From: Maxim Mikityanskiy <maxi...@mellanox.com>
tls_device_offload_cleanup_rx doesn't clear tls_ctx->netdev after
calling tls_dev_del if TLX TX offload is also enabled. Clearing
tls_ctx->netdev gets postponed until tls_device_gc_task. It leaves a
time frame when tls_device_down may get called and call tls_dev_del for
RX one extra time, confusing the driver, which may lead to a crash.
This patch corrects this racy behavior by adding a flag to prevent
tls_device_down from calling tls_dev_del the second time.
Fixes: e8f69799810c ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Maxim Mikityanskiy <maxi...@mellanox.com>
Signed-off-by: Saeed Mahameed <sae...@nvidia.com>
---
v1->v2:
- Add comment explaining TLS_RX_DEV_RELEASED
- set the bit in else branch
include/net/tls.h | 6 ++++++
net/tls/tls_device.c | 4 +++-
2 files changed, 9 insertions(+), 1 deletion(-)
diff --git a/include/net/tls.h b/include/net/tls.h
index cf1473099453..2bdd802212fe 100644
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -199,6 +199,12 @@ enum tls_context_flags {
* to be atomic.
*/
TLS_TX_SYNC_SCHED = 1,
+ /* tls_dev_del was called for the RX side, device state was released,
+ * but tls_ctx->netdev might still be kept, because TX-side driver
+ * resources might not be released yet. Used to prevent the second
+ * tls_dev_del call in tls_device_down if it happens simultaneously.
+ */
+ TLS_RX_DEV_CLOSED = 2,
};
struct cipher_context {
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index 54d3e161d198..8c2125caeb8a 100644
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -1262,6 +1262,8 @@ void tls_device_offload_cleanup_rx(struct sock *sk)
if (tls_ctx->tx_conf != TLS_HW) {
dev_put(netdev);
tls_ctx->netdev = NULL;
+ } else {
+ set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags);
}
out:
up_read(&device_offload_lock);
@@ -1291,7 +1293,7 @@ static int tls_device_down(struct net_device *netdev)
if (ctx->tx_conf == TLS_HW)
netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
TLS_OFFLOAD_CTX_DIR_TX);
- if (ctx->rx_conf == TLS_HW)
+ if (ctx->rx_conf == TLS_HW && !test_bit(TLS_RX_DEV_CLOSED,
&ctx->flags))
netdev->tlsdev_ops->tls_dev_del(netdev, ctx,
TLS_OFFLOAD_CTX_DIR_RX);
WRITE_ONCE(ctx->netdev, NULL);
--
2.26.2
