github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-14 16:10:02 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

net: Use helpers to get/set UDP len tree-wide

Browse Source 
Since BIG TCP for UDP tunnels will start using len=0 in the UDP header
as an indicator of a GSO packet bigger than 65535 bytes, this commit
introduces the following getter and setters to use tree-wide, in order
to explicitly mark places where len=0 may be expected, and handle them
properly:

1. udp_set_len() sets uh->len to its real value if it's not bigger than
65535, and to 0 otherwise: to be used in GSO context with aggregated
packets.

2. udp_set_len_short() is to be used when the length is known to fit 16
bits. It WARNs when the caller tries to assign a bigger value if
CONFIG_DEBUG_NET=y.

3. udp_get_len_short() returns len in host byte order: to be used on the
RX side to deal with non-aggregated packets, or to access the raw value
of the len field.

4. udp_get_len() decodes uh->len set by udp_set_len(). It checks whether
the packet is GSO to guard from malformed packets.

At the moment udp_set_len() is not used, a following commit will start
using it after enabling len>65535 for GSO.

Raw uh->len (in network byte order) is still accessed in a few places
for checksum calculation purposes, and to decode len=0 in udpv6_rcv for
jumbograms. udp_rcv and udpv6_rcv will be addressed by the commit that
starts using udp_set_len() to set UDP len=0 for BIG TCP packets in UDP
tunnels.

Signed-off-by: Alice Mikityanska <alice@isovalent.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://patch.msgid.link/20260710134242.216538-2-alice.kernel@fastmail.im
Reviewed-by: Nikolay Aleksandrov <razor@blackwall.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
This commit is contained in:
Alice Mikityanska 2026-07-10 16:42:34 +03:00 committed by Paolo Abeni
parent ba520084dc
commit 5329647dad
49 changed files with 131 additions and 88 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
drivers/infiniband/core/lag.c
View File

@ -36,7 +36,7 @@ static struct sk_buff *rdma_build_skb(struct net_device *netdev,
uh->source =
htons(rdma_flow_label_to_udp_sport(ah_attr->grh.flow_label));
uh->dest = htons(ROCE_V2_UDP_DPORT);
uh->len = htons(sizeof(struct udphdr));
udp_set_len_short(uh, sizeof(struct udphdr));
if (is_ipv4) {
skb_push(skb, sizeof(struct iphdr));

4
drivers/infiniband/sw/rxe/rxe_net.c
View File

@ -242,7 +242,7 @@ static int rxe_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
pkt->port_num = 1;
pkt->hdr = (u8 *)(udph + 1);
pkt->mask = RXE_GRH_MASK;
pkt->paylen = be16_to_cpu(udph->len) - sizeof(*udph);
pkt->paylen = udp_get_len_short(udph) - sizeof(*udph);
/* remove udp header */
skb_pull(skb, sizeof(struct udphdr));
@ -305,7 +305,7 @@ static void prepare_udp_hdr(struct sk_buff *skb, __be16 src_port,
udph->dest = dst_port;
udph->source = src_port;
udph->len = htons(skb->len);
udp_set_len_short(udph, skb->len);
udph->check = 0;
}

6
drivers/net/amt.c
View File

@ -667,7 +667,7 @@ static void amt_send_discovery(struct amt_dev *amt)
udph = udp_hdr(skb);
udph->source = amt->gw_port;
udph->dest = amt->relay_port;
udph->len = htons(sizeof(*udph) + sizeof(*amtd));
udp_set_len_short(udph, sizeof(*udph) + sizeof(*amtd));
udph->check = 0;
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
@ -760,7 +760,7 @@ static void amt_send_request(struct amt_dev *amt, bool v6)
udph = udp_hdr(skb);
udph->source = amt->gw_port;
udph->dest = amt->relay_port;
udph->len = htons(sizeof(*amtrh) + sizeof(*udph));
udp_set_len_short(udph, sizeof(*amtrh) + sizeof(*udph));
udph->check = 0;
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);
@ -2611,7 +2611,7 @@ static void amt_send_advertisement(struct amt_dev *amt, __be32 nonce,
udph = udp_hdr(skb);
udph->source = amt->relay_port;
udph->dest = dport;
udph->len = htons(sizeof(*amta) + sizeof(*udph));
udp_set_len_short(udph, sizeof(*amta) + sizeof(*udph));
udph->check = 0;
offset = skb_transport_offset(skb);
skb->csum = skb_checksum(skb, offset, skb->len - offset, 0);

2
drivers/net/ethernet/intel/i40e/i40e_txrx.c
View File

@ -3129,7 +3129,7 @@ static int i40e_tso(struct i40e_tx_buffer *first, u8 *hdr_len,
SKB_GSO_UDP_TUNNEL_CSUM)) {
if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
l4.udp->len = 0;
udp_set_len_short(l4.udp, 0);
/* determine offset of outer transport header */
l4_offset = l4.hdr - skb->data;

2
drivers/net/ethernet/intel/iavf/iavf_txrx.c
View File

@ -1774,7 +1774,7 @@ static int iavf_tso(struct iavf_tx_buffer *first, u8 *hdr_len,
SKB_GSO_UDP_TUNNEL_CSUM)) {
if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
l4.udp->len = 0;
udp_set_len_short(l4.udp, 0);
/* determine offset of outer transport header */
l4_offset = l4.hdr - skb->data;

2
drivers/net/ethernet/intel/ice/ice_txrx.c
View File

@ -1893,7 +1893,7 @@ int ice_tso(struct ice_tx_buf *first, struct ice_tx_offload_params *off)
SKB_GSO_UDP_TUNNEL_CSUM)) {
if (!(skb_shinfo(skb)->gso_type & SKB_GSO_PARTIAL) &&
(skb_shinfo(skb)->gso_type & SKB_GSO_UDP_TUNNEL_CSUM)) {
l4.udp->len = 0;
udp_set_len_short(l4.udp, 0);
/* determine offset of outer transport header */
l4_start = (u8)(l4.hdr - skb->data);

2
drivers/net/ethernet/intel/idpf/idpf_txrx.c
View File

@ -2871,7 +2871,7 @@ int idpf_tso(struct sk_buff *skb, struct idpf_tx_offload_params *off)
(__force __wsum)htonl(paylen));
/* compute length of segmentation header */
off->tso_hdr_len = sizeof(struct udphdr) + l4_start;
l4.udp->len = htons(shinfo->gso_size + sizeof(struct udphdr));
udp_set_len_short(l4.udp, shinfo->gso_size + sizeof(struct udphdr));
break;
default:
return -EINVAL;

2
drivers/net/ethernet/marvell/octeontx2/nic/otx2_txrx.c
View File

@ -750,7 +750,7 @@ static void otx2_sqe_add_ext(struct otx2_nic *pfvf, struct otx2_snd_queue *sq,
ext->lso_format = pfvf->hw.lso_udpv6_idx;
}
udph->len = htons(sizeof(struct udphdr));
udp_set_len_short(udph, sizeof(struct udphdr));
}
} else if (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) {
ext->tstmp = 1;

4
drivers/net/ethernet/mellanox/mlx5/core/en_rx.c
View File

@ -1081,7 +1081,7 @@ static void mlx5e_shampo_update_ipv4_udp_hdr(struct mlx5e_rq *rq, struct iphdr *
struct udphdr *uh;
uh = (struct udphdr *)(skb->data + udp_off);
uh->len = htons(skb->len - udp_off);
udp_set_len_short(uh, skb->len - udp_off);
if (uh->check)
uh->check = ~udp_v4_check(skb->len - udp_off, ipv4->saddr,
@ -1100,7 +1100,7 @@ static void mlx5e_shampo_update_ipv6_udp_hdr(struct mlx5e_rq *rq, struct ipv6hdr
struct udphdr *uh;
uh = (struct udphdr *)(skb->data + udp_off);
uh->len = htons(skb->len - udp_off);
udp_set_len_short(uh, skb->len - udp_off);
if (uh->check)
uh->check = ~udp_v6_check(skb->len - udp_off, &ipv6->saddr,

2
drivers/net/ethernet/mellanox/mlx5/core/en_selftest.c
View File

@ -113,7 +113,7 @@ static struct sk_buff *mlx5e_test_get_udp_skb(struct mlx5e_priv *priv)
/* Fill UDP header */
udph->source = htons(9);
udph->dest = htons(9); /* Discard Protocol */
udph->len = htons(sizeof(struct mlx5ehdr) + sizeof(struct udphdr));
udp_set_len_short(udph, sizeof(struct mlx5ehdr) + sizeof(struct udphdr));
udph->check = 0;
/* Fill IP header */

4
drivers/net/ethernet/sfc/falcon/selftest.c
View File

@ -401,8 +401,8 @@ static void ef4_iterate_state(struct ef4_nic *efx)
/* Initialise udp header */
payload->udp.source = 0;
payload->udp.len = htons(sizeof(*payload) -
offsetof(struct ef4_loopback_payload, udp));
udp_set_len_short(&payload->udp, sizeof(*payload) -
offsetof(struct ef4_loopback_payload, udp));
payload->udp.check = 0; /* checksum ignored */
/* Fill out payload */

