From: Sukadev Bhattiprolu sukadev@linux.ibm.com
[ Upstream commit 76cdc5c5d99ce4856ad0ac38facc33b52fa64f77 ]
If after ibmvnic sends a LOGIN it gets a FAILOVER, it is possible that the worker thread will start reset process and free the login response buffer before it gets a (now stale) LOGIN_RSP. The ibmvnic tasklet will then try to access the login response buffer and crash.
Have ibmvnic track pending logins and discard any stale login responses.
Fixes: 032c5e82847a ("Driver for IBM System i/p VNIC protocol") Signed-off-by: Sukadev Bhattiprolu sukadev@linux.ibm.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/ethernet/ibm/ibmvnic.c | 17 +++++++++++++++++ drivers/net/ethernet/ibm/ibmvnic.h | 1 + 2 files changed, 18 insertions(+)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c index 006670f318bf1..9aa63b8b44368 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.c +++ b/drivers/net/ethernet/ibm/ibmvnic.c @@ -3843,6 +3843,8 @@ static int send_login(struct ibmvnic_adapter *adapter) crq.login.cmd = LOGIN; crq.login.ioba = cpu_to_be32(buffer_token); crq.login.len = cpu_to_be32(buffer_size); + + adapter->login_pending = true; ibmvnic_send_crq(adapter, &crq);
return 0; @@ -4374,6 +4376,15 @@ static int handle_login_rsp(union ibmvnic_crq *login_rsp_crq, struct ibmvnic_login_buffer *login = adapter->login_buf; int i;
+ /* CHECK: Test/set of login_pending does not need to be atomic + * because only ibmvnic_tasklet tests/clears this. + */ + if (!adapter->login_pending) { + netdev_warn(netdev, "Ignoring unexpected login response\n"); + return 0; + } + adapter->login_pending = false; + dma_unmap_single(dev, adapter->login_buf_token, adapter->login_buf_sz, DMA_TO_DEVICE); dma_unmap_single(dev, adapter->login_rsp_buf_token, @@ -4721,6 +4732,11 @@ static void ibmvnic_handle_crq(union ibmvnic_crq *crq, case IBMVNIC_CRQ_INIT: dev_info(dev, "Partner initialized\n"); adapter->from_passive_init = true; + /* Discard any stale login responses from prev reset. + * CHECK: should we clear even on INIT_COMPLETE? + */ + adapter->login_pending = false; + if (!completion_done(&adapter->init_done)) { complete(&adapter->init_done); adapter->init_done_rc = -EIO; @@ -5188,6 +5204,7 @@ static int ibmvnic_probe(struct vio_dev *dev, const struct vio_device_id *id) dev_set_drvdata(&dev->dev, netdev); adapter->vdev = dev; adapter->netdev = netdev; + adapter->login_pending = false;
ether_addr_copy(adapter->mac_addr, mac_addr_p); ether_addr_copy(netdev->dev_addr, adapter->mac_addr); diff --git a/drivers/net/ethernet/ibm/ibmvnic.h b/drivers/net/ethernet/ibm/ibmvnic.h index 31d604fc7bde7..77f43cbdb6dc4 100644 --- a/drivers/net/ethernet/ibm/ibmvnic.h +++ b/drivers/net/ethernet/ibm/ibmvnic.h @@ -1084,6 +1084,7 @@ struct ibmvnic_adapter { struct delayed_work ibmvnic_delayed_reset; unsigned long resetting; bool napi_enabled, from_passive_init; + bool login_pending;
bool failover_pending; bool force_reset_recovery;