From: Lepton Wu ytht.net@gmail.com
[ Upstream commit 8236b08cf50f85bbfaf48910a0b3ee68318b7c4b ]
The old code always starts from fixed port for VMADDR_PORT_ANY. Sometimes when VMM crashed, there is still orphaned vsock which is waiting for close timer, then it could cause connection time out for new started VM if they are trying to connect to same port with same guest cid since the new packets could hit that orphaned vsock. We could also fix this by doing more in vhost_vsock_reset_orphans, but any way, it should be better to start from a random local port instead of a fixed one.
Signed-off-by: Lepton Wu ytht.net@gmail.com Reviewed-by: Jorgen Hansen jhansen@vmware.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/vmw_vsock/af_vsock.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/net/vmw_vsock/af_vsock.c b/net/vmw_vsock/af_vsock.c index 7566395e526d2..18f377306884b 100644 --- a/net/vmw_vsock/af_vsock.c +++ b/net/vmw_vsock/af_vsock.c @@ -97,6 +97,7 @@ #include <linux/mutex.h> #include <linux/net.h> #include <linux/poll.h> +#include <linux/random.h> #include <linux/skbuff.h> #include <linux/smp.h> #include <linux/socket.h> @@ -501,9 +502,13 @@ out: static int __vsock_bind_stream(struct vsock_sock *vsk, struct sockaddr_vm *addr) { - static u32 port = LAST_RESERVED_PORT + 1; + static u32 port = 0; struct sockaddr_vm new_addr;
+ if (!port) + port = LAST_RESERVED_PORT + 1 + + prandom_u32_max(U32_MAX - LAST_RESERVED_PORT); + vsock_addr_init(&new_addr, addr->svm_cid, addr->svm_port);
if (addr->svm_port == VMADDR_PORT_ANY) {