From: Sukadev Bhattiprolu <sukadev@xxxxxxxxxxxxx>
[ 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@xxxxxxxxxxxxx>
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
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;
--
2.27.0
