CVE-2026-97599ieee802154: hwsim: serialize pib updates to fix double-free

Official description

In the Linux kernel, the following vulnerability has been resolved: ieee802154: hwsim: serialize pib updates to fix double-free hwsim_update_pib() does an unserialized read-swap-free of phy->pib: pib_old = rtnl_dereference(phy->pib); ... rcu_assign_pointer(phy->pib, pib); kfree_rcu(pib_old, rcu); It assumes the RTNL is held, but ->set_channel is not always called under it: the mac802154 scan worker changes channels via drv_set_channel() without the RTNL. Such an update can race an RTNL-held one on the same phy; both read the same pib_old and both kfree_rcu() it, double-freeing the object. With SLUB percpu sheaves batching kfree_rcu(), this surfaces as a KASAN invalid-free in rcu_free_sheaf(). struct hwsim_phy has no lock for pib. Add one and make the swap atomic with rcu_replace_pointer() under it, dropping the misleading rtnl_dereference().

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/8f44a61f816581c35c1974c8c1a3b3c2c49e96be
• https://git.kernel.org/stable/c/e3b4681197aa026bd2d79358de5a3d62b76b04b9
• https://git.kernel.org/stable/c/9973b3a67a7592a780ea12b08334539a900deec1
• https://git.kernel.org/stable/c/d3b8f264ce09573aededd0a97dc41c8147797d8f
• https://git.kernel.org/stable/c/db6442deecb1f13aeaf4f9d77746ea7555630fb3
• https://git.kernel.org/stable/c/979d5b8de8ed4e1f997aef12da5694b99be7b871