CVE-2026-98443
Beschrijving NL
In the Linux kernel, the following vulnerability has been resolved:
xfs: fix cursor and pointer handling when recovering iunlink buckets
LOLLM pointed out a bug in xlog_recover_iunlink_bucket:
1. We don't null out prev_ip after releasing it, which can lead to UAF
problems if the inodegc flush call in the loop fails. at which point I noticed even more bugs:
2. If the inodegc flush inside the loop fails, we also leak @ip. 3. We set prev_agino to agino having already advanced agino, which
results in inodes with i_prev_unlinked set to itself. 4. If we exit the bottom of the loop with prev_ip set, then prev_ip
aliases ip and we also set its i_prev_unlinked to itself. Bugs 3 and 4 introduce loops into the unlinked list, though these loops
don't surface because we immediately flush each unlinked inode after
loading it. Fix all of these issues.
Origineel (Engels) tonen
In the Linux kernel, the following vulnerability has been resolved:
xfs: fix cursor and pointer handling when recovering iunlink buckets
LOLLM pointed out a bug in xlog_recover_iunlink_bucket:
1. We don't null out prev_ip after releasing it, which can lead to UAF
problems if the inodegc flush call in the loop fails.
at which point I noticed even more bugs:
2. If the inodegc flush inside the loop fails, we also leak @ip.
3. We set prev_agino to agino having already advanced agino, which
results in inodes with i_prev_unlinked set to itself.
4. If we exit the bottom of the loop with prev_ip set, then prev_ip
aliases ip and we also set its i_prev_unlinked to itself.
Bugs 3 and 4 introduce loops into the unlinked list, though these loops
don't surface because we immediately flush each unlinked inode after
loading it.
Fix all of these issues.