nfc: Ensure presence of required attributes in the deactivate_target …

…handler 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]> Signed-off-by: David S. Miller <[email protected]>
niw · Jun 14, 2019 · 385097a · 385097a
1 parent b8003ce
commit 385097a
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/net/nfc/netlink.c b/net/nfc/netlink.c
@@ -911,7 +911,8 @@ 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]);