From d3f319cceadcbeaf100faa93386fc5021743709a Mon Sep 17 00:00:00 2001 From: Michal Luczaj Date: Thu, 7 Nov 2024 21:46:13 +0100 Subject: [PATCH] vsock: Fix sk_error_queue memory leak BugLink: https://bugs.launchpad.net/bugs/2101042 [ Upstream commit fbf7085b3ad1c7cc0677834c90f985f1b4f77a33 ] Kernel queues MSG_ZEROCOPY completion notifications on the error queue. Where they remain, until explicitly recv()ed. To prevent memory leaks, clean up the queue when the socket is destroyed. unreferenced object 0xffff8881028beb00 (size 224): comm "vsock_test", pid 1218, jiffies 4294694897 hex dump (first 32 bytes): 90 b0 21 17 81 88 ff ff 90 b0 21 17 81 88 ff ff ..!.......!..... 00 00 00 00 00 00 00 00 00 b0 21 17 81 88 ff ff ..........!..... backtrace (crc 6c7031ca): [] kmem_cache_alloc_node_noprof+0x2f7/0x370 [] __alloc_skb+0x132/0x180 [] sock_omalloc+0x4b/0x80 [] msg_zerocopy_realloc+0x9e/0x240 [] virtio_transport_send_pkt_info+0x412/0x4c0 [] virtio_transport_stream_enqueue+0x43/0x50 [] vsock_connectible_sendmsg+0x373/0x450 [] ____sys_sendmsg+0x365/0x3a0 [] ___sys_sendmsg+0x84/0xd0 [] __sys_sendmsg+0x47/0x80 [] do_syscall_64+0x93/0x180 [] entry_SYSCALL_64_after_hwframe+0x76/0x7e Fixes: 581512a6dc93 ("vsock/virtio: MSG_ZEROCOPY flag support") Signed-off-by: Michal Luczaj Reviewed-by: Stefano Garzarella Acked-by: Arseniy Krasnov Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin Signed-off-by: Manuel Diewald Signed-off-by: Stefan Bader --- net/vmw_vsock/af_vsock.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 55c1ac44b65e..f8619b88c49b 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -845,6 +845,9 @@ static void vsock_sk_destruct(struct sock *sk) { struct vsock_sock *vsk = vsock_sk(sk); + /* Flush MSG_ZEROCOPY leftovers. */ + __skb_queue_purge(&sk->sk_error_queue); + vsock_deassign_transport(vsk); /* When clearing these addresses, there's no need to set the family and