Commit b0d9ffcd authored by Michael Contreras's avatar Michael Contreras Committed by Anthony Liguori
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e1000: Discard packets that are too long if !SBP and !LPE 



The e1000_receive function for the e1000 needs to discard packets longer than
1522 bytes if the SBP and LPE flags are disabled. The linux driver assumes
this behavior and allocates memory based on this assumption.

Signed-off-by: default avatarMichael Contreras <michael@inetric.com>
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent 01bbd8bf

hw/e1000.c

+10 −0
Original line number Diff line number Diff line
@@ -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;