3.12-stable review patch. If anyone has any objections, please let me know.
------------------ From: Jason Wang <[email protected]> [ Upstream commit e6fd07c899cd719bb5517bc7f32ce03a62220351 ] Commit 6680ec68eff47d36f67b4351bc9836fd6cba9532 (tuntap: hardware vlan tx support) breaks the truncated packet signal by nev return a length greater than iov length in tun_put_user(). This patch fixes by always return the length of packet plus possible vlan header. Caller can detect the truncated packet by comparing the return value and the size of io length. Cc: Zhi Yong Wu <[email protected]> Cc: Michael S. Tsirkin <[email protected]> Signed-off-by: Vlad Yasevich <[email protected]> Signed-off-by: Jason Wang <[email protected]> Acked-by: Michael S. Tsirkin <[email protected]> Signed-off-by: David S. Miller <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/net/tun.c | 16 +++++++++------- 1 file changed, 9 insertions(+), 7 deletions(-) --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1184,7 +1184,7 @@ static ssize_t tun_put_user(struct tun_s { struct tun_pi pi = { 0, skb->protocol }; ssize_t total = 0; - int vlan_offset = 0; + int vlan_offset = 0, copied; if (!(tun->flags & TUN_NO_PI)) { if ((len -= sizeof(pi)) < 0) @@ -1248,6 +1248,8 @@ static ssize_t tun_put_user(struct tun_s total += tun->vnet_hdr_sz; } + copied = total; + total += skb->len; if (!vlan_tx_tag_present(skb)) { len = min_t(int, skb->len, len); } else { @@ -1262,24 +1264,24 @@ static ssize_t tun_put_user(struct tun_s vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); len = min_t(int, skb->len + VLAN_HLEN, len); + total += VLAN_HLEN; copy = min_t(int, vlan_offset, len); - ret = skb_copy_datagram_const_iovec(skb, 0, iv, total, copy); + ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy); len -= copy; - total += copy; + copied += copy; if (ret || !len) goto done; copy = min_t(int, sizeof(veth), len); - ret = memcpy_toiovecend(iv, (void *)&veth, total, copy); + ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy); len -= copy; - total += copy; + copied += copy; if (ret || !len) goto done; } - skb_copy_datagram_const_iovec(skb, vlan_offset, iv, total, len); - total += len; + skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len); done: tun->dev->stats.tx_packets++; -- 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/
