODE_WRITE)) { + UDRS->last_checked = 0; + clear_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags); + check_disk_change(bdev); + if (test_bit(FD_DISK_CHANGED_BIT, &UDRS->flags)) + goto out; + if (test_bit(FD_OPEN_SHOULD_FAIL_BIT, &UDRS->flags)) goto out; } + + res = -EROFS; + + if ((mode & FMODE_WRITE) && + !test_bit(FD_DISK_WRITABLE_BIT, &UDRS->flags)) + goto out; + mutex_unlock(&open_lock); mutex_unlock(&floppy_mutex); return 0;