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()

1 files changed, 14 insertions, 3 deletions

diff --git a/fs/afs/server.c b/fs/afs/server.c
index 65b33b6da48b..52c170b59cfd 100644
--- a/fs/afs/server.c
+++ b/fs/afs/server.c
@@ -521,8 +521,15 @@ static noinline bool afs_update_server_record(struct afs_fs_cursor *fc, struct a
 	alist = afs_vl_lookup_addrs(fc->vnode->volume->cell, fc->key,
 				    &server->uuid);
 	if (IS_ERR(alist)) {
-		fc->ac.error = PTR_ERR(alist);
-		_leave(" = f [%d]", fc->ac.error);
+		if ((PTR_ERR(alist) == -ERESTARTSYS ||
+		     PTR_ERR(alist) == -EINTR) &&
+		    !(fc->flags & AFS_FS_CURSOR_INTR) &&
+		    server->addresses) {
+			_leave(" = t [intr]");
+			return true;
+		}
+		fc->error = PTR_ERR(alist);
+		_leave(" = f [%d]", fc->error);
 		return false;
 	}
 
@@ -574,7 +581,11 @@ retry:
 	ret = wait_on_bit(&server->flags, AFS_SERVER_FL_UPDATING,
 			  TASK_INTERRUPTIBLE);
 	if (ret == -ERESTARTSYS) {
-		fc->ac.error = ret;
+		if (!(fc->flags & AFS_FS_CURSOR_INTR) && server->addresses) {
+			_leave(" = t [intr]");
+			return true;
+		}
+		fc->error = ret;
 		_leave(" = f [intr]");
 		return false;
 	}