[PATCH 4.9 308/310] strparser: Fix sign of err codes

[Greg Kroah-Hartman]

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

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

From: Dave Watson <davejwatson@xxxxxx>


[ Upstream commit cd00edc179863848abab5cc5683de5b7b5f70954 ]

strp_parser_err is called with a negative code everywhere, which then
calls abort_parser with a negative code.  strp_msg_timeout calls
abort_parser directly with a positive code.  Negate ETIMEDOUT
to match signed-ness of other calls.

The default abort_parser callback, strp_abort_strp, sets
sk->sk_err to err.  Also negate the error here so sk_err always
holds a positive value, as the rest of the net code expects.  Currently
a negative sk_err can result in endless loops, or user code that
thinks it actually sent/received err bytes.

Found while testing net/tls_sw recv path.

Fixes: 43a0c6751a322847 ("strparser: Stream parser for messages")
Signed-off-by: Dave Watson <davejwatson@xxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/strparser/strparser.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/net/strparser/strparser.c
+++ b/net/strparser/strparser.c
@@ -59,7 +59,7 @@ static void strp_abort_rx_strp(struct st
 	strp->rx_stopped = 1;
 
 	/* Report an error on the lower socket */
-	csk->sk_err = err;
+	csk->sk_err = -err;
 	csk->sk_error_report(csk);
 }
 
@@ -422,7 +422,7 @@ static void strp_rx_msg_timeout(unsigned
 	/* Message assembly timed out */
 	STRP_STATS_INCR(strp->stats.rx_msg_timeouts);
 	lock_sock(strp->sk);
-	strp->cb.abort_parser(strp, ETIMEDOUT);
+	strp->cb.abort_parser(strp, -ETIMEDOUT);
 	release_sock(strp->sk);
 }