4
drivers/net/ethernet/sfc/selftest.c
View File

@ -398,8 +398,8 @@ static void efx_iterate_state(struct efx_nic *efx)
/* Initialise udp header */
payload->udp.source = 0;
payload->udp.len = htons(sizeof(*payload) -
offsetof(struct efx_loopback_payload, udp));
udp_set_len_short(&payload->udp, sizeof(*payload) -
offsetof(struct efx_loopback_payload, udp));
payload->udp.check = 0; /* checksum ignored */
/* Fill out payload */

4
drivers/net/ethernet/sfc/siena/selftest.c
View File

@ -399,8 +399,8 @@ static void efx_iterate_state(struct efx_nic *efx)
/* Initialise udp header */
payload->udp.source = 0;
payload->udp.len = htons(sizeof(*payload) -
offsetof(struct efx_loopback_payload, udp));
udp_set_len_short(&payload->udp, sizeof(*payload) -
offsetof(struct efx_loopback_payload, udp));
payload->udp.check = 0; /* checksum ignored */
/* Fill out payload */

2
drivers/net/ethernet/sfc/tc_encap_actions.c
View File

@ -311,7 +311,7 @@ static void efx_gen_tun_header_udp(struct efx_tc_encap_action *encap, u8 len)
encap->encap_hdr_len += sizeof(*udp);
udp->dest = key->tp_dst;
udp->len = cpu_to_be16(sizeof(*udp) + len);
udp_set_len_short(udp, sizeof(*udp) + len);
}
static void efx_gen_tun_header_vxlan(struct efx_tc_encap_action *encap)

4
drivers/net/ethernet/stmicro/stmmac/stmmac_selftests.c
View File

@ -154,9 +154,9 @@ static struct sk_buff *stmmac_test_get_udp_skb(struct stmmac_priv *priv,
} else {
uhdr->source = htons(attr->sport);
uhdr->dest = htons(attr->dport);
uhdr->len = htons(sizeof(*shdr) + sizeof(*uhdr) + attr->size);
udp_set_len_short(uhdr, sizeof(*shdr) + sizeof(*uhdr) + attr->size);
if (attr->max_size)
uhdr->len = htons(attr->max_size -
udp_set_len_short(uhdr, attr->max_size -
(sizeof(*ihdr) + sizeof(*ehdr)));
uhdr->check = 0;
}

2
drivers/net/geneve.c
View File

@ -631,7 +631,7 @@ static int geneve_post_decap_hint(const struct sock *sk, struct sk_buff *skb,
/* Adjust the nested UDP header len and checksum. */
uh = udp_hdr(skb);
uh->len = htons(skb->len - gro_hint->nested_tp_offset);
udp_set_len_short(uh, skb->len - gro_hint->nested_tp_offset);
if (uh->check) {
len = skb->len - gro_hint->nested_tp_offset;
skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;

2
drivers/net/netconsole.c
View File

@ -1876,7 +1876,7 @@ static void push_udp(struct netpoll *np, struct sk_buff *skb, int len)
udph = udp_hdr(skb);
udph->source = htons(np->local_port);
udph->dest = htons(np->remote_port);
udph->len = htons(udp_len);
udp_set_len_short(udph, udp_len);
netpoll_udp_checksum(np, skb, len);
}

2
drivers/net/netdevsim/dev.c
View File

@ -845,7 +845,7 @@ static struct sk_buff *nsim_dev_trap_skb_build(void)
udph = skb_put_zero(skb, sizeof(struct udphdr) + data_len);
get_random_bytes(&udph->source, sizeof(u16));
get_random_bytes(&udph->dest, sizeof(u16));
udph->len = htons(sizeof(struct udphdr) + data_len);
udp_set_len_short(udph, sizeof(struct udphdr) + data_len);
return skb;
}

2
drivers/net/netdevsim/psample.c
View File

@ -73,7 +73,7 @@ static struct sk_buff *nsim_dev_psample_skb_build(void)
udph = skb_put_zero(skb, sizeof(struct udphdr) + data_len);
get_random_bytes(&udph->source, sizeof(u16));
get_random_bytes(&udph->dest, sizeof(u16));
udph->len = htons(sizeof(struct udphdr) + data_len);
udp_set_len_short(udph, sizeof(struct udphdr) + data_len);
return skb;
}

