openwrt/target/linux/generic/backport-4.9/023-1-smsc95xx-Use-skb_cow_head-to-deal-with-cloned-skbs.patch
Koen Vandeputte bcd7644007 kernel: bump 4.9 to 4.9.143
Refreshed all patches.

Altered patches:
- 950-0063-Improve-__copy_to_user-and-__copy_from_user-performa.patch
- 950-0149-Update-vfpmodule.c.patch
- 201-extra_optimization.patch

New symbol:
- CONFIG_HARDEN_BRANCH_PREDICTOR

Compile-tested on: ar71xx, ar7, arc770, at91, brcm2708, brcm63xx, ixp4xx, lantiq, layerscape, mpc85xx, orion, rb532, uml
Runtime-tested on: ar71xx

Signed-off-by: Koen Vandeputte <koen.vandeputte@ncentric.com>
2018-12-13 13:28:41 +01:00

41 lines
1.4 KiB
Diff

From e9156cd26a495a18706e796f02a81fee41ec14f4 Mon Sep 17 00:00:00 2001
From: James Hughes <james.hughes@raspberrypi.org>
Date: Wed, 19 Apr 2017 11:13:40 +0100
Subject: [PATCH] smsc95xx: Use skb_cow_head to deal with cloned skbs
The driver was failing to check that the SKB wasn't cloned
before adding checksum data.
Replace existing handling to extend/copy the header buffer
with skb_cow_head.
Signed-off-by: James Hughes <james.hughes@raspberrypi.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Woojung Huh <Woojung.Huh@microchip.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---
drivers/net/usb/smsc95xx.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
--- a/drivers/net/usb/smsc95xx.c
+++ b/drivers/net/usb/smsc95xx.c
@@ -2011,13 +2011,13 @@ static struct sk_buff *smsc95xx_tx_fixup
/* We do not advertise SG, so skbs should be already linearized */
BUG_ON(skb_shinfo(skb)->nr_frags);
- if (skb_headroom(skb) < overhead) {
- struct sk_buff *skb2 = skb_copy_expand(skb,
- overhead, 0, flags);
+ /* Make writable and expand header space by overhead if required */
+ if (skb_cow_head(skb, overhead)) {
+ /* Must deallocate here as returning NULL to indicate error
+ * means the skb won't be deallocated in the caller.
+ */
dev_kfree_skb_any(skb);
- skb = skb2;
- if (!skb)
- return NULL;
+ return NULL;
}
if (csum) {