Commit 480f89d5 authored by Harshad Shirwadkar's avatar Harshad Shirwadkar Committed by Theodore Ts'o
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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: default avatarHarshad Shirwadkar <harshadshirwadkar@gmail.com>
Link: https://lore.kernel.org/r/20201106035911.1942128-13-harshadshirwadkar@gmail.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 0ee66ddc

fs/jbd2/journal.c

+4 −2
Original line number Diff line number Diff line
@@ -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);