CVE-2024-49854 (GCVE-0-2024-49854)
Vulnerability from cvelistv5
Published
2024-10-21 12:18
Modified
2026-08-05 11:40
Severity ?
7.8 (High) - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Summary
In the Linux kernel, the following vulnerability has been resolved: block, bfq: fix uaf for accessing waker_bfqq after splitting After commit 42c306ed7233 ("block, bfq: don't break merge chain in bfq_split_bfqq()"), if the current procress is the last holder of bfqq, the bfqq can be freed after bfq_split_bfqq(). Hence recored the bfqq and then access bfqq->waker_bfqq may trigger UAF. What's more, the waker_bfqq may in the merge chain of bfqq, hence just recored waker_bfqq is still not safe. Fix the problem by adding a helper bfq_waker_bfqq() to check if bfqq->waker_bfqq is in the merge chain, and current procress is the only holder.
References
Impacted products
Vendor Product Version
Linux Linux Version: e0c20d88b7dce85d2703bb6ba77bf359959675cd
Version: de6c5e3a456019d2182e345730e59721714fa0b5
Version: 19f3bec2ac4be329b9bd12b18a989b867618d2d8
Version: 13b3d0e8cb121f99b11918a0d4bcc1ce4647d352
Version: 4780f50ea50cfe8e89fc3747bf3dd155488433bb
Version: 42c306ed723321af4003b2a41bb73728cab54f85
Version: 9e813033594b141f61ff0ef0cfaaef292564b041
Version: 3a5f45a4ad4e1fd36b0a998eef03d76a4f02a2a8
Version: 3630a18846c7853aa326d3b42fd0a855af7b41bc
Version: 4.19.323   ≤
Version: 5.4.285   ≤
Version: 5.10.227   ≤
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