From 743495144208cd1871ce0971ae6c57925141c855 Mon Sep 17 00:00:00 2001 From: Akihiko Odaki Date: Tue, 23 May 2023 11:43:07 +0900 Subject: [PATCH] e1000x: Take CRC into consideration for size check Section 13.7.15 Receive Length Error Count says: > Packets over 1522 bytes are oversized if LongPacketEnable is 0b > (RCTL.LPE). If LongPacketEnable (LPE) is 1b, then an incoming packet > is considered oversized if it exceeds 16384 bytes. > These lengths are based on bytes in the received packet from > through , inclusively. As QEMU processes packets without CRC, the number of bytes for CRC need to be subtracted. This change adds some size definitions to be used to derive the new size thresholds to eth.h. Signed-off-by: Akihiko Odaki Signed-off-by: Jason Wang --- hw/net/e1000x_common.c | 10 +++++----- include/net/eth.h | 2 ++ 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/hw/net/e1000x_common.c b/hw/net/e1000x_common.c index 6cc23138a8..212873fd77 100644 --- a/hw/net/e1000x_common.c +++ b/hw/net/e1000x_common.c @@ -140,16 +140,16 @@ bool e1000x_hw_rx_enabled(uint32_t *mac) bool e1000x_is_oversized(uint32_t *mac, size_t size) { + size_t header_size = sizeof(struct eth_header) + sizeof(struct vlan_header); /* this is the size past which hardware will drop packets when setting LPE=0 */ - static const int maximum_ethernet_vlan_size = 1522; + size_t maximum_short_size = header_size + ETH_MTU; /* this is the size past which hardware will drop packets when setting LPE=1 */ - static const int maximum_ethernet_lpe_size = 16 * KiB; + size_t maximum_large_size = 16 * KiB - ETH_FCS_LEN; - if ((size > maximum_ethernet_lpe_size || - (size > maximum_ethernet_vlan_size - && !(mac[RCTL] & E1000_RCTL_LPE))) + if ((size > maximum_large_size || + (size > maximum_short_size && !(mac[RCTL] & E1000_RCTL_LPE))) && !(mac[RCTL] & E1000_RCTL_SBP)) { e1000x_inc_reg_if_not_full(mac, ROC); trace_e1000x_rx_oversized(size); diff --git a/include/net/eth.h b/include/net/eth.h index e8af5742be..05f56931e7 100644 --- a/include/net/eth.h +++ b/include/net/eth.h @@ -32,6 +32,8 @@ #define ETH_ALEN 6 #define ETH_HLEN 14 #define ETH_ZLEN 60 /* Min. octets in frame without FCS */ +#define ETH_FCS_LEN 4 +#define ETH_MTU 1500 struct eth_header { uint8_t h_dest[ETH_ALEN]; /* destination eth addr */