8
drivers/net/netdevsim/psp.c
View File

@ -84,6 +84,7 @@ nsim_do_psp(struct sk_buff *skb, struct netdevsim *ns,
struct iphdr *iph;
struct udphdr *uh;
__wsum csum;
int udplen;
/* Do not decapsulate. Receive the skb with the udp and psp
* headers still there as if this is a normal udp packet.
@ -91,19 +92,20 @@ nsim_do_psp(struct sk_buff *skb, struct netdevsim *ns,
* provide a valid checksum here, so the skb isn't dropped.
*/
uh = udp_hdr(skb);
udplen = udp_get_len(skb, uh, skb_transport_offset(skb));
csum = skb_checksum(skb, skb_transport_offset(skb),
ntohs(uh->len), 0);
udplen, 0);
switch (skb->protocol) {
case htons(ETH_P_IP):
iph = ip_hdr(skb);
uh->check = udp_v4_check(ntohs(uh->len), iph->saddr,
uh->check = udp_v4_check(udplen, iph->saddr,
iph->daddr, csum);
break;
#if IS_ENABLED(CONFIG_IPV6)
case htons(ETH_P_IPV6):
ip6h = ipv6_hdr(skb);
uh->check = udp_v6_check(ntohs(uh->len), &ip6h->saddr,
uh->check = udp_v6_check(udplen, &ip6h->saddr,
&ip6h->daddr, csum);
break;
#endif

2
drivers/net/wireguard/receive.c
View File

@ -62,7 +62,7 @@ static int prepare_skb_header(struct sk_buff *skb, struct wg_device *wg)
* to have UDP fields.
*/
return -EINVAL;
data_len = ntohs(udp->len);
data_len = udp_get_len_short(udp);
if (unlikely(data_len < sizeof(struct udphdr) ||
data_len > skb->len - data_offset))
/* UDP packet is reporting too small of a size or lying about

27
include/linux/udp.h
View File

@ -23,6 +23,33 @@ static inline struct udphdr *udp_hdr(const struct sk_buff *skb)
return (struct udphdr *)skb_transport_header(skb);
}
static inline unsigned int udp_get_len(const struct sk_buff *skb,
const struct udphdr *uh,
unsigned int dataoff)
{
if (uh->len)
return ntohs(uh->len);
if (skb_is_gso(skb)) /* BIG TCP */
return skb->len - dataoff;
return 0;
}
static inline unsigned int udp_get_len_short(const struct udphdr *uh)
{
return ntohs(uh->len);
}
static inline void udp_set_len(struct udphdr *uh, unsigned int len)
{
uh->len = len < GRO_LEGACY_MAX_SIZE ? htons(len) : 0;
}
static inline void udp_set_len_short(struct udphdr *uh, unsigned int len)
{
DEBUG_NET_WARN_ON_ONCE(len >= GRO_LEGACY_MAX_SIZE);
uh->len = htons(len);
}
#define UDP_HTABLE_SIZE_MIN_PERNET 128
#define UDP_HTABLE_SIZE_MIN (IS_ENABLED(CONFIG_BASE_SMALL) ? 128 : 256)
#define UDP_HTABLE_SIZE_MAX 65536

2
include/trace/events/icmp.h
View File

@ -44,7 +44,7 @@ TRACE_EVENT(icmp_send,
} else {
__entry->sport = ntohs(uh->source);
__entry->dport = ntohs(uh->dest);
__entry->ulen = ntohs(uh->len);
__entry->ulen = udp_get_len_short(uh);
}
p32 = (__be32 *) __entry->saddr;

2
lib/tests/blackhole_dev_kunit.c
View File

@ -46,7 +46,7 @@ static void test_blackholedev(struct kunit *test)
uh = (struct udphdr *)skb_push(skb, sizeof(struct udphdr));
skb_set_transport_header(skb, 0);
uh->source = uh->dest = htons(UDP_PORT);
uh->len = htons(data_len);
udp_set_len_short(uh, data_len);
uh->check = 0;
/* (Network) IPv6 */
ip6h = (struct ipv6hdr *)skb_push(skb, sizeof(struct ipv6hdr));

10
net/6lowpan/nhc_udp.c
View File

@ -88,16 +88,16 @@ static int udp_uncompress(struct sk_buff *skb, size_t needed)
switch (lowpan_dev(skb->dev)->lltype) {
case LOWPAN_LLTYPE_IEEE802154:
if (lowpan_802154_cb(skb)->d_size)
uh.len = htons(lowpan_802154_cb(skb)->d_size -
sizeof(struct ipv6hdr));
udp_set_len_short(&uh, lowpan_802154_cb(skb)->d_size -
sizeof(struct ipv6hdr));
else
uh.len = htons(skb->len + sizeof(struct udphdr));
udp_set_len_short(&uh, skb->len + sizeof(struct udphdr));
break;
default:
uh.len = htons(skb->len + sizeof(struct udphdr));
udp_set_len_short(&uh, skb->len + sizeof(struct udphdr));
break;
}
pr_debug("uncompressed UDP length: src = %d", ntohs(uh.len));
pr_debug("uncompressed UDP length: src = %d", udp_get_len_short(&uh));
/* replace the compressed UDP head by the uncompressed UDP
* header

