svc_tcp_sock_process_cmsg() decides whether an alert ends the session by reading the alert's level octet. RFC 8446 Section 6 retired that field. The severity is implicit in the description, and a receiver treats every alert listed in Section 6.2 as an error alert "regardless of the AlertLevel in the message". A peer that aborts with unexpected_message but leaves the legacy octet set to warning makes the server return -EAGAIN. svc_tcp_recvfrom() then leaves a dead TLS session attached to an open transport. NFSD keeps polling it. Decide from the alert description instead. close_notify and user_canceled are the closure alerts (RFC 8446 Section 6.1). Every other description ends the session, including one this kernel does not recognize. Fixes: 39067dda1d86 ("SUNRPC: Use new helpers to handle TLS Alerts") Signed-off-by: Chuck Lever --- net/sunrpc/svcsock.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-) diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c index 2e5107a1fb89..756db84e4aec 100644 --- a/net/sunrpc/svcsock.c +++ b/net/sunrpc/svcsock.c @@ -257,8 +257,18 @@ svc_tcp_sock_process_cmsg(struct socket *sock, struct msghdr *msg, break; case TLS_RECORD_TYPE_ALERT: tls_alert_recv(sock->sk, msg, &level, &description); - ret = (level == TLS_ALERT_LEVEL_FATAL) ? - -ENOTCONN : -EAGAIN; + /* RFC 8446 Section 6: every alert but a closure alert is + * an error alert, whatever the legacy AlertLevel octet + * says. + */ + switch (description) { + case TLS_ALERT_DESC_CLOSE_NOTIFY: + case TLS_ALERT_DESC_USER_CANCELED: + ret = -EAGAIN; + break; + default: + ret = -ENOTCONN; + } break; default: /* discard this record type */ -- 2.54.0