ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD
In the Linux kernel, the following vulnerability has been resolved: ipv6: addrconf: bail out of dad_failure when state is no longer POSTDAD addrconf_dad_failure() transitions ifp->state from DAD to POSTDAD via addrconf_dad_end(), which drops ifp->lock on return. The lock is re-acquired after net_info_ratelimited(). A concurrent ipv6_del_addr() can take the lock in that window, set ifp->state to DEAD and run list_del_rcu(&ifp->if_list). addrconf_dad_failure() then overwrites DEAD with ERRDAD at errdad: and schedules a new dad_work. The work calls ipv6_del_addr() again, hitting the already-poisoned list entry: general protection fault: 0000 [#1] SMP NOPTI CPU: 4 PID: 217 Comm: kworker/4:1 Workqueue: ipv6_addrconf addrconf_dad_work RIP: 0010:ipv6_del_addr+0xe9/0x280 RAX: dead000000000122 Call Trace: addrconf_dad_stop+0x113/0x140 addrconf_dad_work+0x28c/0x430 process_one_work+0x1eb/0x3b0 worker_thread+0x4d/0x400 kthread+0x104/0x140 ret_from_fork+0x35/0x40 Fold the addrconf_dad_end() logic into addrconf_dad_failure() under a single ifp->lock critical section. The STABLE_PRIVACY branch temporarily drops ifp->lock around address regeneration, so at lock_errdad: verify the state is still POSTDAD before transitioning to ERRDAD; bail out otherwise to avoid overwriting a state set by another path while the lock was released.
CVE-2026-74398
Primary source · Revision 1
Imported from structured advisory data. Source references identify upstream records or fields; verify affected versions and your deployed configuration.
Security context
Source reference: cve:CVE-2026-74398
Linux
Source reference: /containers/cna/affected/0/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Linux
Source reference: /containers/cna/affected/1/product
- Affected versions
- Not stated in this record
- Fixed versions
- Not stated in this record
- Prerequisites
- Not stated in this record
Structured affected-version data
Original package identities and version rules from this source.
[
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "47b05836705b63dab93d9ac7c69a3a507375ef80",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "d21be7d051012c6b572fa4e3334443c250216f7b",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "875c284c0f98b042bb97abad460f63a24c977f88",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "8ed0ce9ea58d677d1bac92614ee5f60f8ea57363",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "3bdc86d89fd6c6523753fa6f42fcfaf30ee699cb",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "b61af0268e3d1308c466bf0be5dced844eafc1ef",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "e889aa99ad3ed48bb0ddcff6475b17542532d18b",
"versionType": "git"
},
{
"status": "affected",
"version": "c15b1ccadb323ea50023e8f1cca2954129a62b51",
"lessThan": "627ac78f2741e2ebd2225e2e953b6964a8a9182f",
"versionType": "git"
},
{
"status": "affected",
"version": "835b474b8f70fa68d68abffad37378e92f661802",
"versionType": "git"
},
{
"status": "affected",
"version": "3.10.105",
"lessThan": "3.11",
"versionType": "semver"
}
],
"programFiles": [
"net/ipv6/addrconf.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "3.14"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "3.14",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.261",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.212",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.178",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.145",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.97",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.40",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "7.1.5",
"versionType": "semver",
"lessThanOrEqual": "7.1.*"
},
{
"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/ipv6/addrconf.c"
],
"defaultStatus": "affected"
}
]- Related CVEs
- CVE-2026-74398
Source reference:
/cveMetadata/cveId
Publisher severity
critical
Source reference: /containers/cna/metrics
- Event
- #33139 · Revision 1
- Added to Heist Feed
- Publisher date