From 7b57f9d78b84483818a3faf34dad628b3bdc6a5b Mon Sep 17 00:00:00 2001 From: Prasad J Pandit Date: Fri, 15 Jan 2016 12:30:40 +0530 Subject: [PATCH] net: cadence_gem: check packet size in gem_recieve While receiving packets in 'gem_receive' routine, if Frame Check Sequence(FCS) is enabled, it copies the packet into a local buffer without checking its size. Add check to validate packet length against the buffer size to avoid buffer overflow. Reported-by: Ling Liu Signed-off-by: Prasad J Pandit Signed-off-by: Jason Wang --- hw/net/cadence_gem.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c index de26609c9..01534cf08 100644 --- a/hw/net/cadence_gem.c +++ b/hw/net/cadence_gem.c @@ -718,6 +718,10 @@ static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size) } else { unsigned crc_val; + if (size > sizeof(rxbuf) - sizeof(crc_val)) { + size = sizeof(rxbuf) - sizeof(crc_val); + } + bytes_to_copy = size; /* The application wants the FCS field, which QEMU does not provide. * We must try and calculate one. */ -- 2.39.5