Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net

Pull networking fixes from David Miller:

 1) Fix double-free in batman-adv, from Sven Eckelmann.

 2) Fix packet stats for fast-RX path, from Joannes Berg.

 3) Netfilter's ip_route_me_harder() doesn't handle request sockets
    properly, fix from Florian Westphal.

 4) Fix sendmsg deadlock in rxrpc, from David Howells.

 5) Add missing RCU locking to transport hashtable scan, from Xin Long.

 6) Fix potential packet loss in mlxsw driver, from Ido Schimmel.

 7) Fix race in NAPI handling between poll handlers and busy polling,
    from Eric Dumazet.

 8) TX path in vxlan and geneve need proper RCU locking, from Jakub
    Kicinski.

 9) SYN processing in DCCP and TCP need to disable BH, from Eric
    Dumazet.

10) Properly handle net_enable_timestamp() being invoked from IRQ
    context, also from Eric Dumazet.

11) Fix crash on device-tree systems in xgene driver, from Alban Bedel.

12) Do not call sk_free() on a locked socket, from Arnaldo Carvalho de
    Melo.

13) Fix use-after-free in netvsc driver, from Dexuan Cui.

14) Fix max MTU setting in bonding driver, from WANG Cong.

15) xen-netback hash table can be allocated from softirq context, so use
    GFP_ATOMIC. From Anoob Soman.

16) Fix MAC address change bug in bgmac driver, from Hari Vyas.

17) strparser needs to destroy strp_wq on module exit, from WANG Cong.

* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (69 commits)
  strparser: destroy workqueue on module exit
  sfc: fix IPID endianness in TSOv2
  sfc: avoid max() in array size
  rds: remove unnecessary returned value check
  rxrpc: Fix potential NULL-pointer exception
  nfp: correct DMA direction in XDP DMA sync
  nfp: don't tell FW about the reserved buffer space
  net: ethernet: bgmac: mac address change bug
  net: ethernet: bgmac: init sequence bug
  xen-netback: don't vfree() queues under spinlock
  xen-netback: keep a local pointer for vif in backend_disconnect()
  netfilter: nf_tables: don't call nfnetlink_set_err() if nfnetlink_send() fails
  netfilter: nft_set_rbtree: incorrect assumption on lower interval lookups
  netfilter: nf_conntrack_sip: fix wrong memory initialisation
  can: flexcan: fix typo in comment
  can: usb_8dev: Fix memory leak of priv->cmd_msg_buffer
  can: gs_usb: fix coding style
  can: gs_usb: Don't use stack memory for USB transfers
  ixgbe: Limit use of 2K buffers on architectures with 256B or larger cache lines
  ixgbe: update the rss key on h/w, when ethtool ask for it
  ...

1 files changed, 47 insertions, 11 deletions

diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index 19b36c60fb4c..bc2d3dcff9de 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -61,9 +61,12 @@ static int rxrpc_wait_for_tx_window(struct rxrpc_sock *rx,
 		}
 
 		trace_rxrpc_transmit(call, rxrpc_transmit_wait);
-		release_sock(&rx->sk);
+		mutex_unlock(&call->user_mutex);
 		*timeo = schedule_timeout(*timeo);
-		lock_sock(&rx->sk);
+		if (mutex_lock_interruptible(&call->user_mutex) < 0) {
+			ret = sock_intr_errno(*timeo);
+			break;
+		}
 	}
 
 	remove_wait_queue(&call->waitq, &myself);
@@ -173,7 +176,7 @@ static void rxrpc_queue_packet(struct rxrpc_call *call, struct sk_buff *skb,
 /*
  * send data through a socket
  * - must be called in process context
- * - caller holds the socket locked
+ * - The caller holds the call user access mutex, but not the socket lock.
  */
 static int rxrpc_send_data(struct rxrpc_sock *rx,
 			   struct rxrpc_call *call,
@@ -439,10 +442,13 @@ static int rxrpc_sendmsg_cmsg(struct msghdr *msg,
 
 /*
  * Create a new client call for sendmsg().
+ * - Called with the socket lock held, which it must release.
+ * - If it returns a call, the call's lock will need releasing by the caller.
  */
 static struct rxrpc_call *
 rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 				  unsigned long user_call_ID, bool exclusive)
+	__releases(&rx->sk.sk_lock.slock)
 {
 	struct rxrpc_conn_parameters cp;
 	struct rxrpc_call *call;
@@ -452,8 +458,10 @@ rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 
 	_enter("");
 
