From: Jarek Poplawski <jarkao2@gmail.com>
Date: Fri, 13 Feb 2009 00:51:43 +0000 (-0800)
Subject: net: Fix page seeking for skb_splice_bits().
X-Git-Url: http://git.cdn.openwrt.org/?a=commitdiff_plain;h=ce3dd39595d9d64f4ba6ee8dd24c6269a3b56b6a;p=openwrt%2Fstaging%2Fblogic.git

net: Fix page seeking for skb_splice_bits().

struct page walking should be done with proper accessor functions, not
directly.

With doubts from David S. Miller and Herbert Xu.

Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/net/core/skbuff.c b/net/core/skbuff.c
index 7657cec5973d..ab7d2e9f02fa 100644
--- a/net/core/skbuff.c
+++ b/net/core/skbuff.c
@@ -1412,8 +1412,13 @@ static inline int spd_fill_page(struct splice_pipe_desc *spd, struct page *page,
 static inline void __segment_seek(struct page **page, unsigned int *poff,
 				  unsigned int *plen, unsigned int off)
 {
+	unsigned long n;
+
 	*poff += off;
-	*page += *poff / PAGE_SIZE;
+	n = *poff / PAGE_SIZE;
+	if (n)
+		*page = nth_page(*page, n);
+
 	*poff = *poff % PAGE_SIZE;
 	*plen -= off;
 }