Fix AF_PACKET ABI breakage in 4.2

Commit 7d82410950 ("virtio: add explicit big-endian support to memory
accessors") accidentally changed the virtio_net header used by
AF_PACKET with PACKET_VNET_HDR from host-endian to big-endian.

Since virtio_legacy_is_little_endian() is a very long identifier,
define a vio_le macro and use that throughout the code instead of the
hard-coded 'false' for little-endian.

This restores the ABI to match 4.1 and earlier kernels, and makes my
test program work again.

Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Woodhouse 2015-09-23 19:45:08 +01:00 committed by David S. Miller
parent 2d8bff1269
commit d3869efe7a

View File

@ -230,6 +230,8 @@ struct packet_skb_cb {
} sa;
};
#define vio_le() virtio_legacy_is_little_endian()
#define PACKET_SKB_CB(__skb) ((struct packet_skb_cb *)((__skb)->cb))
#define GET_PBDQC_FROM_RB(x) ((struct tpacket_kbdq_core *)(&(x)->prb_bdqc))
@ -2680,15 +2682,15 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
goto out_unlock;
if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) &&
(__virtio16_to_cpu(false, vnet_hdr.csum_start) +
__virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2 >
__virtio16_to_cpu(false, vnet_hdr.hdr_len)))
vnet_hdr.hdr_len = __cpu_to_virtio16(false,
__virtio16_to_cpu(false, vnet_hdr.csum_start) +
__virtio16_to_cpu(false, vnet_hdr.csum_offset) + 2);
(__virtio16_to_cpu(vio_le(), vnet_hdr.csum_start) +
__virtio16_to_cpu(vio_le(), vnet_hdr.csum_offset) + 2 >
__virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len)))
vnet_hdr.hdr_len = __cpu_to_virtio16(vio_le(),
__virtio16_to_cpu(vio_le(), vnet_hdr.csum_start) +
__virtio16_to_cpu(vio_le(), vnet_hdr.csum_offset) + 2);
err = -EINVAL;
if (__virtio16_to_cpu(false, vnet_hdr.hdr_len) > len)
if (__virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len) > len)
goto out_unlock;
if (vnet_hdr.gso_type != VIRTIO_NET_HDR_GSO_NONE) {
@ -2731,7 +2733,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
hlen = LL_RESERVED_SPACE(dev);
tlen = dev->needed_tailroom;
skb = packet_alloc_skb(sk, hlen + tlen, hlen, len,
__virtio16_to_cpu(false, vnet_hdr.hdr_len),
__virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len),
msg->msg_flags & MSG_DONTWAIT, &err);
if (skb == NULL)
goto out_unlock;
@ -2778,8 +2780,8 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
if (po->has_vnet_hdr) {
if (vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) {
u16 s = __virtio16_to_cpu(false, vnet_hdr.csum_start);
u16 o = __virtio16_to_cpu(false, vnet_hdr.csum_offset);
u16 s = __virtio16_to_cpu(vio_le(), vnet_hdr.csum_start);
u16 o = __virtio16_to_cpu(vio_le(), vnet_hdr.csum_offset);
if (!skb_partial_csum_set(skb, s, o)) {
err = -EINVAL;
goto out_free;
@ -2787,7 +2789,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len)
}
skb_shinfo(skb)->gso_size =
__virtio16_to_cpu(false, vnet_hdr.gso_size);
__virtio16_to_cpu(vio_le(), vnet_hdr.gso_size);
skb_shinfo(skb)->gso_type = gso_type;
/* Header must be checked, and gso_segs computed. */
@ -3161,9 +3163,9 @@ static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
/* This is a hint as to how much should be linear. */
vnet_hdr.hdr_len =
__cpu_to_virtio16(false, skb_headlen(skb));
__cpu_to_virtio16(vio_le(), skb_headlen(skb));
vnet_hdr.gso_size =
__cpu_to_virtio16(false, sinfo->gso_size);
__cpu_to_virtio16(vio_le(), sinfo->gso_size);
if (sinfo->gso_type & SKB_GSO_TCPV4)
vnet_hdr.gso_type = VIRTIO_NET_HDR_GSO_TCPV4;
else if (sinfo->gso_type & SKB_GSO_TCPV6)
@ -3181,9 +3183,9 @@ static int packet_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
if (skb->ip_summed == CHECKSUM_PARTIAL) {
vnet_hdr.flags = VIRTIO_NET_HDR_F_NEEDS_CSUM;
vnet_hdr.csum_start = __cpu_to_virtio16(false,
vnet_hdr.csum_start = __cpu_to_virtio16(vio_le(),
skb_checksum_start_offset(skb));
vnet_hdr.csum_offset = __cpu_to_virtio16(false,
vnet_hdr.csum_offset = __cpu_to_virtio16(vio_le(),
skb->csum_offset);
} else if (skb->ip_summed == CHECKSUM_UNNECESSARY) {
vnet_hdr.flags = VIRTIO_NET_HDR_F_DATA_VALID;