Merge tag 'afs-fixes-20190516' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs

Pull misc AFS fixes from David Howells:
 "This fixes a set of miscellaneous issues in the afs filesystem,
  including:

   - leak of keys on file close.

   - broken error handling in xattr functions.

   - missing locking when updating VL server list.

   - volume location server DNS lookup whereby preloaded cells may not
     ever get a lookup and regular DNS lookups to maintain server lists
     consume power unnecessarily.

   - incorrect error propagation and handling in the fileserver
     iteration code causes operations to sometimes apparently succeed.

   - interruption of server record check/update side op during
     fileserver iteration causes uninterruptible main operations to fail
     unexpectedly.

   - callback promise expiry time miscalculation.

   - over invalidation of the callback promise on directories.

   - double locking on callback break waking up file locking waiters.

   - double increment of the vnode callback break counter.

  Note that it makes some changes outside of the afs code, including:

   - an extra parameter to dns_query() to allow the dns_resolver key
     just accessed to be immediately invalidated. AFS is caching the
     results itself, so the key can be discarded.

   - an interruptible version of wait_var_event().

   - an rxrpc function to allow the maximum lifespan to be set on a
     call.

   - a way for an rxrpc call to be marked as non-interruptible"

* tag 'afs-fixes-20190516' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
  afs: Fix double inc of vnode->cb_break
  afs: Fix lock-wait/callback-break double locking
  afs: Don't invalidate callback if AFS_VNODE_DIR_VALID not set
  afs: Fix calculation of callback expiry time
  afs: Make dynamic root population wait uninterruptibly for proc_cells_lock
  afs: Make some RPC operations non-interruptible
  rxrpc: Allow the kernel to mark a call as being non-interruptible
  afs: Fix error propagation from server record check/update
  afs: Fix the maximum lifespan of VL and probe calls
  rxrpc: Provide kernel interface to set max lifespan on a call
  afs: Fix "kAFS: AFS vnode with undefined type 0"
  afs: Fix cell DNS lookup
  Add wait_var_event_interruptible()
  dns_resolver: Allow used keys to be invalidated
  afs: Fix afs_cell records to always have a VL server list record
  afs: Fix missing lock when replacing VL server list
  afs: Fix afs_xattr_get_yfs() to not try freeing an error value
  afs: Fix incorrect error handling in afs_xattr_get_acl()
  afs: Fix key leak in afs_release() and afs_evict_inode()

7 files changed, 47 insertions, 5 deletions

diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 3ee380758ddd..cd0b094468b6 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -1887,7 +1887,7 @@ static int ceph_dns_resolve_name(const char *name, size_t namelen,
 		return -EINVAL;
 
 	/* do dns_resolve upcall */
-	ip_len = dns_query(NULL, name, end - name, NULL, &ip_addr, NULL);
+	ip_len = dns_query(NULL, name, end - name, NULL, &ip_addr, NULL, false);
 	if (ip_len > 0)
 		ret = ceph_pton(ip_addr, ip_len, addr, -1, NULL);
 	else
diff --git a/net/dns_resolver/dns_query.c b/net/dns_resolver/dns_query.c
index 19aa32fc1802..2d260432b3be 100644
--- a/net/dns_resolver/dns_query.c
+++ b/net/dns_resolver/dns_query.c
@@ -54,6 +54,7 @@
  * @options: Request options (or NULL if no options)
  * @_result: Where to place the returned data (or NULL)
  * @_expiry: Where to store the result expiry time (or NULL)
+ * @invalidate: Always invalidate the key after use
  *
  * The data will be returned in the pointer at *result, if provided, and the
  * caller is responsible for freeing it.
@@ -69,7 +70,8 @@
  * Returns the size of the result on success, -ve error code otherwise.
  */
 int dns_query(const char *type, const char *name, size_t namelen,
-	      const char *options, char **_result, time64_t *_expiry)
+	      const char *options, char **_result, time64_t *_expiry,
+	      bool invalidate)
 {
 	struct key *rkey;
 	struct user_key_payload *upayload;
@@ -157,6 +159,8 @@ int dns_query(const char *type, const char *name, size_t namelen,
 	ret = len;
 put:
 	up_read(&rkey->sem);
+	if (invalidate)
+		key_invalidate(rkey);
 	key_put(rkey);
 out:
 	kleave(" = %d", ret);
diff --git a/net/rxrpc/af_rxrpc.c b/net/rxrpc/af_rxrpc.c
index ae8c5d7f3bf1..ffde5b187f5d 100644
--- a/net/rxrpc/af_rxrpc.c
+++ b/net/rxrpc/af_rxrpc.c
@@ -270,6 +270,7 @@ static int rxrpc_listen(struct socket *sock, int backlog)
  * @gfp: The allocation constraints
  * @notify_rx: Where to send notifications instead of socket queue
  * @upgrade: Request service upgrade for call
+ * @intr: The call is interruptible
  * @debug_id: The debug ID for tracing to be assigned to the call
  *
  * Allow a kernel service to begin a call on the nominated socket.  This just
@@ -287,6 +288,7 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 					   gfp_t gfp,
 					   rxrpc_notify_rx_t notify_rx,
 					   bool upgrade,
+					   bool intr,
 					   unsigned int debug_id)
 {
 	struct rxrpc_conn_parameters cp;
@@ -311,6 +313,7 @@ struct rxrpc_call *rxrpc_kernel_begin_call(struct socket *sock,
 	memset(&p, 0, sizeof(p));
 	p.user_call_ID = user_call_ID;
 	p.tx_total_len = tx_total_len;
+	p.intr = intr;
 
 	memset(&cp, 0, sizeof(cp));
 	cp.local		= rx->local;
@@ -443,6 +446,31 @@ void rxrpc_kernel_new_call_notification(
 }
 EXPORT_SYMBOL(rxrpc_kernel_new_call_notification);
 
