diff options
| -rw-r--r-- | fs/jbd2/commit.c | 25 | ||||
| -rw-r--r-- | fs/jbd2/recovery.c | 37 |
2 files changed, 60 insertions, 2 deletions
diff --git a/fs/jbd2/commit.c b/fs/jbd2/commit.c index 69d780310aea..5d505cfd21c2 100644 --- a/fs/jbd2/commit.c +++ b/fs/jbd2/commit.c @@ -301,6 +301,24 @@ static void write_tag_block(int tag_bytes, journal_block_tag_t *tag, tag->t_blocknr_high = cpu_to_be32((block >> 31) >> 1); } +static void jbd2_descr_block_csum_set(journal_t *j, + struct journal_head *descriptor) +{ + struct jbd2_journal_block_tail *tail; + __u32 csum; + + if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) + return; + + tail = (struct jbd2_journal_block_tail *) + (jh2bh(descriptor)->b_data + j->j_blocksize - + sizeof(struct jbd2_journal_block_tail)); + tail->t_checksum = 0; + csum = jbd2_chksum(j, j->j_csum_seed, jh2bh(descriptor)->b_data, + j->j_blocksize); + tail->t_checksum = cpu_to_be32(csum); +} + /* * jbd2_journal_commit_transaction * @@ -334,6 +352,10 @@ void jbd2_journal_commit_transaction(journal_t *journal) unsigned long first_block; tid_t first_tid; int update_tail; + int csum_size = 0; + + if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) + csum_size = sizeof(struct jbd2_journal_block_tail); /* * First job: lock down the current transaction and wait for @@ -643,7 +665,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) if (bufs == journal->j_wbufsize || commit_transaction->t_buffers == NULL || - space_left < tag_bytes + 16) { + space_left < tag_bytes + 16 + csum_size) { jbd_debug(4, "JBD2: Submit %d IOs\n", bufs); @@ -653,6 +675,7 @@ void jbd2_journal_commit_transaction(journal_t *journal) tag->t_flags |= cpu_to_be16(JBD2_FLAG_LAST_TAG); + jbd2_descr_block_csum_set(journal, descriptor); start_journal_io: for (i = 0; i < bufs; i++) { struct buffer_head *bh = wbuf[i]; diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c index 728ecd0705d9..066ee603db50 100644 --- a/fs/jbd2/recovery.c +++ b/fs/jbd2/recovery.c @@ -174,6 +174,25 @@ static int jread(struct buffer_head **bhp, journal_t *journal, return 0; } +static int jbd2_descr_block_csum_verify(journal_t *j, + void *buf) +{ + struct jbd2_journal_block_tail *tail; + __u32 provided, calculated; + + if (!JBD2_HAS_INCOMPAT_FEATURE(j, JBD2_FEATURE_INCOMPAT_CSUM_V2)) + return 1; + + tail = (struct jbd2_journal_block_tail *)(buf + j->j_blocksize - + sizeof(struct jbd2_journal_block_tail)); + provided = tail->t_checksum; + tail->t_checksum = 0; + calculated = jbd2_chksum(j, j->j_csum_seed, buf, j->j_blocksize); + tail->t_checksum = provided; + + provided = be32_to_cpu(provided); + return provided == calculated; +} /* * Count the number of in-use tags in a journal descriptor block. @@ -186,6 +205,9 @@ static int count_tags(journal_t *journal, struct buffer_head *bh) int nr = 0, size = journal->j_blocksize; int tag_bytes = journal_tag_bytes(journal); + if (JBD2_HAS_INCOMPAT_FEATURE(journal, JBD2_FEATURE_INCOMPAT_CSUM_V2)) + size -= sizeof(struct jbd2_journal_block_tail); + tagp = &bh->b_data[sizeof(journal_header_t)]; while ((tagp - bh->b_data + tag_bytes) <= size) { @@ -366,6 +388,7 @@ static int do_one_pass(journal_t *journal, int blocktype; int tag_bytes = journal_tag_bytes(journal); __u32 crc32_sum = ~0; /* Transactional Checksums */ + int descr_csum_size = 0; /* * First thing is to establish what we expect to find in the log @@ -451,6 +474,18 @@ static int do_one_pass(journal_t *journal, switch(blocktype) { case JBD2_DESCRIPTOR_BLOCK: + /* Verify checksum first */ + if (JBD2_HAS_INCOMPAT_FEATURE(journal, + JBD2_FEATURE_INCOMPAT_CSUM_V2)) + descr_csum_size = + sizeof(struct jbd2_journal_block_tail); + if (descr_csum_size > 0 && + !jbd2_descr_block_csum_verify(journal, + bh->b_data)) { + err = -EIO; + goto failed; + } + /* If it is a valid descriptor block, replay it * in pass REPLAY; if journal_checksums enabled, then * calculate checksums in PASS_SCAN, otherwise, @@ -481,7 +516,7 @@ static int do_one_pass(journal_t *journal, tagp = &bh->b_data[sizeof(journal_header_t)]; while ((tagp - bh->b_data + tag_bytes) - <= journal->j_blocksize) { + <= journal->j_blocksize - descr_csum_size) { unsigned long io_block; tag = (journal_block_tag_t *) tagp; |