This is a note to let you know that I've just added the patch titled
ext4: fix possible tid_t sequence overflows
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ext4-fix-possible-tid_t-sequence-overflows.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit bc02f8286b4d4f9409bf9329ed8310b981f79463
Author: Luis Henriques (SUSE) <luis.henriques@xxxxxxxxx>
Date: Wed May 29 10:20:30 2024 +0100
ext4: fix possible tid_t sequence overflows
[ Upstream commit 63469662cc45d41705f14b4648481d5d29cf5999 ]
In the fast commit code there are a few places where tid_t variables are
being compared without taking into account the fact that these sequence
numbers may wrap. Fix this issue by using the helper functions tid_gt()
and tid_geq().
Signed-off-by: Luis Henriques (SUSE) <luis.henriques@xxxxxxxxx>
Reviewed-by: Jan Kara <jack@xxxxxxx>
Reviewed-by: Harshad Shirwadkar <harshadshirwadkar@xxxxxxxxx>
Link: https://patch.msgid.link/20240529092030.9557-3-luis.henriques@xxxxxxxxx
Signed-off-by: Theodore Ts'o <tytso@xxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/fs/ext4/fast_commit.c b/fs/ext4/fast_commit.c
index e81b886d9c67..62255b3eb1b4 100644
--- a/fs/ext4/fast_commit.c
+++ b/fs/ext4/fast_commit.c
@@ -325,7 +325,7 @@ void ext4_fc_mark_ineligible(struct super_block *sb, int reason, handle_t *handl
read_unlock(&sbi->s_journal->j_state_lock);
}
spin_lock(&sbi->s_fc_lock);
- if (sbi->s_fc_ineligible_tid < tid)
+ if (tid_gt(tid, sbi->s_fc_ineligible_tid))
sbi->s_fc_ineligible_tid = tid;
spin_unlock(&sbi->s_fc_lock);
WARN_ON(reason >= EXT4_FC_REASON_MAX);
@@ -1206,7 +1206,7 @@ int ext4_fc_commit(journal_t *journal, tid_t commit_tid)
if (ret == -EALREADY) {
/* There was an ongoing commit, check if we need to restart */
if (atomic_read(&sbi->s_fc_subtid) <= subtid &&
- commit_tid > journal->j_commit_sequence)
+ tid_gt(commit_tid, journal->j_commit_sequence))
goto restart_fc;
ext4_fc_update_stats(sb, EXT4_FC_STATUS_SKIPPED, 0, 0);
return 0;
@@ -1278,7 +1278,7 @@ static void ext4_fc_cleanup(journal_t *journal, int full, tid_t tid)
list_del_init(&iter->i_fc_list);
ext4_clear_inode_state(&iter->vfs_inode,
EXT4_STATE_FC_COMMITTING);
- if (iter->i_sync_tid <= tid)
+ if (tid_geq(tid, iter->i_sync_tid))
ext4_fc_reset_inode(&iter->vfs_inode);
/* Make sure EXT4_STATE_FC_COMMITTING bit is clear */
smp_mb();
@@ -1308,7 +1308,7 @@ static void ext4_fc_cleanup(journal_t *journal, int full, tid_t tid)
list_splice_init(&sbi->s_fc_q[FC_Q_STAGING],
&sbi->s_fc_q[FC_Q_MAIN]);
- if (tid >= sbi->s_fc_ineligible_tid) {
+ if (tid_geq(tid, sbi->s_fc_ineligible_tid)) {
sbi->s_fc_ineligible_tid = 0;
ext4_clear_mount_flag(sb, EXT4_MF_FC_INELIGIBLE);
}
