kernel/linux.git/drivers/net/amt.c, branch v5.19

amt: do not use amt->nr_tunnels outside of lock

2022-07-19T10:37:02+00:00

amt->nr_tunnels is protected by amt->lock. But, amt_request_handler() has been using this variable without the amt->lock. So, it expands context of amt->lock in the amt_request_handler() to protect amt->nr_tunnels variable. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: drop unexpected multicast data

2022-07-19T10:37:02+00:00

AMT gateway interface should not receive unexpected multicast data. Multicast data message type should be received after sending an update message, which means all establishment between gateway and relay is finished. So, amt_multicast_data_handler() checks amt->status. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: drop unexpected query message

2022-07-19T10:37:02+00:00

AMT gateway interface should not receive unexpected query messages. In order to drop unexpected query messages, it checks nonce. And it also checks ready4 and ready6 variables to drop duplicated messages. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: drop unexpected advertisement message

2022-07-19T10:37:02+00:00

AMT gateway interface should not receive unexpected advertisement messages. In order to drop these packets, it should check nonce and amt->status. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: add missing regeneration nonce logic in request logic

2022-07-19T10:37:02+00:00

When AMT gateway starts sending a new request message, it should regenerate the nonce variable. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: use READ_ONCE() in amt module

2022-07-19T10:37:02+00:00

There are some data races in the amt module. amt->ready4, amt->ready6, and amt->status can be accessed concurrently without locks. So, it uses READ_ONCE() and WRITE_ONCE(). Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: remove unnecessary locks

2022-07-19T10:37:02+00:00

By the previous patch, amt gateway handlers are changed to worked by a single thread. So, most locks for gateway are not needed. So, it removes. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

amt: use workqueue for gateway side message handling

2022-07-19T10:37:02+00:00

There are some synchronization issues(amt->status, amt->req_cnt, etc) if the interface is in gateway mode because gateway message handlers are processed concurrently. This applies a work queue for processing these messages instead of expanding the locking context. So, the purposes of this patch are to fix exist race conditions and to make gateway to be able to validate a gateway status more correctly. When the AMT gateway interface is created, it tries to establish to relay. The establishment step looks stateless, but it should be managed well. In order to handle messages in the gateway, it saves the current status(i.e. AMT_STATUS_XXX). This patch makes gateway code to be worked with a single thread. Now, all messages except the multicast are triggered(received or delay expired), and these messages will be stored in the event queue(amt->events). Then, the single worker processes stored messages asynchronously one by one. The multicast data message type will be still processed immediately. Now, amt->lock is only needed to access the event queue(amt->events) if an interface is the gateway mode. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Paolo Abeni

igmp: Fix data-races around sysctl_igmp_qrv.

2022-07-18T11:21:54+00:00

While reading sysctl_igmp_qrv, it can be changed concurrently. Thus, we need to add READ_ONCE() to its readers. This test can be packed into a helper, so such changes will be in the follow-up series after net is merged into net-next. qrv ?: READ_ONCE(net->ipv4.sysctl_igmp_qrv); Fixes: a9fe8e29945d ("ipv4: implement igmp_qrv sysctl to tune igmp robustness variable") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller

amt: fix wrong type string definition

2022-06-06T21:27:35+00:00

amt message type definition starts from 1, not 0. But type_str[] starts from 0. So, it prints wrong type information. Fixes: cbc21dc1cfe9 ("amt: add data plane of amt interface") Signed-off-by: Taehee Yoo Signed-off-by: Jakub Kicinski