diff --git a/hw/e1000.c b/hw/e1000.c index cb7e7e83661767a1a34bbb1f65601abbda7ffd61..5537ad2fc406446881caf1fa267b542d3e59bbfd 100644 --- a/hw/e1000.c +++ b/hw/e1000.c @@ -59,6 +59,9 @@ static int debugflags = DBGBIT(TXERR) | DBGBIT(GENERAL); #define PNPMMIO_SIZE 0x20000 #define MIN_BUF_SIZE 60 /* Min. octets in an ethernet frame sans FCS */ +/* this is the size past which hardware will drop packets when setting LPE=0 */ +#define MAXIMUM_ETHERNET_VLAN_SIZE 1522 + /* * HW models: * E1000_DEV_ID_82540EM works with Windows and Linux @@ -805,6 +808,13 @@ e1000_receive(NetClientState *nc, const uint8_t *buf, size_t size) size = sizeof(min_buf); } + /* Discard oversized packets if !LPE and !SBP. */ + if (size > MAXIMUM_ETHERNET_VLAN_SIZE + && !(s->mac_reg[RCTL] & E1000_RCTL_LPE) + && !(s->mac_reg[RCTL] & E1000_RCTL_SBP)) { + return size; + } + if (!receive_filter(s, buf, size)) return size;