mptcp: avoid lock_fast usage in accept path

Once event support is added this may need to allocate memory while msk lock is held with softirqs disabled. Not using lock_fast also allows to do the allocation with GFP_KERNEL. Reviewed-by: Mat Martineau <[email protected]> Signed-off-by: Florian Westphal <[email protected]>
multipath-tcp · Feb 2, 2021 · 875cda9 · 875cda9
1 parent d30f162
commit 875cda9
Showing 1 changed file with 2 additions and 3 deletions.
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c
@@ -3256,9 +3256,8 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock,
 		struct mptcp_sock *msk = mptcp_sk(newsock->sk);
 		struct mptcp_subflow_context *subflow;
 		struct sock *newsk = newsock->sk;
-		bool slowpath;
 
-		slowpath = lock_sock_fast(newsk);
+		lock_sock(newsk);
 
 		/* PM/worker can now acquire the first subflow socket
 		 * lock without racing with listener queue cleanup,
@@ -3284,7 +3283,7 @@ static int mptcp_stream_accept(struct socket *sock, struct socket *newsock,
 			if (!ssk->sk_socket)
 				mptcp_sock_graft(ssk, newsock);
 		}
-		unlock_sock_fast(newsk, slowpath);
+		release_sock(newsk);
 	}
 
 	if (inet_csk_listen_poll(ssock->sk))