From 8a52da632ceb9d8b776494563df579e87b7b586b Mon Sep 17 00:00:00 2001 From: Julia Lawall Date: Sat, 15 May 2010 11:46:12 +0200 Subject: [PATCH] [SCSI] aacraid: Eliminate use after free 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/) // @free@ expression E; position p; @@ kfree@p(E) @@ expression free.E, subE<=free.E, E1; position free.p; @@ kfree@p(E) ... ( subE = E1 | * E ) // Signed-off-by: Julia Lawall Signed-off-by: James Bottomley --- drivers/scsi/aacraid/commctrl.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/scsi/aacraid/commctrl.c b/drivers/scsi/aacraid/commctrl.c index 9c0c91178538..1a5bf5724750 100644 --- a/drivers/scsi/aacraid/commctrl.c +++ b/drivers/scsi/aacraid/commctrl.c @@ -655,9 +655,9 @@ static int aac_send_raw_srb(struct aac_dev* dev, void __user * arg) /* 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; } -- 2.20.1