From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.kernel.org ([198.145.29.99]:57672 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935473AbeE1KJc (ORCPT ); Mon, 28 May 2018 06:09:32 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Li Ning , Jeremy Cline , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 3.18 088/185] scsi: sd: Keep disk read-only when re-reading partition Date: Mon, 28 May 2018 12:02:09 +0200 Message-Id: <20180528100058.148193658@linuxfoundation.org> In-Reply-To: <20180528100050.700971285@linuxfoundation.org> References: <20180528100050.700971285@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: stable-owner@vger.kernel.org List-ID: 3.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeremy Cline [ Upstream commit 20bd1d026aacc5399464f8328f305985c493cde3 ] If the read-only flag is true on a SCSI disk, re-reading the partition table sets the flag back to false. To observe this bug, you can run: 1. blockdev --setro /dev/sda 2. blockdev --rereadpt /dev/sda 3. blockdev --getro /dev/sda This commit reads the disk's old state and combines it with the device disk-reported state rather than unconditionally marking it as RW. Reported-by: Li Ning Signed-off-by: Jeremy Cline Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- drivers/scsi/sd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -2318,6 +2318,7 @@ sd_read_write_protect_flag(struct scsi_d int res; struct scsi_device *sdp = sdkp->device; struct scsi_mode_data data; + int disk_ro = get_disk_ro(sdkp->disk); int old_wp = sdkp->write_prot; set_disk_ro(sdkp->disk, 0); @@ -2358,7 +2359,7 @@ sd_read_write_protect_flag(struct scsi_d "Test WP failed, assume Write Enabled\n"); } else { sdkp->write_prot = ((data.device_specific & 0x80) != 0); - set_disk_ro(sdkp->disk, sdkp->write_prot); + set_disk_ro(sdkp->disk, sdkp->write_prot || disk_ro); if (sdkp->first_scan || old_wp != sdkp->write_prot) { sd_printk(KERN_NOTICE, sdkp, "Write Protect is %s\n", sdkp->write_prot ? "on" : "off");