Revert "net/tls: avoid NULL-deref on resync during device removal"

This reverts commit 48bf54da97dfd3514e28d9fb387f41c27e613333.
Unfortunately the RX resync may get called from soft IRQ,
so we can't take the rwsem to protect from the device
disappearing.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c
index b95c408fd771452a4ae2f026eb3f6785cf8c89bf..49b3a2ff8ef30edcec6e3622eeaddf036f4d71b2 100644 (file)
--- a/net/tls/tls_device.c
+++ b/net/tls/tls_device.c
@@ -553,8 +553,8 @@ void tls_device_write_space(struct sock *sk, struct tls_context *ctx)
 void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn)
 {
        struct tls_context *tls_ctx = tls_get_ctx(sk);
+       struct net_device *netdev = tls_ctx->netdev;
        struct tls_offload_context_rx *rx_ctx;
-       struct net_device *netdev;
        u32 is_req_pending;
        s64 resync_req;
        u32 req_seq;
@@ -568,15 +568,10 @@ void handle_device_resync(struct sock *sk, u32 seq, u64 rcd_sn)
        is_req_pending = resync_req;
 
        if (unlikely(is_req_pending) && req_seq == seq &&
-           atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0)) {
-               seq += TLS_HEADER_SIZE - 1;
-               down_read(&device_offload_lock);
-               netdev = tls_ctx->netdev;
-               if (netdev)
-                       netdev->tlsdev_ops->tls_dev_resync_rx(netdev, sk, seq,
-                                                             rcd_sn);
-               up_read(&device_offload_lock);
-       }
+           atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0))
+               netdev->tlsdev_ops->tls_dev_resync_rx(netdev, sk,
+                                                     seq + TLS_HEADER_SIZE - 1,
+                                                     rcd_sn);
 }
 
 static int tls_device_reencrypt(struct sock *sk, struct sk_buff *skb)