lkml.org 
[lkml]   [2017]   [Dec]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.14 161/164] dm raid: fix panic when attempting to force a raid to sync
Date
4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

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- DMERR("superblock size of a logical block is no longer valid");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+ DMERR("superblock size of a logical block is no longer valid");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) {

\
 
 \ /
  Last update: 2017-12-12 14:38    [W:0.483 / U:4.548 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site