4
net/core/pktgen.c
View File

@ -3005,7 +3005,7 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev,
udph->source = htons(pkt_dev->cur_udp_src);
udph->dest = htons(pkt_dev->cur_udp_dst);
udph->len = htons(datalen + 8); /* DATA + udphdr */
udp_set_len_short(udph, datalen + 8); /* DATA + udphdr */
udph->check = 0;
iph->ihl = 5;
@ -3138,7 +3138,7 @@ static struct sk_buff *fill_packet_ipv6(struct net_device *odev,
udplen = datalen + sizeof(struct udphdr);
udph->source = htons(pkt_dev->cur_udp_src);
udph->dest = htons(pkt_dev->cur_udp_dst);
udph->len = htons(udplen);
udp_set_len_short(udph, udplen);
udph->check = 0;
*(__be32 *) iph = htonl(0x60000000); /* Version + flow */

4
net/core/selftests.c
View File

@ -72,9 +72,9 @@ struct sk_buff *net_test_get_skb(struct net_device *ndev, u8 id,
} else {
uhdr->source = htons(attr->sport);
uhdr->dest = htons(attr->dport);
uhdr->len = htons(sizeof(*shdr) + sizeof(*uhdr) + attr->size);
udp_set_len_short(uhdr, sizeof(*shdr) + sizeof(*uhdr) + attr->size);
if (attr->max_size)
uhdr->len = htons(attr->max_size -
udp_set_len_short(uhdr, attr->max_size -
(sizeof(*ihdr) + sizeof(*ehdr)));
uhdr->check = 0;
}

3
net/core/tso.c
View File

@ -39,7 +39,8 @@ void tso_build_hdr(const struct sk_buff *skb, char *hdr, struct tso_t *tso,
} else {
struct udphdr *uh = (struct udphdr *)hdr;
uh->len = htons(sizeof(*uh) + size);
/* size is after segmentation. */
udp_set_len_short(uh, sizeof(*uh) + size);
}
}
EXPORT_SYMBOL(tso_build_hdr);

2
net/ipv4/esp4.c
View File

@ -323,7 +323,7 @@ static struct ip_esp_hdr *esp_output_udp_encap(struct sk_buff *skb,
uh = (struct udphdr *)esp->esph;
uh->source = sport;
uh->dest = dport;
uh->len = htons(len);
udp_set_len_short(uh, len);
uh->check = 0;
/* For IPv4 ESP with UDP encapsulation, if xo is not null, the skb is in the crypto offload

2
net/ipv4/fou_core.c
View File

@ -1040,7 +1040,7 @@ static void fou_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e,
uh->dest = e->dport;
uh->source = sport;
uh->len = htons(skb->len);
udp_set_len_short(uh, skb->len);
udp_set_csum(!(e->flags & TUNNEL_ENCAP_FLAG_CSUM), skb,
fl4->saddr, fl4->daddr, skb->len);

6
net/ipv4/ipconfig.c
View File

@ -847,7 +847,7 @@ static void __init ic_bootp_send_if(struct ic_device *d, unsigned long jiffies_d
/* Construct UDP header */
b->udph.source = htons(68);
b->udph.dest = htons(67);
b->udph.len = htons(sizeof(struct bootp_pkt) - sizeof(struct iphdr));
udp_set_len_short(&b->udph, sizeof(struct bootp_pkt) - sizeof(struct iphdr));
/* UDP checksum not calculated -- explicitly allowed in BOOTP RFC */
/* Construct DHCP/BOOTP header */
@ -1025,10 +1025,10 @@ static int __init ic_bootp_recv(struct sk_buff *skb, struct net_device *dev, str
if (b->udph.source != htons(67) || b->udph.dest != htons(68))
goto drop;
if (ntohs(h->tot_len) < ntohs(b->udph.len) + sizeof(struct iphdr))
if (ntohs(h->tot_len) < udp_get_len_short(&b->udph) + sizeof(struct iphdr))
goto drop;
len = ntohs(b->udph.len) - sizeof(struct udphdr);
len = udp_get_len_short(&b->udph) - sizeof(struct udphdr);
ext_len = len - (sizeof(*b) -
sizeof(struct iphdr) -
sizeof(struct udphdr) -

4
net/ipv4/netfilter/nf_nat_snmp_basic_main.c
View File

@ -127,7 +127,7 @@ static int snmp_translate(struct nf_conn *ct, int dir, struct sk_buff *skb)
{
struct iphdr *iph = ip_hdr(skb);
struct udphdr *udph = (struct udphdr *)((__be32 *)iph + iph->ihl);
u16 datalen = ntohs(udph->len) - sizeof(struct udphdr);
u16 datalen = udp_get_len_short(udph) - sizeof(struct udphdr);
char *data = (unsigned char *)udph + sizeof(struct udphdr);
struct snmp_ctx ctx;
int ret;
@ -181,7 +181,7 @@ static int help(struct sk_buff *skb, unsigned int protoff,
* enough room for a UDP header. Just verify the UDP length field so we
* can mess around with the payload.
*/
if (ntohs(udph->len) != skb->len - (iph->ihl << 2)) {
if (udp_get_len_short(udph) != skb->len - (iph->ihl << 2)) {
nf_ct_helper_log(skb, ct, "dropping malformed packet\n");
return NF_DROP;
}

