mtd: maps: Eliminate use after free

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Gitweb:     http://git.infradead.org/?p=mtd-2.6.git;a=commit;h=258006d1abcf3f2990d3ebd77d75af335ff24d81
Commit:     258006d1abcf3f2990d3ebd77d75af335ff24d81
Parent:     c4e773764cead9358fd4b036d1b883fff3968513
Author:     Julia Lawall <julia at diku.dk>
AuthorDate: Fri Apr 2 14:47:38 2010 +0200
Committer:  David Woodhouse <David.Woodhouse at intel.com>
CommitDate: Mon May 10 14:22:55 2010 +0100

    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 at diku.dk>
    Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy at nokia.com>
    Signed-off-by: David Woodhouse <David.Woodhouse at intel.com>
---
 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 689d6a7..81159d7 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);