mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
synced 2026-07-24 02:09:13 -04:00
425e30577f
Initially, a dedicated workqueue was used to defer calling udp_tunnel_sock_release(vxlan_sock->sock) and kfree(vxlan_sock). Later, commit0412bd931f("vxlan: synchronously and race-free destruction of vxlan sockets") removed the workqueue and instead invoked these two functions immediately after synchronize_net(). This was intended to prevent UAF of the UDP socket in the fast path. ( Note that the "nondeterministic behaviour" mentioned in that commit was not addressed, as another thread not waiting RCU gp still sees the same behaviour. ) However, a week prior to that change, commitca065d0cf8("udp: no longer use SLAB_DESTROY_BY_RCU") had already moved UDP socket freeing to after the RCU grace period. This made the synchronize_net() in vxlan_sock_release() completely redundant. Since vxlan_sock now uses kfree_rcu() and is invoked after udp_tunnel_sock_release(), vxlan_sock is guaranteed to be freed either at the same time or after the UDP socket is released, following the RCU grace period. Let's remove the redundant synchronize_net() in vxlan_sock_release(). Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com> Link: https://patch.msgid.link/20260518050726.318824-2-kuniyu@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>