From c390087591dcbecd244c31d979ccdad49ae83364 Mon Sep 17 00:00:00 2001 From: "Darrick J. Wong" Date: Sun, 27 May 2012 08:12:12 -0400 Subject: 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 Signed-off-by: "Theodore Ts'o" --- fs/jbd2/recovery.c | 30 ++++++++++++++++++++++++++++++ 1 file changed, 30 insertions(+) (limited to 'fs/jbd2/recovery.c') diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c index df4a20e7d854..0131e4362534 100644 --- a/fs/jbd2/recovery.c +++ b/fs/jbd2/recovery.c @@ -393,6 +393,23 @@ static int jbd2_commit_block_csum_verify(journal_t *j, void *buf) 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 @@ static int do_one_pass(journal_t *journal, 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, -- cgit