jbd2: checksum data blocks that are stored in the journal
Calculate and verify checksums of each data block being stored in the journal.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c
index df4a20e..0131e43 100644
--- a/fs/jbd2/recovery.c
+++ b/fs/jbd2/recovery.c
@@ -393,6 +393,23 @@
return provided == calculated;
}
+static int jbd2_block_tag_csum_verify(journal_t *j, journal_block_tag_t *tag,
+ void *buf, __u32 sequence)
+{
+ __u32 provided, calculated;
+
+ if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2))
+ return 1;
+
+ sequence = cpu_to_be32(sequence);
+ calculated = jbd2_chksum(j, j->j_csum_seed, (__u8 *)&sequence,
+ sizeof(sequence));
+ calculated = jbd2_chksum(j, calculated, buf, j->j_blocksize);
+ provided = be32_to_cpu(tag->t_checksum);
+
+ return provided == cpu_to_be32(calculated);
+}
+
static int do_one_pass(journal_t *journal,
struct recovery_info *info, enum passtype pass)
{
@@ -569,6 +586,19 @@
goto skip_write;
}
+ /* Look for block corruption */
+ if (!jbd2_block_tag_csum_verify(
+ journal, tag, obh->b_data,
+ be32_to_cpu(tmp->h_sequence))) {
+ brelse(obh);
+ success = -EIO;
+ printk(KERN_ERR "JBD: Invalid "
+ "checksum recovering "
+ "block %llu in log\n",
+ blocknr);
+ continue;
+ }
+
/* Find a buffer for the new
* data being restored */
nbh = __getblk(journal->j_fs_dev,