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()

Documentation/networking/rxrpc.txt

@@ -796,7 +796,9 @@ The kernel interface functions are as follows:
 				s64 tx_total_len,
 				gfp_t gfp,
 				rxrpc_notify_rx_t notify_rx,
-				bool upgrade);
+				bool upgrade,
+				bool intr,
+				unsigned int debug_id);
 
      This allocates the infrastructure to make a new RxRPC call and assigns
      call and connection numbers.  The call will be made on the UDP port that
@@ -824,6 +826,13 @@ The kernel interface functions are as follows:
      the server upgrade the service to a better one.  The resultant service ID
      is returned by rxrpc_kernel_recv_data().
 
+     intr should be set to true if the call should be interruptible.  If this
+     is not set, this function may not return until a channel has been
+     allocated; if it is set, the function may return -ERESTARTSYS.
+
+     debug_id is the call debugging ID to be used for tracing.  This can be
+     obtained by atomically incrementing rxrpc_debug_id.
+
      If this function is successful, an opaque reference to the RxRPC call is
      returned.  The caller now holds a reference on this and it must be
      properly ended.
@@ -1056,6 +1065,16 @@ The kernel interface functions are as follows:
      This value can be used to determine if the remote client has been
      restarted as it shouldn't change otherwise.
 
+ (*) Set the maxmimum lifespan on a call.
+
+	void rxrpc_kernel_set_max_life(struct socket *sock,
+				       struct rxrpc_call *call,
+				       unsigned long hard_timeout)
+
+     This sets the maximum lifespan on a call to hard_timeout (which is in
+     jiffies).  In the event of the timeout occurring, the call will be
+     aborted and -ETIME or -ETIMEDOUT will be returned.
+
 
 =======================
 CONFIGURABLE PARAMETERS

fs/afs/addr_list.c

@@ -251,7 +251,7 @@ struct afs_vlserver_list *afs_dns_query(struct afs_cell *cell, time64_t *_expiry
 	_enter("%s", cell->name);
 
 	ret = dns_query("afsdb", cell->name, cell->name_len, "srv=1",
-			&result, _expiry);
+			&result, _expiry, true);
 	if (ret < 0) {
 		_leave(" = %d [dns]", ret);
 		return ERR_PTR(ret);

fs/afs/afs.h

@@ -23,6 +23,9 @@
 #define AFSPATHMAX		1024	/* Maximum length of a pathname plus NUL */
 #define AFSOPAQUEMAX		1024	/* Maximum length of an opaque field */
 
+#define AFS_VL_MAX_LIFESPAN	(120 * HZ)
+#define AFS_PROBE_MAX_LIFESPAN	(30 * HZ)
+
 typedef u64			afs_volid_t;
 typedef u64			afs_vnodeid_t;
 typedef u64			afs_dataversion_t;

fs/afs/callback.c

@@ -218,14 +218,8 @@ void __afs_break_callback(struct afs_vnode *vnode)
 		vnode->cb_break++;
 		afs_clear_permits(vnode);
 
-		spin_lock(&vnode->lock);
-
-		_debug("break callback");
-
-		if (list_empty(&vnode->granted_locks) &&
-		    !list_empty(&vnode->pending_locks))
+		if (vnode->lock_state == AFS_VNODE_LOCK_WAITING_FOR_CB)
 			afs_lock_may_be_available(vnode);
-		spin_unlock(&vnode->lock);
 	}
 }