CVE-2025-71304
Description
In the Linux kernel, the following vulnerability has been resolved: smack: /smack/doi: accept previously used values Writing to /smack/doi a value that has ever been written there in the past disables networking for non-ambient labels. E.g. # cat /smack/doi 3 # netlabelctl -p cipso list Configured CIPSO mappings (1) DOI value : 3 mapping type : PASS_THROUGH # netlabelctl -p map list Configured NetLabel domain mappings (3) domain: "_" (IPv4) protocol: UNLABELED domain: DEFAULT (IPv4) protocol: CIPSO, DOI = 3 domain: DEFAULT (IPv6) protocol: UNLABELED # cat /smack/ambient _ # cat /proc/$$/attr/smack/current _ # ping -c1 10.1.95.12 64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.964 ms # echo foo >/proc/$$/attr/smack/current # ping -c1 10.1.95.12 64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.956 ms unknown option 86 # echo 4 >/smack/doi # echo 3 >/smack/doi !> [ 214.050395] smk_cipso_doi:691 cipso add rc = -17 # echo 3 >/smack/doi !> [ 249.402261] smk_cipso_doi:678 remove rc = -2 !> [ 249.402261] smk_cipso_doi:691 cipso add rc = -17 # ping -c1 10.1.95.12 !!> ping: 10.1.95.12: Address family for hostname not supported # echo _ >/proc/$$/attr/smack/current # ping -c1 10.1.95.12 64 bytes from 10.1.95.12: icmp_seq=1 ttl=64 time=0.617 ms This happens because Smack keeps decommissioned DOIs, fails to re-add them, and consequently refuses to add the “default” domain map: # netlabelctl -p cipso list Configured CIPSO mappings (2) DOI value : 3 mapping type : PASS_THROUGH DOI value : 4 mapping type : PASS_THROUGH # netlabelctl -p map list Configured NetLabel domain mappings (2) domain: "_" (IPv4) protocol: UNLABELED !> (no ipv4 map for default domain here) domain: DEFAULT (IPv6) protocol: UNLABELED Fix by clearing decommissioned DOI definitions and serializing concurrent DOI updates with a new lock. Also: - allow /smack/doi to live unconfigured, since adding a map (netlbl_cfg_cipsov4_map_add) may fail. CIPSO_V4_DOI_UNKNOWN(0) indicates the unconfigured DOI - add new DOI before removing the old default map, so the old map remains if the add fails (2008-02-04, Casey Schaufler)
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.
✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here withsource_tier=community-verified.
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| debian | bookworm | fixed | 6.1.170-1 |
| debian | forky | fixed | 6.18.14-1 |
| debian | sid | fixed | 6.18.14-1 |
| debian | trixie | fixed | 6.12.85-1 |
| sles | affected | | |
| debian | bullseye | fixed | 5.10.257-1 |
References
- https://git.kernel.org/stable/c/eb718a3c8181ada679340db34cd61bce48e44749
- https://git.kernel.org/stable/c/6ec091c5c7eeabd249a7c46813cad1e9f555f859
- https://git.kernel.org/stable/c/199452f22d2f74b897fe826f81ec402b0a8461a0
- https://git.kernel.org/stable/c/1c7ee23dfcd18d80770d8f90f2ab5bb1b2bfd8a3
- https://git.kernel.org/stable/c/f8071500177f38cff38892bd85ac631cc6e010b2
- https://git.kernel.org/stable/c/5a247a84de0ba44edbbd6be851c8a6b2aa60ff85
- https://git.kernel.org/stable/c/8beebb8ad9a003f978e53b06237986588223e15e
- https://git.kernel.org/stable/c/33d589ed60ae433b483761987b85e0d24e54584e
- https://security-tracker.debian.org/tracker/CVE-2025-71304
- https://www.suse.com/security/cve/CVE-2025-71304.html
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.