On Wed 10-08-22 09:34:42, Ye Bin wrote: > As https://github.com/tytso/e2fsprogs/issues/120 describe tune2fs do not update > j_tail_sequence when do journal recovery. This maybe recover old journal record, > then will lead to file system corruption. > To avoid file system corruption in this case, if detect current transaction's > commit time earlier than previous transaction's commit time when do journal > scan, just return error. > > Signed-off-by: Ye Bin <yebin10@xxxxxxxxxx> Thanks for the patch! Let me see if I understand your concern right. You are concerned about the following scenario: 1) Kernel uses the filesystem, there's a crash. 2) E2fsprogs replays the journal but fails to update sb->s_sequence in the journal superblock. 3) Kernel mounts the fs again - however note that even if kernel skips recovery, it does scan the journal jbd2_journal_skip_recovery() and journal->j_transaction_sequence is set based on the last transaction found in the journal. So I don't think there is really possibility we will quickly reuse some transaction IDs and thus possibility of corruption on replay? Am I missing something? Honza > --- > fs/jbd2/recovery.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > > diff --git a/fs/jbd2/recovery.c b/fs/jbd2/recovery.c > index f548479615c6..f3def21a96a5 100644 > --- a/fs/jbd2/recovery.c > +++ b/fs/jbd2/recovery.c > @@ -812,8 +812,17 @@ static int do_one_pass(journal_t *journal, > break; > } > } > - if (pass == PASS_SCAN) > + if (pass == PASS_SCAN) { > + if (commit_time < last_trans_commit_time) { > + pr_err("JBD2: old journal record found " > + "in transaction %u\n", > + next_commit_ID); > + err = -EFSBADCRC; > + brelse(bh); > + goto failed; > + } > last_trans_commit_time = commit_time; > + } > brelse(bh); > next_commit_ID++; > continue; > -- > 2.31.1 > -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
