From: Maxim Mikityanskiy <maximmi@xxxxxxxxxxxx>
[ Upstream commit 025cc2fb6a4e84e9a0552c0017dcd1c24b7ac7da ]
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 <maximmi@xxxxxxxxxxxx>
Signed-off-by: Saeed Mahameed <saeedm@xxxxxxxxxx>
Link: https://lore.kernel.org/r/20201125221810.69870-1-saeedm@xxxxxxxxxx
Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
include/net/tls.h | 6 ++++++
net/tls/tls_device.c | 5 ++++-
2 files changed, 10 insertions(+), 1 deletion(-)
--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -163,6 +163,12 @@ enum {
enum tls_context_flags {
TLS_RX_SYNC_RUNNING = 0,
+ /* 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 {
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -955,6 +955,8 @@ void tls_device_offload_cleanup_rx(struc
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);
@@ -984,7 +986,8 @@ static int tls_device_down(struct net_de
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);
