4.9-stable patches

[thirdparty/kernel/stable-queue.git] / releases / 3.19.7 / net-add-skb_checksum_complete_unset.patch

From foo@baz Wed Apr 29 12:00:18 CEST 2015
From: Tom Herbert <tom@herbertland.com>
Date: Mon, 20 Apr 2015 14:10:04 -0700
Subject: net: add skb_checksum_complete_unset

From: Tom Herbert <tom@herbertland.com>

[ Upstream commit 4e18b9adf2f910ec4d30b811a74a5b626e6c6125 ]

This function changes ip_summed to CHECKSUM_NONE if CHECKSUM_COMPLETE
is set. This is called to discard checksum-complete when packet
is being modified and checksum is not pulled for headers in a layer.

Signed-off-by: Tom Herbert <tom@herbertland.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 include/linux/skbuff.h |   12 ++++++++++++
 1 file changed, 12 insertions(+)

--- a/include/linux/skbuff.h
+++ b/include/linux/skbuff.h
@@ -2998,6 +2998,18 @@ static inline bool __skb_checksum_valida
  */
 #define CHECKSUM_BREAK 76
 
+/* Unset checksum-complete
+ *
+ * Unset checksum complete can be done when packet is being modified
+ * (uncompressed for instance) and checksum-complete value is
+ * invalidated.
+ */
+static inline void skb_checksum_complete_unset(struct sk_buff *skb)
+{
+	if (skb->ip_summed == CHECKSUM_COMPLETE)
+		skb->ip_summed = CHECKSUM_NONE;
+}
+
 /* Validate (init) checksum based on checksum complete.
  *
  * Return values: