CVE-2025-71161 (GCVE-0-2025-71161)
Vulnerability from cvelistv5
Published
2026-01-23 15:23
Modified
2026-08-05 12:12
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
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.
References
Impacted products
Vendor Product Version
Linux Linux Version: a739ff3f543afbb4a041c16cd0182c8e8d366e70
Version: a739ff3f543afbb4a041c16cd0182c8e8d366e70
Version: a739ff3f543afbb4a041c16cd0182c8e8d366e70
Version: a739ff3f543afbb4a041c16cd0182c8e8d366e70
Version: a739ff3f543afbb4a041c16cd0182c8e8d366e70
Version: a739ff3f543afbb4a041c16cd0182c8e8d366e70
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