CVE-2026-43374
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
08/05/2026
Última modificación:
08/05/2026
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
net: nexthop: fix percpu use-after-free in remove_nh_grp_entry<br />
<br />
When removing a nexthop from a group, remove_nh_grp_entry() publishes<br />
the new group via rcu_assign_pointer() then immediately frees the<br />
removed entry&#39;s percpu stats with free_percpu(). However, the<br />
synchronize_net() grace period in the caller remove_nexthop_from_groups()<br />
runs after the free. RCU readers that entered before the publish still<br />
see the old group and can dereference the freed stats via<br />
nh_grp_entry_stats_inc() -> get_cpu_ptr(nhge->stats), causing a<br />
use-after-free on percpu memory.<br />
<br />
Fix by deferring the free_percpu() until after synchronize_net() in the<br />
caller. Removed entries are chained via nh_list onto a local deferred<br />
free list. After the grace period completes and all RCU readers have<br />
finished, the percpu stats are safely freed.



