CVE-2026-98026 (GCVE-0-2026-98026)

Vulnerability from cvelistv5 – Published: 2026-09-25 10:23 – Updated: 2026-10-19 09:12
VLAI
Title
net: bridge: mcast: properly convert mglist to rcu
Summary
In the Linux kernel, the following vulnerability has been resolved: net: bridge: mcast: properly convert mglist to rcu Sashiko reported a bug [1] that br_multicast_del_port_group unlists the port group not using proper rcu helper that preserves the next pointer and after that immediately frees the port group without waiting for rcu grace period. The only rcu walker of mglist is br_multicast_list_adjacent() and it turns out that function has always been buggy because mglist was never properly converted to RCU. Fix it by converting it to rcu and moving its initialization after eth_addr's. Initializing p->next can use RCU_INIT_POINTER because we have a barrier from the hlist_add_head_rcu call later, besides we're initializing an unpublished structure anyway. [1] https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20260826014200.362304-1-littleddfu%40gmail.com
Severity
No CVSS data available.
Assigner
Linux CNA under the mitre root
CNA scorecard D 53/100 over 6856 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 , < 37cb9a81600da8250f24e25edc07253b62353cbe (git)
Affected: 07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 , < 98247c8264d2076f81fa114bdfa2c2271953ac7c (git)
Affected: 07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 , < 38ab2a435001a3c4dbeb70a52f5921e1ccd66f55 (git)
Affected: 07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 , < f7bf57e94a5d6214b87be08486cb33836fbfa573 (git)
Affected: 07f8ac4a1e26e8283542cdaf658a6e2a12fd6980 , < 4b772869a1e5f9da5cef5b9c722ec0aa424ee0a0 (git)
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Linux Linux Affected: 3.16
Unaffected: 0 , < 3.16 (semver)
Unaffected: 6.6.158 , ≤ 6.6.* (semver)
Unaffected: 6.12.111 , ≤ 6.12.* (semver)
Unaffected: 6.18.53 , ≤ 6.18.* (semver)
Unaffected: 7.2.7 , ≤ 7.2.* (semver)
Unaffected: 7.3 , ≤ * (original_commit_for_fix)
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Show details on NVD website
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{
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          "programFiles": [
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    "datePublished": "2026-09-25T10:23:44.505Z",
    "dateReserved": "2026-09-25T10:19:56.070Z",
    "dateUpdated": "2026-10-19T09:12:31.334Z",
    "state": "PUBLISHED"
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      "product_status:known_affected": "1",
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}



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