dm exception store: really fix type lookup

Fix exception store name handling.

We need to reference exception store by zero terminated string.

Fixes regression introduced in commit f6bd4eb73cdf2a5bf954e497972842f39cabb7e3

Cc: Yi Yang <yi.y.yang@intel.com>
Cc: Jonathan Brassow <jbrassow@redhat.com>
Cc: stable@kernel.org
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Milan Broz <mbroz@redhat.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>

diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c
index c3ae515..3710ff8 100644 (file)
--- a/drivers/md/dm-exception-store.c
+++ b/drivers/md/dm-exception-store.c
@@ -195,7 +195,7 @@ int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
                              struct dm_exception_store **store)
 {
        int r = 0;
-       struct dm_exception_store_type *type;
+       struct dm_exception_store_type *type = NULL;
        struct dm_exception_store *tmp_store;
        char persistent;
 
@@ -211,12 +211,15 @@ int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
        }
 
        persistent = toupper(*argv[1]);
-       if (persistent != 'P' && persistent != 'N') {
+       if (persistent == 'P')
+               type = get_type("P");
+       else if (persistent == 'N')
+               type = get_type("N");
+       else {
                ti->error = "Persistent flag is not P or N";
                return -EINVAL;
        }
 
-       type = get_type(&persistent);
        if (!type) {
                ti->error = "Exception store type not recognised";
                r = -EINVAL;