CVE-2022-49995
Description
In the Linux kernel, the following vulnerability has been resolved: writeback: avoid use-after-free after removing device When a disk is removed, bdi_unregister gets called to stop further writeback and wait for associated delayed work to complete. However, wb_inode_writeback_end() may schedule bandwidth estimation dwork after this has completed, which can result in the timer attempting to access the just freed bdi_writeback. Fix this by checking if the bdi_writeback is alive, similar to when scheduling writeback work. Since this requires wb->work_lock, and wb_inode_writeback_end() may get called from interrupt, switch wb->work_lock to an irqsafe lock.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2022-49995
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2022-49995.html
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2023:2458
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 6.0.2-1 |
| debian | bullseye | fixed | 0 |
| debian | forky | fixed | 6.0.2-1 |
| debian | sid | fixed | 6.0.2-1 |
| debian | trixie | fixed | 6.0.2-1 |
References
Verify integrity in audit chain (admin only). AS-IS.