This is a note to let you know that I've just added the patch titled
dm raid: fix panic when attempting to force a raid to sync
to the 4.14-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git%3Ba=su...
The filename of the patch is: dm-raid-fix-panic-when-attempting-to-force-a-raid-to-sync.patch and it can be found in the queue-4.14 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree, please let stable@vger.kernel.org know about it.
From foo@baz Tue Dec 12 10:32:42 CET 2017
From: Heinz Mauelshagen heinzm@redhat.com Date: Thu, 2 Nov 2017 19:58:28 +0100 Subject: dm raid: fix panic when attempting to force a raid to sync
From: Heinz Mauelshagen heinzm@redhat.com
[ Upstream commit 233978449074ca7e45d9c959f9ec612d1b852893 ]
Requesting a sync on an active raid device via a table reload (see 'sync' parameter in Documentation/device-mapper/dm-raid.txt) skips the super_load() call that defines the superblock size (rdev->sb_size) -- resulting in an oops if/when super_sync()->memset() is called.
Fix by moving the initialization of the superblock start and size out of super_load() to the caller (analyse_superblocks).
Signed-off-by: Heinz Mauelshagen heinzm@redhat.com Signed-off-by: Mike Snitzer snitzer@redhat.com Signed-off-by: Sasha Levin alexander.levin@verizon.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/md/dm-raid.c | 21 +++++++++++---------- 1 file changed, 11 insertions(+), 10 deletions(-)
--- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -2143,13 +2143,6 @@ static int super_load(struct md_rdev *rd struct dm_raid_superblock *refsb; uint64_t events_sb, events_refsb;
- rdev->sb_start = 0; - rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev); - if (rdev->sb_size < sizeof(*sb) || rdev->sb_size > PAGE_SIZE) { - DMERR("superblock size of a logical block is no longer valid"); - return -EINVAL; - } - r = read_disk_sb(rdev, rdev->sb_size, false); if (r) return r; @@ -2494,6 +2487,17 @@ static int analyse_superblocks(struct dm if (test_bit(Journal, &rdev->flags)) continue;
+ if (!rdev->meta_bdev) + continue; + + /* Set superblock offset/size for metadata device. */ + rdev->sb_start = 0; + rdev->sb_size = bdev_logical_block_size(rdev->meta_bdev); + if (rdev->sb_size < sizeof(struct dm_raid_superblock) || rdev->sb_size > PAGE_SIZE) { + DMERR("superblock size of a logical block is no longer valid"); + return -EINVAL; + } + /* * Skipping super_load due to CTR_FLAG_SYNC will cause * the array to undergo initialization again as @@ -2506,9 +2510,6 @@ static int analyse_superblocks(struct dm if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags)) continue;
- if (!rdev->meta_bdev) - continue; - r = super_load(rdev, freshest);
switch (r) {
Patches currently in stable-queue which might be from heinzm@redhat.com are
queue-4.14/dm-raid-fix-panic-when-attempting-to-force-a-raid-to-sync.patch