net: tls: Fix deadlock in free_resources tx

If there are outstanding async tx requests (when crypto returns EINPROGRESS),
there is a potential deadlock: the tx work acquires the lock, while we
cancel_delayed_work_sync() while holding the lock.  Drop the lock while waiting
for the work to complete.

Fixes: a42055e8d2c30 ("Add support for async encryption of records...")
Signed-off-by: Dave Watson <davejwatson@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/tls/tls_sw.c b/net/tls/tls_sw.c
index 7e96356..bf5b54b 100644 (file)
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -1794,7 +1794,9 @@ void tls_sw_free_resources_tx(struct sock *sk)
        if (atomic_read(&ctx->encrypt_pending))
                crypto_wait_req(-EINPROGRESS, &ctx->async_wait);
 
+       release_sock(sk);
        cancel_delayed_work_sync(&ctx->tx_work.work);
+       lock_sock(sk);
 
        /* Tx whatever records we can transmit and abandon the rest */
        tls_tx_records(sk, -1);