2
net/ipv4/route.c
View File

@ -3187,7 +3187,7 @@ static struct sk_buff *inet_rtm_getroute_build_skb(__be32 src, __be32 dst,
udph = skb_put_zero(skb, sizeof(struct udphdr));
udph->source = sport;
udph->dest = dport;
udph->len = htons(sizeof(struct udphdr));
udp_set_len_short(udph, sizeof(struct udphdr));
udph->check = 0;
break;
}

3
net/ipv4/udp.c
View File

@ -1108,7 +1108,8 @@ static int udp_send_skb(struct sk_buff *skb, struct flowi4 *fl4,
uh = udp_hdr(skb);
uh->source = inet_sk(sk)->inet_sport;
uh->dest = fl4->fl4_dport;
uh->len = htons(len);
/* Datagram length checked in udp_sendmsg. */
udp_set_len_short(uh, len);
uh->check = 0;
if (cork->gso_size) {

37
net/ipv4/udp_offload.c
View File

@ -279,11 +279,11 @@ static struct sk_buff *__skb_udp_tunnel_segment(struct sk_buff *skb,
* segment instead of the entire frame.
*/
if (gso_partial && skb_is_gso(skb)) {
uh->len = htons(skb_shinfo(skb)->gso_size +
SKB_GSO_CB(skb)->data_offset +
skb->head - (unsigned char *)uh);
udp_set_len_short(uh, skb_shinfo(skb)->gso_size +
SKB_GSO_CB(skb)->data_offset +
skb->head - (unsigned char *)uh);
} else {
uh->len = htons(len);
udp_set_len_short(uh, len);
}
if (!need_csum)
@ -468,7 +468,7 @@ static struct sk_buff *__udp_gso_segment_list(struct sk_buff *skb,
if (IS_ERR(skb))
return skb;
udp_hdr(skb)->len = htons(sizeof(struct udphdr) + mss);
udp_set_len_short(udp_hdr(skb), sizeof(struct udphdr) + mss);
if (is_ipv6)
return __udpv6_gso_segment_list_csum(skb);
@ -486,8 +486,8 @@ struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
unsigned int mss;
bool copy_dtor;
__sum16 check;
__be16 newlen;
int ret = 0;
u16 newlen;
mss = skb_shinfo(gso_skb)->gso_size;
if (gso_skb->len <= sizeof(*uh) + mss)
@ -564,8 +564,8 @@ struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
(skb_shinfo(gso_skb)->tx_flags & SKBTX_ANY_TSTAMP);
/* compute checksum adjustment based on old length versus new */
newlen = htons(sizeof(*uh) + mss);
check = csum16_add(csum16_sub(uh->check, uh->len), newlen);
newlen = sizeof(*uh) + mss;
check = csum16_add(csum16_sub(uh->check, uh->len), htons(newlen));
for (;;) {
if (copy_dtor) {
@ -577,7 +577,7 @@ struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
if (!seg->next)
break;
uh->len = newlen;
udp_set_len_short(uh, newlen);
uh->check = check;
if (seg->ip_summed == CHECKSUM_PARTIAL)
@ -594,11 +594,10 @@ struct sk_buff *__udp_gso_segment(struct sk_buff *gso_skb,
* segment may not be full MSS, account for that in the checksum
*/
if (!skb_is_gso(seg))
newlen = htons(skb_tail_pointer(seg) -
skb_transport_header(seg) + seg->data_len);
check = csum16_add(csum16_sub(uh->check, uh->len), newlen);
newlen = skb_tail_pointer(seg) - skb_transport_header(seg) + seg->data_len;
check = csum16_add(csum16_sub(uh->check, uh->len), htons(newlen));
uh->len = newlen;
udp_set_len_short(uh, newlen);
uh->check = check;
if (seg->ip_summed == CHECKSUM_PARTIAL)
@ -709,7 +708,7 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head,
}
/* Do not deal with padded or malicious packets, sorry ! */
ulen = ntohs(uh->len);
ulen = udp_get_len_short(uh);
if (ulen <= sizeof(*uh) || ulen != skb_gro_len(skb)) {
NAPI_GRO_CB(skb)->flush = 1;
return NULL;
@ -742,7 +741,7 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head,
* On len mismatch merge the first packet shorter than gso_size,
* otherwise complete the GRO packet.
*/
if (ulen > ntohs(uh2->len) || flush) {
if (ulen > udp_get_len_short(uh2) || flush) {
pp = p;
} else {
if (NAPI_GRO_CB(skb)->is_flist) {
@ -765,7 +764,7 @@ static struct sk_buff *udp_gro_receive_segment(struct list_head *head,
}
}
if (ret || ulen != ntohs(uh2->len) ||
if (ret || ulen != udp_get_len_short(uh2) ||
NAPI_GRO_CB(p)->count >= UDP_GRO_CNT_MAX)
pp = p;
@ -915,12 +914,12 @@ static int udp_gro_complete_segment(struct sk_buff *skb)
int udp_gro_complete(struct sk_buff *skb, int nhoff,
udp_lookup_t lookup)
{
__be16 newlen = htons(skb->len - nhoff);
struct udphdr *uh = (struct udphdr *)(skb->data + nhoff);
unsigned int newlen = skb->len - nhoff;
struct sock *sk;
int err;
uh->len = newlen;
udp_set_len_short(uh, newlen);
sk = INDIRECT_CALL_INET(lookup, udp6_lib_lookup_skb,
udp4_lib_lookup_skb, skb, uh->source, uh->dest);
@ -957,7 +956,7 @@ INDIRECT_CALLABLE_SCOPE int udp4_gro_complete(struct sk_buff *skb, int nhoff)
/* do fraglist only if there is no outer UDP encap (or we already processed it) */
if (NAPI_GRO_CB(skb)->is_flist && !NAPI_GRO_CB(skb)->encap_mark) {
uh->len = htons(skb->len - nhoff);
udp_set_len_short(uh, skb->len - nhoff);
skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4);
skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count;

