Wind River Support Network

Description

In the Linux kernel, the following vulnerability has been resolved:  net/tunnel: wait until all sk_user_data reader finish before releasing the sock  There is a race condition in vxlan that when deleting a vxlan device during receiving packets, there is a possibility that the sock is released after getting vxlan_sock vs from sk_user_data. Then in later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got NULL pointer dereference. e.g.     #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757    #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d    #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48    #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b    #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb    #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542    #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62       [exception RIP: vxlan_ecn_decapsulate+0x3b]       RIP: ffffffffc1014e7b  RSP: ffffa25ec6978cb0  RFLAGS: 00010246       RAX: 0000000000000008  RBX: ffff8aa000888000  RCX: 0000000000000000       RDX: 000000000000000e  RSI: ffff8a9fc7ab803e  RDI: ffff8a9fd1168700       RBP: ffff8a9fc7ab803e   R8: 0000000000700000   R9: 00000000000010ae       R10: ffff8a9fcb748980  R11: 0000000000000000  R12: ffff8a9fd1168700       R13: ffff8aa000888000  R14: 00000000002a0000  R15: 00000000000010ae       ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018    #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan]    #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507    #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45   #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807   #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951   #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde   #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b   #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139   #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a   #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3   #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca   #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3  Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh  Fix this by waiting for all sk_user_data reader to finish before releasing the sock.