From: 黄涛 <huangtao@rock-chips.com>
Date: Tue, 13 Dec 2011 04:05:20 +0000 (+0800)
Subject: pmem: fix pass miscdevice pointer via file private data
X-Git-Tag: firefly_0821_release~9712^2~7
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=e438d11cd2637cd5c8da0915b3eb625b0f77b6bf;p=firefly-linux-kernel-4.4.55.git

pmem: fix pass miscdevice pointer via file private data
---

diff --git a/drivers/misc/pmem.c b/drivers/misc/pmem.c
index b47acd333f35..5b8b6bdbc87d 100644
--- a/drivers/misc/pmem.c
+++ b/drivers/misc/pmem.c
@@ -337,7 +337,7 @@ static int pmem_open(struct inode *inode, struct file *file)
 	DLOG("current %u file %p(%d)\n", current->pid, file, file_count(file));
 	/* setup file->private_data to indicate its unmapped */
 	/*  you can only open a pmem device one time */
-	if (file->private_data != NULL)
+	if (file->private_data != NULL && file->private_data != &pmem[id].dev)
 		return -1;
 	data = kmalloc(sizeof(struct pmem_data), GFP_KERNEL);
 	if (!data) {