From b0b900070c7cb29bbefb732ec00397abe5de6d73 Mon Sep 17 00:00:00 2001
From: "Michael S. Tsirkin" <mst@redhat.com>
Date: Mon, 12 Jul 2010 20:24:59 +0300
Subject: [PATCH] e1000: fix access 4 bytes beyond buffer end
We do range check for size, and get size as buffer,
but copy size + 4 bytes (4 is for FCS).
Let's copy size bytes but put size + 4 in length.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
hw/e1000.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/hw/e1000.c b/hw/e1000.c
index 0da65f9a34..70aba11296 100644
--- a/hw/e1000.c
+++ b/hw/e1000.c
@@ -649,7 +649,6 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
}
rdh_start = s->mac_reg[RDH];
- size += 4; // for the header
do {
if (s->mac_reg[RDH] == s->mac_reg[RDT] && s->check_rxov) {
set_ics(s, 0, E1000_ICS_RXO);
@@ -663,7 +662,7 @@ e1000_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
if (desc.buffer_addr) {
cpu_physical_memory_write(le64_to_cpu(desc.buffer_addr),
(void *)(buf + vlan_offset), size);
- desc.length = cpu_to_le16(size);
+ desc.length = cpu_to_le16(size + 4 /* for FCS */);
desc.status |= E1000_RXD_STAT_EOP|E1000_RXD_STAT_IXSM;
} else // as per intel docs; skip descriptors with null buf addr
DBGOUT(RX, "Null RX descriptor!!\n");
--
2.30.2