jbd2: invalidate handle if jbd2_journal_restart() fails

If jbd2_journal_restart() fails the handle will have been disconnected
from the current transaction.  In this situation, the handle must not
be used for for any jbd2 function other than jbd2_journal_stop().
Enforce this with by treating a handle which has a NULL transaction
pointer as an aborted handle, and issue a kernel warning if
jbd2_journal_extent(), jbd2_journal_get_write_access(),
jbd2_journal_dirty_metadata(), etc. is called with an invalid handle.

This commit also fixes a bug where jbd2_journal_stop() would trip over
a kernel jbd2 assertion check when trying to free an invalid handle.

Also move the responsibility of setting current->journal_info to
start_this_handle(), simplifying the three users of this function.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Reported-by: Younger Liu <younger.liu@huawei.com>
Cc: Jan Kara <jack@suse.cz>

1 files changed, 1 insertions, 1 deletions

diff --git a/include/linux/jbd2.h b/include/linux/jbd2.h
index 0302f3f14063..d5b50a19463c 100644
--- a/include/linux/jbd2.h
+++ b/include/linux/jbd2.h
@@ -1266,7 +1266,7 @@ static inline int is_journal_aborted(journal_t *journal)
 
 static inline int is_handle_aborted(handle_t *handle)
 {
-        if (handle->h_aborted)
+        if (handle->h_aborted || !handle->h_transaction)
                 return 1;
         return is_journal_aborted(handle->h_transaction->t_journal);
 }