From: Young Xiao <92siuyang@xxxxxxxxx> [ Upstream commit 385097a3675749cbc9e97c085c0e5dfe4269ca51 ] Check that the NFC_ATTR_TARGET_INDEX attributes (in addition to NFC_ATTR_DEVICE_INDEX) are provided by the netlink client prior to accessing them. This prevents potential unhandled NULL pointer dereference exceptions which can be triggered by malicious user-mode programs, if they omit one or both of these attributes. Signed-off-by: Young Xiao <92siuyang@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/nfc/netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/nfc/netlink.c +++ b/net/nfc/netlink.c @@ -922,7 +922,8 @@ static int nfc_genl_deactivate_target(st u32 device_idx, target_idx; int rc; - if (!info->attrs[NFC_ATTR_DEVICE_INDEX]) + if (!info->attrs[NFC_ATTR_DEVICE_INDEX] || + !info->attrs[NFC_ATTR_TARGET_INDEX]) return -EINVAL; device_idx = nla_get_u32(info->attrs[NFC_ATTR_DEVICE_INDEX]);
