From: Julia Lawall <julia@diku.dk>
Date: Fri, 2 Apr 2010 12:47:38 +0000 (+0200)
Subject: mtd: maps: Eliminate use after free
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=258006d1abcf3f2990d3ebd77d75af335ff24d81;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

mtd: maps: Eliminate use after free

Moved the debugging message before the call to map_destroy, which frees its
argument.  The message is also slightly changed to reflect its new
position.

A simplified version of the semantic patch that finds this problem is as
follows: (http://coccinelle.lip6.fr/)

// <smpl>
@@
expression E,E2;
@@

del_mtd_device(E)
...
(
  E = E2
|
* E
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com>
Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
---

diff --git a/drivers/mtd/maps/pcmciamtd.c b/drivers/mtd/maps/pcmciamtd.c
index 689d6a79ffc0..81159d708f86 100644
--- a/drivers/mtd/maps/pcmciamtd.c
+++ b/drivers/mtd/maps/pcmciamtd.c
@@ -692,8 +692,8 @@ static void pcmciamtd_detach(struct pcmcia_device *link)
 
 	if(dev->mtd_info) {
 		del_mtd_device(dev->mtd_info);
+		info("mtd%d: Removing", dev->mtd_info->index);
 		map_destroy(dev->mtd_info);
-		info("mtd%d: Removed", dev->mtd_info->index);
 	}
 
 	pcmciamtd_release(link);