From 4ac7b43e4e8488806e0e7deb03496037e79bb3cb Mon Sep 17 00:00:00 2001 From: "Luis Henriques (SUSE)" Date: Wed, 29 May 2024 10:20:30 +0100 Subject: [PATCH] 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) Reviewed-by: Jan Kara Reviewed-by: Harshad Shirwadkar Link: https://patch.msgid.link/20240529092030.9557-3-luis.henriques@linux.dev Signed-off-by: Theodore Ts'o Signed-off-by: Sasha Levin --- fs/ext4/fast_commit.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) 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 @@ restart_fc: 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); }