From: Alan Tull <atull@kernel.org>
Date: Wed, 12 Sep 2018 14:43:23 +0000 (-0500)
Subject: fpga: do not access region struct after fpga_region_unregister
X-Git-Tag: v4.19-rc7~1^2~6
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=34bd283396af1f05c43fa64d51378d38affb1cf1;p=users%2Fhch%2Fblock.git

fpga: do not access region struct after fpga_region_unregister

A couple drivers were accessing the region struct after it had been
freed.  Save off the pointer to the mgr before the region struct gets
freed.

Signed-off-by: Alan Tull <atull@kernel.org>
Acked-by: Moritz Fischer <mdf@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/drivers/fpga/dfl-fme-region.c b/drivers/fpga/dfl-fme-region.c
index 0b7e19c27c6d..51a5ac2293a7 100644
--- a/drivers/fpga/dfl-fme-region.c
+++ b/drivers/fpga/dfl-fme-region.c
@@ -14,6 +14,7 @@
  */
 
 #include <linux/module.h>
+#include <linux/fpga/fpga-mgr.h>
 #include <linux/fpga/fpga-region.h>
 
 #include "dfl-fme-pr.h"
@@ -66,9 +67,10 @@ eprobe_mgr_put:
 static int fme_region_remove(struct platform_device *pdev)
 {
 	struct fpga_region *region = dev_get_drvdata(&pdev->dev);
+	struct fpga_manager *mgr = region->mgr;
 
 	fpga_region_unregister(region);
-	fpga_mgr_put(region->mgr);
+	fpga_mgr_put(mgr);
 
 	return 0;
 }
diff --git a/drivers/fpga/of-fpga-region.c b/drivers/fpga/of-fpga-region.c
index 35fabb8083fb..052a1342ab7e 100644
--- a/drivers/fpga/of-fpga-region.c
+++ b/drivers/fpga/of-fpga-region.c
@@ -437,9 +437,10 @@ eprobe_mgr_put:
 static int of_fpga_region_remove(struct platform_device *pdev)
 {
 	struct fpga_region *region = platform_get_drvdata(pdev);
+	struct fpga_manager *mgr = region->mgr;
 
 	fpga_region_unregister(region);
-	fpga_mgr_put(region->mgr);
+	fpga_mgr_put(mgr);
 
 	return 0;
 }