CVE-2024-40909 (GCVE-0-2024-40909)
Vulnerability from cvelistv5
Published
2024-07-12 12:20
Modified
2026-08-05 11:33
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: bpf: Fix a potential use-after-free in bpf_link_free() After commit 1a80dbcb2dba, bpf_link can be freed by link->ops->dealloc_deferred, but the code still tests and uses link->ops->dealloc afterward, which leads to a use-after-free as reported by syzbot. Actually, one of them should be sufficient, so just call one of them instead of both. Also add a WARN_ON() in case of any problematic implementation.
References
Impacted products
Vendor Product Version
Linux Linux Version: 876941f533e7b47fc69977fc4551c02f2d18af97
Version: 1a80dbcb2dbaf6e4c216e62e30fa7d3daa8001ce
Version: 1a80dbcb2dbaf6e4c216e62e30fa7d3daa8001ce
Version: 5d8d447777564b35f67000e7838e7ccb64d525c8
Version: 6.6.26   ≤
Version: 6.8.5   ≤
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