From: Prasad J Pandit <p...@fedoraproject.org> When receiving packets over Stellaris ethernet controller, it uses receive buffer of size 2048 bytes. In case the controller accepts large(MTU) packets, it could lead to memory corruption. Add check to avoid it.
Reported by: Oleksandr Bazhaniuk <oleksandr.bazhan...@intel.com> Signed-off-by: Prasad J Pandit <p...@fedoraproject.org> --- hw/net/stellaris_enet.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) Update per review: -> https://lists.gnu.org/archive/html/qemu-devel/2016-04/msg01142.html diff --git a/hw/net/stellaris_enet.c b/hw/net/stellaris_enet.c index 21a4773..eddbe60 100644 --- a/hw/net/stellaris_enet.c +++ b/hw/net/stellaris_enet.c @@ -235,8 +235,16 @@ static ssize_t stellaris_enet_receive(NetClientState *nc, const uint8_t *buf, si n = s->next_packet + s->np; if (n >= 31) n -= 31; + if (size >= sizeof(s->rx[n].data) - 6) { + /* If the packet won't fit into the + * emulated 2K RAM, this is reported + * as a FIFO overrun error. + */ + s->ris |= SE_INT_FOV; + stellaris_enet_update(s); + return -1; + } s->np++; - s->rx[n].len = size + 6; p = s->rx[n].data; *(p++) = (size + 6); -- 2.5.5
