In the Linux kernel, the following vulnerability has been resolved:
net: nexthop: fix percpu use-after-free in remove_nh_grp_entry
When removing a nexthop from a group, remove_nh_grp_entry() publishes
the new group via rcu_assign_pointer() then immediately frees the
removed entry's percpu stats with free_percpu(). However, the
synchronize_net() grace period in the caller remove_nexthop_from_groups()
runs after the free. RCU readers that entered before the publish still
see the old group and can dereference the freed stats via
nh_grp_entry_stats_inc() -> get_cpu_ptr(nhge->stats), causing a
use-after-free on percpu memory.
Fix by deferring the free_percpu() until after synchronize_net() in the
caller. Removed entries are chained via nh_list onto a local deferred
free list. After the grace period completes and all RCU readers have
finished, the percpu stats are safely freed.
References
Configurations
Configuration 1 (hide)
|
History
No history.
Information
Published : 2026-05-08 15:16
Updated : 2026-06-17 10:49
NVD link : CVE-2026-43374
Mitre link : CVE-2026-43374
CVE.ORG link : CVE-2026-43374
JSON object : View
Products Affected
linux
- linux_kernel
CWE
CWE-416
Use After Free
