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net/tls: Protect from calling tls_dev_del for TLS RX twice

[ Upstream commit 025cc2fb6a ]

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: e8f6979981 ("net/tls: Add generic NIC offload infrastructure")
Signed-off-by: Maxim Mikityanskiy <maximmi@mellanox.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Link: https://lore.kernel.org/r/20201125221810.69870-1-saeedm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
5.4-rM2-2.2.x-imx-squashed
Maxim Mikityanskiy 2020-11-25 14:18:10 -08:00 committed by Greg Kroah-Hartman
parent a6300aedf8
commit f2f25bc797
2 changed files with 10 additions and 1 deletions

View File

@ -221,6 +221,12 @@ 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 {

View File

@ -1163,6 +1163,8 @@ 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);
@ -1192,7 +1194,8 @@ 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);