From: Xiaoming Ni <nixiaoming@xxxxxxxxxx> commit 7574fcdbdcb335763b6b322f6928dc0fd5730451 upstream. In llcp_sock_connect(), use kmemdup to allocate memory for "llcp_sock->service_name". The memory is not released in the sock_unlink label of the subsequent failure branch. As a result, memory leakage occurs. fix CVE-2020-25672 Fixes: d646960f7986 ("NFC: Initial LLCP support") Reported-by: "kiyin(尹亮)" <kiyin@xxxxxxxxxxx> Link: https://www.openwall.com/lists/oss-security/2020/11/01/1 Cc: <stable@xxxxxxxxxxxxxxx> #v3.3 Signed-off-by: Xiaoming Ni <nixiaoming@xxxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/nfc/llcp_sock.c | 2 ++ 1 file changed, 2 insertions(+) --- a/net/nfc/llcp_sock.c +++ b/net/nfc/llcp_sock.c @@ -751,6 +751,8 @@ sock_unlink: nfc_llcp_local_put(llcp_sock->local); nfc_llcp_sock_unlink(&local->connecting_sockets, sk); + kfree(llcp_sock->service_name); + llcp_sock->service_name = NULL; put_dev: nfc_put_device(dev);