2
net/ipv4/udp_tunnel_core.c
View File

@ -178,7 +178,7 @@ void udp_tunnel_xmit_skb(struct rtable *rt, struct sock *sk, struct sk_buff *skb
uh->dest = dst_port;
uh->source = src_port;
uh->len = htons(skb->len);
udp_set_len_short(uh, skb->len);
memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));

5
net/ipv6/esp6.c
View File

@ -230,7 +230,8 @@ static void esp_output_encap_csum(struct sk_buff *skb)
if (*skb_mac_header(skb) == IPPROTO_UDP) {
struct udphdr *uh = udp_hdr(skb);
struct ipv6hdr *ip6h = ipv6_hdr(skb);
int len = ntohs(uh->len);
/* esp6_output_udp_encap limits len to U16_MAX. */
int len = udp_get_len_short(uh);
unsigned int offset = skb_transport_offset(skb);
__wsum csum = skb_checksum(skb, offset, skb->len - offset, 0);
@ -358,7 +359,7 @@ static struct ip_esp_hdr *esp6_output_udp_encap(struct sk_buff *skb,
uh = (struct udphdr *)esp->esph;
uh->source = sport;
uh->dest = dport;
uh->len = htons(len);
udp_set_len_short(uh, len);
uh->check = 0;
*skb_mac_header(skb) = IPPROTO_UDP;

2
net/ipv6/fou6.c
View File

@ -30,7 +30,7 @@ static void fou6_build_udp(struct sk_buff *skb, struct ip_tunnel_encap *e,
uh->dest = e->dport;
uh->source = sport;
uh->len = htons(skb->len);
udp_set_len_short(uh, skb->len);
udp6_set_csum(!(e->flags & TUNNEL_ENCAP_FLAG_CSUM6), skb,
&fl6->saddr, &fl6->daddr, skb->len);

2
net/ipv6/ip6_udp_tunnel.c
View File

@ -93,7 +93,7 @@ void udp_tunnel6_xmit_skb(struct dst_entry *dst, struct sock *sk,
uh->dest = dst_port;
uh->source = src_port;
uh->len = htons(skb->len);
udp_set_len_short(uh, skb->len);
skb_dst_set(skb, dst);

3
net/ipv6/udp.c
View File

@ -1369,7 +1369,8 @@ static int udp_v6_send_skb(struct sk_buff *skb, struct flowi6 *fl6,
uh = udp_hdr(skb);
uh->source = fl6->fl6_sport;
uh->dest = fl6->fl6_dport;
uh->len = htons(len);
/* Datagram length checked in udpv6_sendmsg. */
udp_set_len_short(uh, len);
uh->check = 0;
if (cork->gso_size) {

2
net/ipv6/udp_offload.c
View File

@ -171,7 +171,7 @@ int udp6_gro_complete(struct sk_buff *skb, int nhoff)
/* do fraglist only if there is no outer UDP encap (or we already processed it) */
if (NAPI_GRO_CB(skb)->is_flist && !NAPI_GRO_CB(skb)->encap_mark) {
uh->len = htons(skb->len - nhoff);
udp_set_len_short(uh, skb->len - nhoff);
skb_shinfo(skb)->gso_type |= (SKB_GSO_FRAGLIST|SKB_GSO_UDP_L4);
skb_shinfo(skb)->gso_segs = NAPI_GRO_CB(skb)->count;

