diff options
Diffstat (limited to 'net/core/selftests.c')
| -rw-r--r-- | net/core/selftests.c | 72 |
1 files changed, 68 insertions, 4 deletions
diff --git a/net/core/selftests.c b/net/core/selftests.c index 35f807ea9952..3d79133a91a6 100644 --- a/net/core/selftests.c +++ b/net/core/selftests.c @@ -27,6 +27,7 @@ struct net_packet_attrs { int max_size; u8 id; u16 queue_mapping; + bool bad_csum; }; struct net_test_priv { @@ -160,10 +161,25 @@ static struct sk_buff *net_test_get_skb(struct net_device *ndev, skb->csum = 0; skb->ip_summed = CHECKSUM_PARTIAL; if (attr->tcp) { - thdr->check = ~tcp_v4_check(skb->len, ihdr->saddr, - ihdr->daddr, 0); + int l4len = skb->len - skb_transport_offset(skb); + + thdr->check = ~tcp_v4_check(l4len, ihdr->saddr, ihdr->daddr, 0); skb->csum_start = skb_transport_header(skb) - skb->head; skb->csum_offset = offsetof(struct tcphdr, check); + + if (attr->bad_csum) { + /* Force mangled checksum */ + if (skb_checksum_help(skb)) { + kfree_skb(skb); + return NULL; + } + + if (thdr->check != CSUM_MANGLED_0) + thdr->check = CSUM_MANGLED_0; + else + thdr->check = csum16_sub(thdr->check, + cpu_to_be16(1)); + } } else { udp4_hwcsum(skb, ihdr->saddr, ihdr->daddr); } @@ -238,7 +254,11 @@ static int net_test_loopback_validate(struct sk_buff *skb, if (tpriv->packet->id != shdr->id) goto out; - tpriv->ok = true; + if (tpriv->packet->bad_csum && skb->ip_summed == CHECKSUM_UNNECESSARY) + tpriv->ok = -EIO; + else + tpriv->ok = true; + complete(&tpriv->comp); out: kfree_skb(skb); @@ -284,7 +304,12 @@ static int __net_test_loopback(struct net_device *ndev, attr->timeout = NET_LB_TIMEOUT; wait_for_completion_timeout(&tpriv->comp, attr->timeout); - ret = tpriv->ok ? 0 : -ETIMEDOUT; + if (tpriv->ok < 0) + ret = tpriv->ok; + else if (!tpriv->ok) + ret = -ETIMEDOUT; + else + ret = 0; cleanup: dev_remove_pack(&tpriv->pt); @@ -344,6 +369,42 @@ static int net_test_phy_loopback_tcp(struct net_device *ndev) return __net_test_loopback(ndev, &attr); } +/** + * net_test_phy_loopback_tcp_bad_csum - PHY loopback test with a deliberately + * corrupted TCP checksum + * @ndev: the network device to test + * + * Builds the same minimal Ethernet/IPv4/TCP frame as + * net_test_phy_loopback_tcp(), then flips the least-significant bit of the TCP + * checksum so the resulting value is provably invalid (neither 0 nor 0xFFFF). + * The frame is transmitted through the device’s internal PHY loopback path: + * + * test code -> MAC driver -> MAC HW -> xMII -> PHY -> + * internal PHY loopback -> xMII -> MAC HW -> MAC driver -> test code + * + * Result interpretation + * --------------------- + * 0 The frame is delivered to the stack and the driver reports + * ip_summed as CHECKSUM_NONE or CHECKSUM_COMPLETE - both are + * valid ways to indicate “bad checksum, let the stack verify.” + * -ETIMEDOUT The MAC/PHY silently dropped the frame; hardware checksum + * verification filtered it out before the driver saw it. + * -EIO The driver returned the frame with ip_summed == + * CHECKSUM_UNNECESSARY, falsely claiming a valid checksum and + * indicating a serious RX-path defect. + * + * Return: 0 on success or a negative error code on failure. + */ +static int net_test_phy_loopback_tcp_bad_csum(struct net_device *ndev) +{ + struct net_packet_attrs attr = { }; + + attr.dst = ndev->dev_addr; + attr.tcp = true; + attr.bad_csum = true; + return __net_test_loopback(ndev, &attr); +} + static const struct net_test { char name[ETH_GSTRING_LEN]; int (*fn)(struct net_device *ndev); @@ -368,6 +429,9 @@ static const struct net_test { .name = "PHY internal loopback, TCP ", .fn = net_test_phy_loopback_tcp, }, { + .name = "PHY loopback, bad TCP csum ", + .fn = net_test_phy_loopback_tcp_bad_csum, + }, { /* This test should be done after all PHY loopback test */ .name = "PHY internal loopback, disable", .fn = net_test_phy_loopback_disable, |