kevin/linux
1
Fork 0
Code

ext4: fix incorrect tid assumption in ext4_fc_mark_ineligible()

Browse Source 
Function jbd2_journal_shrink_checkpoint_list() assumes that '0' is not a
valid value for transaction IDs, which is incorrect.

Furthermore, the sbi->s_fc_ineligible_tid handling also makes the same
assumption by being initialised to '0'.  Fortunately, the sb flag
EXT4_MF_FC_INELIGIBLE can be used to check whether sbi->s_fc_ineligible_tid
has been previously set instead of comparing it with '0'.

Signed-off-by: Luis Henriques (SUSE) <luis.henriques@linux.dev>
Reviewed-by: Jan Kara <jack@suse.cz>
Link: https://patch.msgid.link/20240724161119.13448-5-luis.henriques@linux.dev
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
This commit is contained in:
Luis Henriques (SUSE) 2024-07-24 17:11:18 +01:00 committed by Theodore Ts'o
parent 7a6443e1da
commit ebc4b2c1ac
1 changed files with 11 additions and 4 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

15
fs/ext4/fast_commit.c
View File

@ -339,22 +339,29 @@ void ext4_fc_mark_ineligible(struct super_block *sb, int reason, handle_t *handl
{
struct ext4_sb_info *sbi = EXT4_SB(sb);
tid_t tid;
bool has_transaction = true;
bool is_ineligible;
if (ext4_fc_disabled(sb))
return;
ext4_set_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
if (handle && !IS_ERR(handle))
tid = handle->h_transaction->t_tid;
else {
read_lock(&sbi->s_journal->j_state_lock);
tid = sbi->s_journal->j_running_transaction ?
sbi->s_journal->j_running_transaction->t_tid : 0;
if (sbi->s_journal->j_running_transaction)
tid = sbi->s_journal->j_running_transaction->t_tid;
else
has_transaction = false;
read_unlock(&sbi->s_journal->j_state_lock);
}
spin_lock(&sbi->s_fc_lock);
if (tid_gt(tid, sbi->s_fc_ineligible_tid))
is_ineligible = ext4_test_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
if (has_transaction &&
(!is_ineligible ||
(is_ineligible && tid_gt(tid, sbi->s_fc_ineligible_tid))))
sbi->s_fc_ineligible_tid = tid;
ext4_set_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
spin_unlock(&sbi->s_fc_lock);
WARN_ON(reason >= EXT4_FC_REASON_MAX);
sbi->s_fc_stats.fc_ineligible_reason_count[reason]++;