CVE-2024-40900
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2024-40900
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2024-40900.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2024-40900
- Downstream
- Related
- Published
- 2024-07-12T13:15:13Z
- Modified
- 2025-09-17T15:32:01Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- [none]
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
cachefiles: remove requests from xarray during flushing requests
Even with CACHEFILES_DEAD set, we can still read the requests, so in the following concurrency the request may be used after it has been freed:
mount | daemonthread1 | daemonthread2
cachefilesondemandinitobject cachefilesondemandsendreq REQA = kzalloc(sizeof(*req) + datalen) waitforcompletion(&REQA->done) cachefilesdaemonread cachefilesondemanddaemonread // close dev fd cachefilesflushreqs complete(&REQA->done) kfree(REQA) xalock(&cache->reqs); cachefilesondemandselectreq req->msg.opcode != CACHEFILESOPREAD // req use-after-free !!! xaunlock(&cache->reqs); xadestroy(&cache->reqs)
Hence remove requests from cache->reqs when flushing them to avoid accessing freed requests.
- References