2010-04-02 12:47:47

by Julia Lawall

Subject: [PATCH 2/3] drivers/mtd/maps: Eliminate use after free

From: Julia Lawall <[email protected]>

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 <[email protected]>

---
drivers/mtd/maps/pcmciamtd.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/mtd/maps/pcmciamtd.c b/drivers/mtd/maps/pcmciamtd.c
index 87b2b8f..3e339de 100644
--- a/drivers/mtd/maps/pcmciamtd.c
+++ b/drivers/mtd/maps/pcmciamtd.c
@@ -689,8 +689,8 @@ 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);

2010-04-27 07:24:51

by Artem Bityutskiy

Subject: Re: [PATCH 2/3] drivers/mtd/maps: Eliminate use after free

On Fri, 2010-04-02 at 14:47 +0200, Julia Lawall wrote:
> From: Julia Lawall <[email protected]>
>
> 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/)

Pushed to l2-mtd-2.6.git, thanks.

--
Best Regards,
Artem Bityutskiy (Артём Битюцкий)