2
net/l2tp/l2tp_core.c
View File

@ -1296,7 +1296,7 @@ static int l2tp_xmit_core(struct l2tp_session *session, struct sk_buff *skb, uns
ret = NET_XMIT_DROP;
goto out_unlock;
}
uh->len = htons(udp_len);
udp_set_len_short(uh, udp_len);
/* Calculate UDP checksum if configured to do so */
#if IS_ENABLED(CONFIG_IPV6)

2
net/netfilter/ipvs/ip_vs_xmit.c
View File

@ -1100,7 +1100,7 @@ ipvs_gue_encap(struct net *net, struct sk_buff *skb,
dport = cp->dest->tun_port;
udph->dest = dport;
udph->source = sport;
udph->len = htons(skb->len);
udp_set_len_short(udph, skb->len);
udph->check = 0;
*next_protocol = IPPROTO_UDP;

15
net/netfilter/nf_conntrack_proto_udp.c
View File

@ -41,11 +41,22 @@ static void udp_error_log(const struct sk_buff *skb,
nf_l4proto_log_invalid(skb, state, IPPROTO_UDP, "%s", msg);
}
static bool udp_validate_len(struct sk_buff *skb,
const struct udphdr *hdr,
unsigned int dataoff)
{
unsigned int udplen = udp_get_len_short(hdr);
unsigned int skblen = skb->len - dataoff;
if (udplen > skblen || udplen < sizeof(*hdr))
return false;
return true;
}
static bool udp_error(struct sk_buff *skb,
unsigned int dataoff,
const struct nf_hook_state *state)
{
unsigned int udplen = skb->len - dataoff;
const struct udphdr *hdr;
struct udphdr _hdr;
@ -57,7 +68,7 @@ static bool udp_error(struct sk_buff *skb,
}
/* Truncated/malformed packets */
if (ntohs(hdr->len) > udplen || ntohs(hdr->len) < sizeof(*hdr)) {
if (!udp_validate_len(skb, hdr, dataoff)) {
udp_error_log(skb, state, "truncated/malformed packet");
return true;
}

2
net/netfilter/nf_log_syslog.c
View File

@ -301,7 +301,7 @@ nf_log_dump_udp_header(struct nf_log_buf *m,
/* Max length: 20 "SPT=65535 DPT=65535 " */
nf_log_buf_add(m, "SPT=%u DPT=%u LEN=%u ",
ntohs(uh->source), ntohs(uh->dest), ntohs(uh->len));
ntohs(uh->source), ntohs(uh->dest), udp_get_len_short(uh));
out:
return 0;

2
net/netfilter/nf_nat_helper.c
View File

@ -161,7 +161,7 @@ nf_nat_mangle_udp_packet(struct sk_buff *skb,
/* update the length of the UDP packet */
datalen = skb->len - protoff;
udph->len = htons(datalen);
udp_set_len_short(udph, datalen);
/* fix udp checksum if udp checksum was previously calculated */
if (!udph->check && skb->ip_summed != CHECKSUM_PARTIAL)

2
net/psp/psp_main.c
View File

@ -231,7 +231,7 @@ static void psp_write_headers(struct net *net, struct sk_buff *skb, __be32 spi,
uh->source = udp_flow_src_port(net, skb, 0, 0, false);
}
uh->check = 0;
uh->len = htons(udp_len);
udp_set_len_short(uh, udp_len);
psph->nexthdr = IPPROTO_TCP;
psph->hdrlen = PSP_HDRLEN_NOOPT;

4
net/sched/act_csum.c
View File

@ -276,7 +276,7 @@ static int tcf_csum_ipv4_udp(struct sk_buff *skb, unsigned int ihl,
return 0;
iph = ip_hdr(skb);
ul = ntohs(udph->len);
ul = udp_get_len_short(udph);
if (udplite || udph->check) {
@ -334,7 +334,7 @@ static int tcf_csum_ipv6_udp(struct sk_buff *skb, unsigned int ihl,
return 0;
ip6h = ipv6_hdr(skb);
ul = ntohs(udph->len);
ul = udp_get_len_short(udph);
udph->check = 0;

2
net/xfrm/xfrm_nat_keepalive.c
View File

@ -133,7 +133,7 @@ static void nat_keepalive_send(struct nat_keepalive *ka)
uh = skb_push(skb, sizeof(*uh));
uh->source = ka->encap_sport;
uh->dest = ka->encap_dport;
uh->len = htons(skb->len);
udp_set_len_short(uh, skb->len);
uh->check = 0;
skb->mark = ka->smark;