In the Linux kernel, the following vulnerability has been resolved:
libceph: remove debugfs files before client teardown
ceph_destroy_client() tears down the monitor client before removing the per-client debugfs files. A concurrent read of the monmap debugfs file can enter monmap_show() after ceph_monc_stop() has freed monc->monmap, triggering a use-after-free.
Remove the debugfs files before stopping the OSD and monitor clients. debugfs_remove() drains active handlers and prevents new accesses, so the debugfs callbacks can no longer race the rest of client teardown.
References
- https://git.kernel.org/stable/c/8f5a3abc54ba24dbceb14cc3a719908c4f688091
- https://git.kernel.org/stable/c/b9fedda2f628e030384228de0dafc574b7fb0c2f
- https://git.kernel.org/stable/c/d3dc8889d39a676bf840132bd5c5c48cb0daba23
- https://git.kernel.org/stable/c/e4c804726c4afce3ba648b982d564f6af2cfa328
- https://git.kernel.org/stable/c/fc1010e7e0204ece6cc0f9af4f473e9553535eab