diff options
| author | Theodore Ts'o <tytso@mit.edu> | 2018-06-16 20:21:45 -0400 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-07-11 16:03:48 +0200 |
| commit | 2cd33a53177ce739fe5f68052b2a737f1c40b425 (patch) | |
| tree | 73ca3c46b5a48e2d6325a6f443828dc3db8365c0 | |
| parent | 6ee6f1787e69db4b8b155450ca8694c145c2517c (diff) | |
jbd2: don't mark block as modified if the handle is out of credits
commit e09463f220ca9a1a1ecfda84fcda658f99a1f12a upstream.
Do not set the b_modified flag in block's journal head should not
until after we're sure that jbd2_journal_dirty_metadat() will not
abort with an error due to there not being enough space reserved in
the jbd2 handle.
Otherwise, future attempts to modify the buffer may lead a large
number of spurious errors and warnings.
This addresses CVE-2018-10883.
https://bugzilla.kernel.org/show_bug.cgi?id=200071
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | fs/jbd2/transaction.c | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/fs/jbd2/transaction.c b/fs/jbd2/transaction.c index f3a31f55f372..bce343febb9e 100644 --- a/fs/jbd2/transaction.c +++ b/fs/jbd2/transaction.c @@ -1363,6 +1363,13 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh) if (jh->b_transaction == transaction && jh->b_jlist != BJ_Metadata) { jbd_lock_bh_state(bh); + if (jh->b_transaction == transaction && + jh->b_jlist != BJ_Metadata) + pr_err("JBD2: assertion failure: h_type=%u " + "h_line_no=%u block_no=%llu jlist=%u\n", + handle->h_type, handle->h_line_no, + (unsigned long long) bh->b_blocknr, + jh->b_jlist); J_ASSERT_JH(jh, jh->b_transaction != transaction || jh->b_jlist == BJ_Metadata); jbd_unlock_bh_state(bh); @@ -1382,11 +1389,11 @@ int jbd2_journal_dirty_metadata(handle_t *handle, struct buffer_head *bh) * of the transaction. This needs to be done * once a transaction -bzzz */ - jh->b_modified = 1; if (handle->h_buffer_credits <= 0) { ret = -ENOSPC; goto out_unlock_bh; } + jh->b_modified = 1; handle->h_buffer_credits--; } |