dm-verity: disable recursive forward error correction
- 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- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean?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 5.15.209, 6.1.167, 6.6.130, 6.12.78, 6.18.6
- 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
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
In the Linux kernel, the following vulnerability has been resolved: dm-verity: disable recursive forward error correction There are two problems with the recursive correction: 1. It may cause denial-of-service. In fec_read_bufs, there is a loop that has 253 iterations. For each iteration, we may call verity_hash_for_block recursively. There is a limit of 4 nested recursions - that means that there may be at most 253^4 (4 billion) iterations. Red Hat QE team actually created an image that pushes dm-verity to this limit - and this image just makes the udev-worker process get stuck in the 'D' state. 2. It doesn't work. In fec_read_bufs we store data into the variable "fio->bufs", but fio bufs is shared between recursive invocations, if "verity_hash_for_block" invoked correction recursively, it would overwrite partially filled fio->bufs.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
From a739ff3f543afbb4a041c16cd0182c8e8d366e70 · fixed in 8b821ca892cfeeaf0bedc9fc72717294f67144d5; From a739ff3f543afbb4a041c16cd0182c8e8d366e70 · fixed in e227d2b229c7529bd98d348efc55262ccf24ab35; From a739ff3f543afbb4a041c16cd0182c8e8d366e70 · fixed in 897d9006e75f46f8bd7df78faa424327ae6a4bcf; From a739ff3f543afbb4a041c16cd0182c8e8d366e70 · fixed in 4220cb37406915c926c0e4a3dbab77cd9cceeb1e; From a739ff3f543afbb4a041c16cd0182c8e8d366e70 · fixed in 232948cf600fba69aff36b25d85ef91a73a35756; From a739ff3f543afbb4a041c16cd0182c8e8d366e70 · fixed in d9f3e47d3fae0c101d9094bc956ed24e7a0ee801
- Linux Linux
4.5
- KernelLinux
From 4.5.0 · fixed in 5.15.209; From 5.16.0 · fixed in 6.1.167; From 6.2.0 · fixed in 6.6.130; From 6.7.0 · fixed in 6.12.78; From 6.13.0 · fixed in 6.18.6