FKIE_CVE-2026-23124
Vulnerability from fkie_nvd - Published: 2026-02-14 15:16 - Updated: 2026-02-18 17:52
Severity ?
Summary
In the Linux kernel, the following vulnerability has been resolved:
ipv6: annotate data-race in ndisc_router_discovery()
syzbot found that ndisc_router_discovery() could read and write
in6_dev->ra_mtu without holding a lock [1]
This looks fine, IFLA_INET6_RA_MTU is best effort.
Add READ_ONCE()/WRITE_ONCE() to document the race.
Note that we might also reject illegal MTU values
(mtu < IPV6_MIN_MTU || mtu > skb->dev->mtu) in a future patch.
[1]
BUG: KCSAN: data-race in ndisc_router_discovery / ndisc_router_discovery
read to 0xffff888119809c20 of 4 bytes by task 25817 on cpu 1:
ndisc_router_discovery+0x151d/0x1c90 net/ipv6/ndisc.c:1558
ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841
icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989
ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438
ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489
NF_HOOK include/linux/netfilter.h:318 [inline]
ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500
ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590
dst_input include/net/dst.h:474 [inline]
ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79
...
write to 0xffff888119809c20 of 4 bytes by task 25816 on cpu 0:
ndisc_router_discovery+0x155a/0x1c90 net/ipv6/ndisc.c:1559
ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841
icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989
ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438
ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489
NF_HOOK include/linux/netfilter.h:318 [inline]
ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500
ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590
dst_input include/net/dst.h:474 [inline]
ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79
...
value changed: 0x00000000 -> 0xe5400659
References
Impacted products
| Vendor | Product | Version |
|---|
{
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nipv6: annotate data-race in ndisc_router_discovery()\n\nsyzbot found that ndisc_router_discovery() could read and write\nin6_dev-\u003era_mtu without holding a lock [1]\n\nThis looks fine, IFLA_INET6_RA_MTU is best effort.\n\nAdd READ_ONCE()/WRITE_ONCE() to document the race.\n\nNote that we might also reject illegal MTU values\n(mtu \u003c IPV6_MIN_MTU || mtu \u003e skb-\u003edev-\u003emtu) in a future patch.\n\n[1]\nBUG: KCSAN: data-race in ndisc_router_discovery / ndisc_router_discovery\n\nread to 0xffff888119809c20 of 4 bytes by task 25817 on cpu 1:\n ndisc_router_discovery+0x151d/0x1c90 net/ipv6/ndisc.c:1558\n ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841\n icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989\n ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438\n ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489\n NF_HOOK include/linux/netfilter.h:318 [inline]\n ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500\n ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590\n dst_input include/net/dst.h:474 [inline]\n ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79\n...\n\nwrite to 0xffff888119809c20 of 4 bytes by task 25816 on cpu 0:\n ndisc_router_discovery+0x155a/0x1c90 net/ipv6/ndisc.c:1559\n ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841\n icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989\n ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438\n ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489\n NF_HOOK include/linux/netfilter.h:318 [inline]\n ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500\n ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590\n dst_input include/net/dst.h:474 [inline]\n ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79\n...\n\nvalue changed: 0x00000000 -\u003e 0xe5400659"
},
{
"lang": "es",
"value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nipv6: anotar condici\u00f3n de carrera de datos en ndisc_router_discovery()\n\nsyzbot encontr\u00f3 que ndisc_router_discovery() pod\u00eda leer y escribir in6_dev-\u0026gt;ra_mtu sin mantener un bloqueo [1]\n\nEsto parece estar bien, IFLA_INET6_RA_MTU es de mejor esfuerzo.\n\nA\u00f1adir READ_ONCE()/WRITE_ONCE() para documentar la condici\u00f3n de carrera.\n\nTenga en cuenta que tambi\u00e9n podr\u00edamos rechazar valores MTU ilegales (mtu \u0026lt; IPV6_MIN_MTU || mtu \u0026gt; skb-\u0026gt;dev-\u0026gt;mtu) en un parche futuro.\n\n[1]\nERROR: KCSAN: condici\u00f3n de carrera de datos en ndisc_router_discovery / ndisc_router_discovery\n\nlectura a 0xffff888119809c20 de 4 bytes por la tarea 25817 en la cpu 1:\n ndisc_router_discovery+0x151d/0x1c90 net/ipv6/ndisc.c:1558\n ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841\n icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989\n ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438\n ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489\n NF_HOOK include/linux/netfilter.h:318 [inline]\n ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500\n ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590\n dst_input include/net/dst.h:474 [inline]\n ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79\n...\n\nescritura a 0xffff888119809c20 de 4 bytes por la tarea 25816 en la cpu 0:\n ndisc_router_discovery+0x155a/0x1c90 net/ipv6/ndisc.c:1559\n ndisc_rcv+0x2ad/0x3d0 net/ipv6/ndisc.c:1841\n icmpv6_rcv+0xe5a/0x12f0 net/ipv6/icmp.c:989\n ip6_protocol_deliver_rcu+0xb2a/0x10d0 net/ipv6/ip6_input.c:438\n ip6_input_finish+0xf0/0x1d0 net/ipv6/ip6_input.c:489\n NF_HOOK include/linux/netfilter.h:318 [inline]\n ip6_input+0x5e/0x140 net/ipv6/ip6_input.c:500\n ip6_mc_input+0x27c/0x470 net/ipv6/ip6_input.c:590\n dst_input include/net/dst.h:474 [inline]\n ip6_rcv_finish+0x336/0x340 net/ipv6/ip6_input.c:79\n...\n\nvalor cambiado: 0x00000000 -\u0026gt; 0xe5400659"
}
],
"id": "CVE-2026-23124",
"lastModified": "2026-02-18T17:52:44.520",
"metrics": {},
"published": "2026-02-14T15:16:07.633",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/2619499169fb1c2ac4974b0f2d87767fb543582b"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/2a2b9d25f801afecf2f83cacce98afa8fd73e3c9"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/4630897eb1a039b5d7b737b8dc9521d9d4b568b5"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/9a063f96d87efc3a6cc667f8de096a3d38d74bb5"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/e3c1040252e598f7b4e33a42dc7c38519bc22428"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/fad8f4ff7928f4d52a062ffdcffa484989c79c47"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Awaiting Analysis"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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