From 480f89d553260e7823920e687846877bebc8dca0 Mon Sep 17 00:00:00 2001 From: Harshad Shirwadkar Date: Thu, 5 Nov 2020 19:59:01 -0800 Subject: [PATCH] jbd2: don't read journal->j_commit_sequence without taking a lock Take journal state lock before reading journal->j_commit_sequence. Signed-off-by: Harshad Shirwadkar Link: https://lore.kernel.org/r/20201106035911.1942128-13-harshadshirwadkar@gmail.com Signed-off-by: Theodore Ts'o --- fs/jbd2/journal.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/fs/jbd2/journal.c b/fs/jbd2/journal.c index b5fbcd1b444c..f7ebf6ef69af 100644 --- a/fs/jbd2/journal.c +++ b/fs/jbd2/journal.c @@ -734,10 +734,12 @@ int jbd2_fc_begin_commit(journal_t *journal, tid_t tid) if (!journal->j_stats.ts_tid) return -EINVAL; - if (tid <= journal->j_commit_sequence) + write_lock(&journal->j_state_lock); + if (tid <= journal->j_commit_sequence) { + write_unlock(&journal->j_state_lock); return -EALREADY; + } - write_lock(&journal->j_state_lock); if (journal->j_flags & JBD2_FULL_COMMIT_ONGOING || (journal->j_flags & JBD2_FAST_COMMIT_ONGOING)) { DEFINE_WAIT(wait); -- 2.39.5