CacheFiles: Update IMA counters when using dentry_open

When IMA is active, using dentry_open without updating the
IMA counters will result in free/open imbalance errors when
fput is eventually called.

Signed-off-by: Marc Dionne <marc.c.dionne@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/cachefiles/rdwr.c b/fs/cachefiles/rdwr.c
index 1d83325..a6c8c6f 100644
--- a/fs/cachefiles/rdwr.c
+++ b/fs/cachefiles/rdwr.c
@@ -11,6 +11,7 @@
 
 #include <linux/mount.h>
 #include <linux/file.h>
+#include <linux/ima.h>
 #include "internal.h"
 
 /*
@@ -922,6 +923,7 @@
 	if (IS_ERR(file)) {
 		ret = PTR_ERR(file);
 	} else {
+		ima_counts_get(file);
 		ret = -EIO;
 		if (file->f_op->write) {
 			pos = (loff_t) page->index << PAGE_SHIFT;