From: Heinz Mauelshagen <heinzm@xxxxxxxxxx>
Requesting a sync on an active raid device via a table reload
(see 'sync' parameter in Documentation/device-mapper/dm-raid.txt)
prevents the super_load() call defining the superblock size (rdev->sb_size)
thus super_sync()->memset() called later will oops.
Fix by moving the initialization of the superblock start and size
out of super_load() to the caller.
Resolves: rhbz1226440
---
drivers/md/dm-raid.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index 2245d06d2045..a25eebd98996 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -2143,13 +2143,6 @@ static int super_load(struct md_rdev *rdev, struct md_rdev *refdev)
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- DMERR("superblock size of a logical block is no longer valid");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_target *ti, struct raid_set *rs)
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+ DMERR("superblock size of a logical block is no longer valid");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_target *ti, struct raid_set *rs)
if (test_bit(__CTR_FLAG_SYNC, &rs->ctr_flags))
continue;
- if (!rdev->meta_bdev)
- continue;
-
r = super_load(rdev, freshest);
switch (r) {
--
2.13.6
--
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