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Subject[10/17] SCSI: aacraid: Eliminate use after free
2.6.27-stable review patch.  If anyone has any objections, please let us know.

------------------
From: Julia Lawall <julia@diku.dk>

commit 8a52da632ceb9d8b776494563df579e87b7b586b upstream.

The debugging code using the freed structure is moved before the kfree.

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

// <smpl>
@free@
expression E;
position p;
@@
kfree@p(E)

@@
expression free.E, subE<=free.E, E1;
position free.p;
@@

kfree@p(E)
...
(
subE = E1
|
* E
)
// </smpl>

Signed-off-by: Julia Lawall <julia@diku.dk>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

---
drivers/scsi/aacraid/commctrl.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/scsi/aacraid/commctrl.c
+++ b/drivers/scsi/aacraid/commctrl.c
@@ -645,9 +645,9 @@ static int aac_send_raw_srb(struct aac_d
/* Does this really need to be GFP_DMA? */
p = kmalloc(usg->sg[i].count,GFP_KERNEL|__GFP_DMA);
if(!p) {
- kfree (usg);
- dprintk((KERN_DEBUG"aacraid: Could not allocate SG buffer - size = %d buffer number %d of %d\n",
+ dprintk((KERN_DEBUG "aacraid: Could not allocate SG buffer - size = %d buffer number %d of %d\n",
usg->sg[i].count,i,usg->count));
+ kfree(usg);
rcode = -ENOMEM;
goto cleanup;
}



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