From 2db05cd199999d9a3670e5287d067bdab0431f1a Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=C3=81lvaro=20Fern=C3=A1ndez=20Rojas?= Date: Sun, 23 Apr 2017 13:48:05 +0200 Subject: kernel: use skb_cow_head() to deal with cloned skbs MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit We need to ensure there is enough headroom to push extra header, but we also need to check if we are allowed to change headers. skb_cow_head() is the proper helper to deal with this. Fixes Ethernet<->WiFi bridge for Raspberry Pi and probably other devices. Signed-off-by: Álvaro Fernández Rojas --- ...use-skb_cow_head-to-deal-with-cloned-skbs.patch | 36 ++++++++++++++++++++++ 1 file changed, 36 insertions(+) create mode 100644 target/linux/generic/patches-4.9/023-2-smsc75xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch (limited to 'target/linux/generic/patches-4.9/023-2-smsc75xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch') diff --git a/target/linux/generic/patches-4.9/023-2-smsc75xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch b/target/linux/generic/patches-4.9/023-2-smsc75xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch new file mode 100644 index 0000000000..99d98e101c --- /dev/null +++ b/target/linux/generic/patches-4.9/023-2-smsc75xx-use-skb_cow_head-to-deal-with-cloned-skbs.patch @@ -0,0 +1,36 @@ +From b7c6d2675899cfff0180412c63fc9cbd5bacdb4d Mon Sep 17 00:00:00 2001 +From: Eric Dumazet +Date: Wed, 19 Apr 2017 09:59:21 -0700 +Subject: [PATCH] smsc75xx: use skb_cow_head() to deal with cloned skbs + +We need to ensure there is enough headroom to push extra header, +but we also need to check if we are allowed to change headers. + +skb_cow_head() is the proper helper to deal with this. + +Fixes: d0cad871703b ("smsc75xx: SMSC LAN75xx USB gigabit ethernet adapter driver") +Signed-off-by: Eric Dumazet +Cc: James Hughes +Signed-off-by: David S. Miller +--- + drivers/net/usb/smsc75xx.c | 8 ++------ + 1 file changed, 2 insertions(+), 6 deletions(-) + +--- a/drivers/net/usb/smsc75xx.c ++++ b/drivers/net/usb/smsc75xx.c +@@ -2205,13 +2205,9 @@ static struct sk_buff *smsc75xx_tx_fixup + { + u32 tx_cmd_a, tx_cmd_b; + +- if (skb_headroom(skb) < SMSC75XX_TX_OVERHEAD) { +- struct sk_buff *skb2 = +- skb_copy_expand(skb, SMSC75XX_TX_OVERHEAD, 0, flags); ++ if (skb_cow_head(skb, SMSC75XX_TX_OVERHEAD)) { + dev_kfree_skb_any(skb); +- skb = skb2; +- if (!skb) +- return NULL; ++ return NULL; + } + + tx_cmd_a = (u32)(skb->len & TX_CMD_A_LEN) | TX_CMD_A_FCS; -- cgit v1.2.3