[net-next,v6,2/2] nfc: Do not send datagram if socket state isn't LLCP_BOUND

Message ID c4e2435c57cff7f650c0a82c2ded12c0d1843b80.1702816635.git.code@siddh.me
State New
Headers
Series nfc: Fix UAF during datagram sending caused by missing refcounting |

Commit Message

Siddh Raman Pant Dec. 17, 2023, 1:11 p.m. UTC
  As we know we cannot send the datagram (state can be set to LLCP_CLOSED
by nfc_llcp_socket_release()), there is no need to proceed further.

Thus, bail out early from llcp_sock_sendmsg().

Signed-off-by: Siddh Raman Pant <code@siddh.me>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
Reviewed-by: Suman Ghosh <sumang@marvell.com>
---
 net/nfc/llcp_sock.c | 5 +++++
 1 file changed, 5 insertions(+)
  

Patch

diff --git a/net/nfc/llcp_sock.c b/net/nfc/llcp_sock.c
index 645677f84dba..819157bbb5a2 100644
--- a/net/nfc/llcp_sock.c
+++ b/net/nfc/llcp_sock.c
@@ -796,6 +796,11 @@  static int llcp_sock_sendmsg(struct socket *sock, struct msghdr *msg,
 	}
 
 	if (sk->sk_type == SOCK_DGRAM) {
+		if (sk->sk_state != LLCP_BOUND) {
+			release_sock(sk);
+			return -ENOTCONN;
+		}
+
 		DECLARE_SOCKADDR(struct sockaddr_nfc_llcp *, addr,
 				 msg->msg_name);