Lack of validation could lead to out-of-bound reads and information leaks (cf. usage of nvdev->chan_table[]). Check that the number of allocated sub-channels fits into the expected range. Suggested-by: Saruhan Karademir <skarade@xxxxxxxxxxxxx> Signed-off-by: Andrea Parri (Microsoft) <parri.andrea@xxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Jakub Kicinski <kuba@xxxxxxxxxx> Cc: netdev@xxxxxxxxxxxxxxx --- Based on hyperv-next. drivers/net/hyperv/rndis_filter.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/drivers/net/hyperv/rndis_filter.c b/drivers/net/hyperv/rndis_filter.c index 3835d9bea1005..c5a709f67870f 100644 --- a/drivers/net/hyperv/rndis_filter.c +++ b/drivers/net/hyperv/rndis_filter.c @@ -1226,6 +1226,11 @@ int rndis_set_subchannel(struct net_device *ndev, return -EIO; } + /* Check that number of allocated sub channel is within the expected range */ + if (init_packet->msg.v5_msg.subchn_comp.num_subchannels > nvdev->num_chn - 1) { + netdev_err(ndev, "invalid number of allocated sub channel\n"); + return -EINVAL; + } nvdev->num_chn = 1 + init_packet->msg.v5_msg.subchn_comp.num_subchannels; -- 2.25.1