3.12-stable review patch. If anyone has any objections, please let me know.
------------------ From: "David S. Miller" <[email protected]> [ Upstream commit 2205369a314e12fcec4781cc73ac9c08fc2b47de ] When the vlan code detects that the real device can do TX VLAN offloads in hardware, it tries to arrange for the real device's header_ops to be invoked directly. But it does so illegally, by simply hooking the real device's header_ops up to the VLAN device. This doesn't work because we will end up invoking a set of header_ops routines which expect a device type which matches the real device, but will see a VLAN device instead. Fix this by providing a pass-thru set of header_ops which will arrange to pass the proper real device instead. To facilitate this add a dev_rebuild_header(). There are implementations which provide a ->cache and ->create but not a ->rebuild (f.e. PLIP). So we need a helper function just like dev_hard_header() to avoid crashes. Use this helper in the one existing place where the header_ops->rebuild was being invoked, the neighbour code. With lots of help from Florian Westphal. Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- include/linux/netdevice.h | 9 +++++++++ net/8021q/vlan_dev.c | 19 ++++++++++++++++++- net/core/neighbour.c | 2 +- 3 files changed, 28 insertions(+), 2 deletions(-) --- a/include/linux/netdevice.h +++ b/include/linux/netdevice.h @@ -1872,6 +1872,15 @@ static inline int dev_parse_header(const return dev->header_ops->parse(skb, haddr); } +static inline int dev_rebuild_header(struct sk_buff *skb) +{ + const struct net_device *dev = skb->dev; + + if (!dev->header_ops || !dev->header_ops->rebuild) + return 0; + return dev->header_ops->rebuild(skb); +} + typedef int gifconf_func_t(struct net_device * dev, char __user * bufptr, int len); extern int register_gifconf(unsigned int family, gifconf_func_t * gifconf); static inline int unregister_gifconf(unsigned int family) --- a/net/8021q/vlan_dev.c +++ b/net/8021q/vlan_dev.c @@ -549,6 +549,23 @@ static const struct header_ops vlan_head .parse = eth_header_parse, }; +static int vlan_passthru_hard_header(struct sk_buff *skb, struct net_device *dev, + unsigned short type, + const void *daddr, const void *saddr, + unsigned int len) +{ + struct vlan_dev_priv *vlan = vlan_dev_priv(dev); + struct net_device *real_dev = vlan->real_dev; + + return dev_hard_header(skb, real_dev, type, daddr, saddr, len); +} + +static const struct header_ops vlan_passthru_header_ops = { + .create = vlan_passthru_hard_header, + .rebuild = dev_rebuild_header, + .parse = eth_header_parse, +}; + static struct device_type vlan_type = { .name = "vlan", }; @@ -592,7 +609,7 @@ static int vlan_dev_init(struct net_devi dev->needed_headroom = real_dev->needed_headroom; if (real_dev->features & NETIF_F_HW_VLAN_CTAG_TX) { - dev->header_ops = real_dev->header_ops; + dev->header_ops = &vlan_passthru_header_ops; dev->hard_header_len = real_dev->hard_header_len; } else { dev->header_ops = &vlan_header_ops; --- a/net/core/neighbour.c +++ b/net/core/neighbour.c @@ -1274,7 +1274,7 @@ int neigh_compat_output(struct neighbour if (dev_hard_header(skb, dev, ntohs(skb->protocol), NULL, NULL, skb->len) < 0 && - dev->header_ops->rebuild(skb)) + dev_rebuild_header(skb)) return 0; return dev_queue_xmit(skb); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
