linux-kernel - [PATCH v2] md/raid5: don't allow concurrent reshape with recovery

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-Id: <20230529133410.2125914-1-yukuai1@huaweicloud.com>
Date:   Mon, 29 May 2023 21:34:10 +0800
From:   Yu Kuai <yukuai1@...weicloud.com>
To:     song@...nel.org, pmenzel@...gen.mpg.de
Cc:     linux-raid@...r.kernel.org, linux-kernel@...r.kernel.org,
        yukuai3@...wei.com, yukuai1@...weicloud.com, yi.zhang@...wei.com,
        yangerkun@...wei.com
Subject: [PATCH v2] md/raid5: don't allow concurrent reshape with recovery

From: Yu Kuai <yukuai3@...wei.com>

Commit 0aecb06e2249 ("md/raid5: don't allow replacement while reshape
is in progress") fixes that replacement can be set if reshape is
interrupted, which will cause that array can't be assembled.

There is a similar problem on the other side, if recovery is
interrupted, then reshape can start, which will cause the same problem.

Fix the problem by not starting to reshape while recovery is still in
progress.

Signed-off-by: Yu Kuai <yukuai3@...wei.com>
---
Changes in v2:
 - fix some typo in commit message.

 drivers/md/raid5.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 8686d629e3f2..6615abf54d3f 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -8525,6 +8525,7 @@ static int raid5_start_reshape(struct mddev *mddev)
 	struct r5conf *conf = mddev->private;
 	struct md_rdev *rdev;
 	int spares = 0;
+	int i;
 	unsigned long flags;
 
 	if (test_bit(MD_RECOVERY_RUNNING, &mddev->recovery))
@@ -8536,6 +8537,13 @@ static int raid5_start_reshape(struct mddev *mddev)
 	if (has_failed(conf))
 		return -EINVAL;
 
+	/* raid5 can't handle concurrent reshape and recovery */
+	if (mddev->recovery_cp < MaxSector)
+		return -EBUSY;
+	for (i = 0; i < conf->raid_disks; i++)
+		if (rdev_mdlock_deref(mddev, conf->disks[i].replacement))
+			return -EBUSY;
+
 	rdev_for_each(rdev, mddev) {
 		if (!test_bit(In_sync, &rdev->flags)
 		    && !test_bit(Faulty, &rdev->flags))
-- 
2.39.2