jbd2: Fail to load a journal if it is too short
Due to on disk corruption, it can happen that journal is too short. Fail
to load it in such case so that we don't oops somewhere later.
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c
index e378cb3..a8a358b 100644
--- a/fs/jbd2/journal.c
+++ b/fs/jbd2/journal.c
@@ -1187,6 +1187,12 @@
first = be32_to_cpu(sb->s_first);
last = be32_to_cpu(sb->s_maxlen);
+ if (first + JBD2_MIN_JOURNAL_BLOCKS > last + 1) {
+ printk(KERN_ERR "JBD: Journal too short (blocks %llu-%llu).\n",
+ first, last);
+ journal_fail_superblock(journal);
+ return -EINVAL;
+ }
journal->j_first = first;
journal->j_last = last;