From: Prasad J Pandit Date: Fri, 15 Jan 2016 07:00:40 +0000 (+0530) Subject: net: cadence_gem: check packet size in gem_recieve X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=a136dd80ade511360d1cec99554c5e160cbd64af;p=qemu-upstream-4.5-testing.git 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 --- diff --git a/hw/net/cadence_gem.c b/hw/net/cadence_gem.c index 92dc2f21f..76e4ea0ad 100644 --- a/hw/net/cadence_gem.c +++ b/hw/net/cadence_gem.c @@ -719,6 +719,10 @@ static ssize_t gem_receive(NetClientState *nc, const uint8_t *buf, size_t size) unsigned crc_val; int crc_offset; + 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 caclculate one. */