-	if (!msg->msg_name)
+	if (!msg->msg_name) {
+		release_sock(&rx->sk);
 		return ERR_PTR(-EDESTADDRREQ);
+	}
 
 	key = rx->key;
 	if (key && !rx->key->payload.data[0])
@@ -466,6 +474,7 @@ rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
 	cp.exclusive		= rx->exclusive | exclusive;
 	cp.service_id		= srx->srx_service;
 	call = rxrpc_new_client_call(rx, &cp, srx, user_call_ID, GFP_KERNEL);
+	/* The socket is now unlocked */
 
 	_leave(" = %p\n", call);
 	return call;
@@ -477,6 +486,7 @@ rxrpc_new_client_call_for_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg,
  * - the socket may be either a client socket or a server socket
  */
 int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
+	__releases(&rx->sk.sk_lock.slock)
 {
 	enum rxrpc_command cmd;
 	struct rxrpc_call *call;
@@ -490,12 +500,14 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 	ret = rxrpc_sendmsg_cmsg(msg, &user_call_ID, &cmd, &abort_code,
 				 &exclusive);
 	if (ret < 0)
-		return ret;
+		goto error_release_sock;
 
 	if (cmd == RXRPC_CMD_ACCEPT) {
+		ret = -EINVAL;
 		if (rx->sk.sk_state != RXRPC_SERVER_LISTENING)
-			return -EINVAL;
+			goto error_release_sock;
 		call = rxrpc_accept_call(rx, user_call_ID, NULL);
+		/* The socket is now unlocked. */
 		if (IS_ERR(call))
 			return PTR_ERR(call);
 		rxrpc_put_call(call, rxrpc_call_put);
@@ -504,12 +516,30 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 
 	call = rxrpc_find_call_by_user_ID(rx, user_call_ID);
 	if (!call) {
+		ret = -EBADSLT;
 		if (cmd != RXRPC_CMD_SEND_DATA)
-			return -EBADSLT;
+			goto error_release_sock;
 		call = rxrpc_new_client_call_for_sendmsg(rx, msg, user_call_ID,
 							 exclusive);
+		/* The socket is now unlocked... */
 		if (IS_ERR(call))
 			return PTR_ERR(call);
+		/* ... and we have the call lock. */
+	} else {
+		ret = -EBUSY;
+		if (call->state == RXRPC_CALL_UNINITIALISED ||
+		    call->state == RXRPC_CALL_CLIENT_AWAIT_CONN ||
+		    call->state == RXRPC_CALL_SERVER_PREALLOC ||
+		    call->state == RXRPC_CALL_SERVER_SECURING ||
+		    call->state == RXRPC_CALL_SERVER_ACCEPTING)
+			goto error_release_sock;
+
+		ret = mutex_lock_interruptible(&call->user_mutex);
+		release_sock(&rx->sk);
+		if (ret < 0) {
+			ret = -ERESTARTSYS;
+			goto error_put;
+		}
 	}
 
 	_debug("CALL %d USR %lx ST %d on CONN %p",
@@ -537,9 +567,15 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 		ret = rxrpc_send_data(rx, call, msg, len);
 	}
 
+	mutex_unlock(&call->user_mutex);
+error_put:
 	rxrpc_put_call(call, rxrpc_call_put);
 	_leave(" = %d", ret);
 	return ret;
+
+error_release_sock:
+	release_sock(&rx->sk);
+	return ret;
 }
 
 /**
@@ -564,7 +600,7 @@ int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 	ASSERTCMP(msg->msg_name, ==, NULL);
 	ASSERTCMP(msg->msg_control, ==, NULL);
 
-	lock_sock(sock->sk);
+	mutex_lock(&call->user_mutex);
 
 	_debug("CALL %d USR %lx ST %d on CONN %p",
 	       call->debug_id, call->user_call_ID, call->state, call->conn);
@@ -579,7 +615,7 @@ int rxrpc_kernel_send_data(struct socket *sock, struct rxrpc_call *call,
 		ret = rxrpc_send_data(rxrpc_sk(sock->sk), call, msg, len);
 	}
 
-	release_sock(sock->sk);
+	mutex_unlock(&call->user_mutex);
 	_leave(" = %d", ret);
 	return ret;
 }
@@ -600,12 +636,12 @@ void rxrpc_kernel_abort_call(struct socket *sock, struct rxrpc_call *call,
 {
 	_enter("{%d},%d,%d,%s", call->debug_id, abort_code, error, why);
 
-	lock_sock(sock->sk);
+	mutex_lock(&call->user_mutex);
 
 	if (rxrpc_abort_call(why, call, 0, abort_code, error))
 		rxrpc_send_abort_packet(call);
 
-	release_sock(sock->sk);
+	mutex_unlock(&call->user_mutex);
 	_leave("");
 }