+/**
+ * rxrpc_kernel_set_max_life - Set maximum lifespan on a call
+ * @sock: The socket the call is on
+ * @call: The call to configure
+ * @hard_timeout: The maximum lifespan of the call in jiffies
+ *
+ * Set the maximum lifespan of a call.  The call will end with ETIME or
+ * ETIMEDOUT if it takes longer than this.
+ */
+void rxrpc_kernel_set_max_life(struct socket *sock, struct rxrpc_call *call,
+			       unsigned long hard_timeout)
+{
+	unsigned long now;
+
+	mutex_lock(&call->user_mutex);
+
+	now = jiffies;
+	hard_timeout += now;
+	WRITE_ONCE(call->expect_term_by, hard_timeout);
+	rxrpc_reduce_call_timer(call, hard_timeout, now, rxrpc_timer_set_for_hard);
+
+	mutex_unlock(&call->user_mutex);
+}
+EXPORT_SYMBOL(rxrpc_kernel_set_max_life);
+
 /*
  * connect an RxRPC socket
  * - this just targets it at a specific destination; no actual connection
diff --git a/net/rxrpc/ar-internal.h b/net/rxrpc/ar-internal.h
index 062ca9dc29b8..07fc1dfa4878 100644
--- a/net/rxrpc/ar-internal.h
+++ b/net/rxrpc/ar-internal.h
@@ -482,6 +482,7 @@ enum rxrpc_call_flag {
 	RXRPC_CALL_BEGAN_RX_TIMER,	/* We began the expect_rx_by timer */
 	RXRPC_CALL_RX_HEARD,		/* The peer responded at least once to this call */
 	RXRPC_CALL_RX_UNDERRUN,		/* Got data underrun */
+	RXRPC_CALL_IS_INTR,		/* The call is interruptible */
 };
 
 /*
@@ -711,6 +712,7 @@ struct rxrpc_call_params {
 		u32		normal;		/* Max time since last call packet (msec) */
 	} timeouts;
 	u8			nr_timeouts;	/* Number of timeouts specified */
+	bool			intr;		/* The call is interruptible */
 };
 
 struct rxrpc_send_params {
diff --git a/net/rxrpc/call_object.c b/net/rxrpc/call_object.c
index fe96881a334d..d0ca98d7aef5 100644
--- a/net/rxrpc/call_object.c
+++ b/net/rxrpc/call_object.c
@@ -241,6 +241,8 @@ struct rxrpc_call *rxrpc_new_client_call(struct rxrpc_sock *rx,
 		return call;
 	}
 
+	if (p->intr)
+		__set_bit(RXRPC_CALL_IS_INTR, &call->flags);
 	call->tx_total_len = p->tx_total_len;
 	trace_rxrpc_call(call, rxrpc_call_new_client, atomic_read(&call->usage),
 			 here, (const void *)p->user_call_ID);
diff --git a/net/rxrpc/conn_client.c b/net/rxrpc/conn_client.c
index 83797b3949e2..5cf5595a14d8 100644
--- a/net/rxrpc/conn_client.c
+++ b/net/rxrpc/conn_client.c
@@ -656,10 +656,14 @@ static int rxrpc_wait_for_channel(struct rxrpc_call *call, gfp_t gfp)
 
 		add_wait_queue_exclusive(&call->waitq, &myself);
 		for (;;) {
-			set_current_state(TASK_INTERRUPTIBLE);
+			if (test_bit(RXRPC_CALL_IS_INTR, &call->flags))
+				set_current_state(TASK_INTERRUPTIBLE);
+			else
+				set_current_state(TASK_UNINTERRUPTIBLE);
 			if (call->call_id)
 				break;
-			if (signal_pending(current)) {
+			if (test_bit(RXRPC_CALL_IS_INTR, &call->flags) &&
+			    signal_pending(current)) {
 				ret = -ERESTARTSYS;
 				break;
 			}
diff --git a/net/rxrpc/sendmsg.c b/net/rxrpc/sendmsg.c
index bec64deb7b0a..45a05d9a27fa 100644
--- a/net/rxrpc/sendmsg.c
+++ b/net/rxrpc/sendmsg.c
@@ -80,7 +80,8 @@ static int rxrpc_wait_for_tx_window_nonintr(struct rxrpc_sock *rx,
 		if (call->state >= RXRPC_CALL_COMPLETE)
 			return call->error;
 
-		if (timeout == 0 &&
+		if (test_bit(RXRPC_CALL_IS_INTR, &call->flags) &&
+		    timeout == 0 &&
 		    tx_win == tx_start && signal_pending(current))
 			return -EINTR;
 
@@ -620,6 +621,7 @@ int rxrpc_do_sendmsg(struct rxrpc_sock *rx, struct msghdr *msg, size_t len)
 		.call.tx_total_len	= -1,
 		.call.user_call_ID	= 0,
 		.call.nr_timeouts	= 0,
+		.call.intr		= true,
 		.abort_code		= 0,
 		.command		= RXRPC_CMD_SEND_DATA,
 		.exclusive		= false,