null_blk: serialize configfs attribute stores with the lock
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 6.1.188, 6.6.157, 6.12.110, 6.18.52, 7.2.6
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
In the Linux kernel, the following vulnerability has been resolved: null_blk: serialize configfs attribute stores with the lock The NULLB_DEVICE_ATTR _store takes no lock: apply_fn attributes (submit_queues, poll_queues) get dev->NAME written again after apply_fn returns, outside its lock; APPLY=NULL attributes are entirely lockless. configfs only serializes stores per-open-file, so concurrent stores on separate fds race. For apply_fn attributes, once one store's apply_fn has reconfigured the hardware, a second (losing) store can still overwrite dev->NAME afterwards. This leaves dev->submit_queues out of sync with the live queue count, which is later caught by the WARN_ON_ONCE() in null_map_queues(). For !apply_fn attributes, power_store()'s null_add_dev() validates and builds the device under "lock" but only sets CONFIGURED afterwards. A store slipping in during this window can change a field mid-setup -- for example, zone_nr_conv can be pushed above nr_zones after it has already been clamped, leading to an out-of-bounds dev->zones[] access. Take "lock" in the macro around the apply_fn call, the CONFIGURED test and the field write, and move it out of nullb_apply_submit_queues()/ nullb_apply_poll_queues() so both paths are covered once. This serializes stores with power_store's setup and with each other.
Timeline
- CVE published
- Record last updated
Affected versions
- Linux Linux
From 45919fbfe1c487c17ea1d198534339a5e8abeae3 · fixed in 8e839ed5210399a0330a8a6c5885c1d40a537c6d; From 45919fbfe1c487c17ea1d198534339a5e8abeae3 · fixed in 88d806d0e1d36246208386a8e55b511c1b3d647c; From 45919fbfe1c487c17ea1d198534339a5e8abeae3 · fixed in 3945ce8cbce4e328e6fdf0b522dc71e340de19db; From 45919fbfe1c487c17ea1d198534339a5e8abeae3 · fixed in 65cae82fd3c39b53430672cb9e3ecd267471a6ce; From 45919fbfe1c487c17ea1d198534339a5e8abeae3 · fixed in c70994c2862b05e44728912b2ea9487d31e2aea7; From 45919fbfe1c487c17ea1d198534339a5e8abeae3 · fixed in 7e7fff51808237703a3a1df6dd5cae1dfd1db86d
- Linux Linux
5.5
- KernelLinux
From 5.5.0 · fixed in 6.1.188; From 6.2.0 · fixed in 6.6.157; From 6.7.0 · fixed in 6.12.110; From 6.13.0 · fixed in 6.18.52; From 6.19.0 · fixed in 7.2.6