[PATCH 4.14 33/71] net/tls: Fix inverted error codes to avoid endless loop

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: "r.her...@avm.de" <r.her...@avm.de>


[ Upstream commit 30be8f8dba1bd2aff73e8447d59228471233a3d4 ]

sendfile() calls can hang endless with using Kernel TLS if a socket error 
occurs.
Socket error codes must be inverted by Kernel TLS before returning because
they are stored with positive sign. If returned non-inverted they are
interpreted as number of bytes sent, causing endless looping of the
splice mechanic behind sendfile().

Signed-off-by: Robert Hering <r.her...@avm.de>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 include/net/tls.h |    2 +-
 net/tls/tls_sw.c  |    4 ++--
 2 files changed, 3 insertions(+), 3 deletions(-)

--- a/include/net/tls.h
+++ b/include/net/tls.h
@@ -168,7 +168,7 @@ static inline bool tls_is_pending_open_r
 
 static inline void tls_err_abort(struct sock *sk)
 {
-       sk->sk_err = -EBADMSG;
+       sk->sk_err = EBADMSG;
        sk->sk_error_report(sk);
 }
 
--- a/net/tls/tls_sw.c
+++ b/net/tls/tls_sw.c
@@ -407,7 +407,7 @@ int tls_sw_sendmsg(struct sock *sk, stru
 
        while (msg_data_left(msg)) {
                if (sk->sk_err) {
-                       ret = sk->sk_err;
+                       ret = -sk->sk_err;
                        goto send_end;
                }
 
@@ -560,7 +560,7 @@ int tls_sw_sendpage(struct sock *sk, str
                size_t copy, required_size;
 
                if (sk->sk_err) {
-                       ret = sk->sk_err;
+                       ret = -sk->sk_err;
                        goto sendpage_end;
                }