In the Linux kernel, the following vulnerability has been resolved:
vxlan: Fix potential null-ptr-deref in vxlan_gro_prepare_receive().
udp_tunnel_sock_release() could set sk->sk_user_data to NULL while vxlan_gro_prepare_receive() is running.
Lets check if rcu_dereference_sk_user_data() is NULL after skb_gro_remcsum_init().
References
- https://git.kernel.org/stable/c/08f40c0d23c67c3aa4224c3311e134999c721fb4
- https://git.kernel.org/stable/c/30a45c0bffdd62350261e2f2689fdba426a33578
- https://git.kernel.org/stable/c/4a8cde6f7281ea2c4c290f9ad9923b3631defceb
- https://git.kernel.org/stable/c/9c58c729d32e7cea5772cc44929c6cd61e5a31cd
- https://git.kernel.org/stable/c/ef44dac2a37f86eeae6b88ed10a6d60b35387dfd
- https://git.kernel.org/stable/c/f79c80f173fda9545b220c1f094b65fc06c252d0