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 <[email protected]> --- net/nfc/netlink.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c index 04a8e47..89d885d 100644 --- a/net/nfc/netlink.c +++ b/net/nfc/netlink.c @@ -923,7 +923,8 @@ static int nfc_genl_deactivate_target(struct sk_buff *skb, 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]); -- 2.7.4
