In the Linux kernel, the following vulnerability has been resolved:
ipv6: fix NULL pointer deref in ip6_rt_get_dev_rcu()
l3mdev_master_dev_rcu() can return NULL when the slave device is being
un-slaved from a VRF. All other callers deal with this, but we lost
the fallback to loopback in ip6_rt_pcpu_alloc() -> ip6_rt_get_dev_rcu()
with commit 4832c30d5458 ("net: ipv6: put host and anycast routes on
device with address").
KASAN: null-ptr-deref in range [0x0000000000000108-0x000000000000010f]
RIP: 0010:ip6_rt_pcpu_alloc (net/ipv6/route.c:1418)
Call Trace:
ip6_pol_route (net/ipv6/route.c:2318)
fib6_rule_lookup (net/ipv6/fib6_rules.c:115)
ip6_route_output_flags (net/ipv6/route.c:2607)
vrf_process_v6_outbound (drivers/net/vrf.c:437)
I was tempted to rework the un-slaving code to clear the flag first
and insert synchronize_rcu() before we remove the upper. But looks like
the explicit fallback to loopback_dev is an established pattern.
And I guess avoiding the synchronize_rcu() is nice, too.
References
Configurations
Configuration 1 (hide)
|
History
No history.
Information
Published : 2026-03-25 11:16
Updated : 2026-07-14 13:18
NVD link : CVE-2026-23304
Mitre link : CVE-2026-23304
CVE.ORG link : CVE-2026-23304
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-476
NULL Pointer Dereference
