This reverts commit 1f250674085aeb4ffd15ac2519a68efc04faf7ac.
rte_net_get_ptype() now uses |= to set the L2 ptype inside the VLAN
parsing loop. Since pkt_type is already initialized with
RTE_PTYPE_L2_ETHER (0x1), or-ing it with RTE_PTYPE_L2_ETHER_VLAN (0x6)
results in RTE_PTYPE_L2_ETHER_QINQ (0x7). This causes single VLAN frames
to be misidentified as QinQ.
This was detected while testing DPDK 25.11.1 in grout. The net/tap
driver calls rte_net_get_ptype() in tap_verify_csum() to determine the
L2 header length. With the wrong ptype, l2_len is set to 22 (ether
+ QinQ = 14 + 8) instead of 18 (ether + VLAN = 14 + 4), shifting the IP
header pointer by 4 bytes. The checksum is then computed on garbage
data, causing valid packets to be dropped.
Bugzilla ID: 1941
Fixes: 1f250674085a ("net: fix packet type for stacked VLAN")
Cc: [email protected]
Signed-off-by: Robin Jarry <[email protected]>
---
lib/net/rte_net.c | 29 +++++++++++++++--------------
1 file changed, 15 insertions(+), 14 deletions(-)
diff --git a/lib/net/rte_net.c b/lib/net/rte_net.c
index 458b4814a9c9..c70b57fdc0f8 100644
--- a/lib/net/rte_net.c
+++ b/lib/net/rte_net.c
@@ -320,9 +320,6 @@ rte_net_skip_ip6_ext(uint16_t proto, const struct rte_mbuf
*m, uint32_t *off,
return -1;
}
-/* limit number of supported VLAN headers */
-#define RTE_NET_VLAN_MAX_DEPTH 8
-
/* parse mbuf data to get packet type */
RTE_EXPORT_SYMBOL(rte_net_get_ptype)
uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
@@ -332,7 +329,7 @@ uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
const struct rte_ether_hdr *eh;
struct rte_ether_hdr eh_copy;
uint32_t pkt_type = RTE_PTYPE_L2_ETHER;
- uint32_t off = 0, vlan_depth = 0;
+ uint32_t off = 0;
uint16_t proto;
int ret;
@@ -352,26 +349,30 @@ uint32_t rte_net_get_ptype(const struct rte_mbuf *m,
if (proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_IPV4))
goto l3; /* fast path if packet is IPv4 */
- while (proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_VLAN) ||
- proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_QINQ)) {
+ if (proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_VLAN)) {
const struct rte_vlan_hdr *vh;
struct rte_vlan_hdr vh_copy;
- if (++vlan_depth > RTE_NET_VLAN_MAX_DEPTH)
- return 0;
- pkt_type |=
- proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_VLAN) ?
- RTE_PTYPE_L2_ETHER_VLAN :
- RTE_PTYPE_L2_ETHER_QINQ;
+ pkt_type = RTE_PTYPE_L2_ETHER_VLAN;
vh = rte_pktmbuf_read(m, off, sizeof(*vh), &vh_copy);
if (unlikely(vh == NULL))
return pkt_type;
off += sizeof(*vh);
hdr_lens->l2_len += sizeof(*vh);
proto = vh->eth_proto;
- }
+ } else if (proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_QINQ)) {
+ const struct rte_vlan_hdr *vh;
+ struct rte_vlan_hdr vh_copy;
- if ((proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_MPLS)) ||
+ pkt_type = RTE_PTYPE_L2_ETHER_QINQ;
+ vh = rte_pktmbuf_read(m, off + sizeof(*vh), sizeof(*vh),
+ &vh_copy);
+ if (unlikely(vh == NULL))
+ return pkt_type;
+ off += 2 * sizeof(*vh);
+ hdr_lens->l2_len += 2 * sizeof(*vh);
+ proto = vh->eth_proto;
+ } else if ((proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_MPLS)) ||
(proto == rte_cpu_to_be_16(RTE_ETHER_TYPE_MPLSM))) {
unsigned int i;
const struct rte_mpls_hdr *mh;
--
2.54.0
