dm thin: don't allow messages to be sent to a pool target in READ_ONLY or FAIL mode
You can't modify the metadata in these modes. It's better to fail these
messages immediately than let the block-manager deny write locks on
metadata blocks. Otherwise these failed metadata changes will trigger
'needs_check' to get set in the metadata superblock -- requiring repair
using the thin_check utility.
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 4934789..07705ee 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -3385,6 +3385,12 @@
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
+ if (get_pool_mode(pool) >= PM_READ_ONLY) {
+ DMERR("%s: unable to service pool target messages in READ_ONLY or FAIL mode",
+ dm_device_name(pool->pool_md));
+ return -EINVAL;
+ }
+
if (!strcasecmp(argv[0], "create_thin"))
r = process_create_thin_mesg(argc, argv, pool);