[PATCH 7/11] drivers/scsi: Eliminate a NULL pointer dereference

From: Julia Lawall
Date: Thu May 27 2010 - 08:33:59 EST


From: Julia Lawall <julia@xxxxxxx>

The end of the function is reachable both when host is and is not NULL.

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

// <smpl>
@r exists@
expression E,E1;
identifier f;
statement S1,S2,S3;
@@

if ((E == NULL && ...) || ...)
{
... when != if (...) S1 else S2
when != E = E1
* E->f
... when any
return ...;
}
else S3
// </smpl>

Signed-off-by: Julia Lawall <julia@xxxxxxx>

---
If it is a problem to use 0 when host is NULL, then the code could be fixed
in another way.

drivers/scsi/hptiop.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/hptiop.c b/drivers/scsi/hptiop.c
index 645f7cd..0729f15 100644
--- a/drivers/scsi/hptiop.c
+++ b/drivers/scsi/hptiop.c
@@ -1157,7 +1157,7 @@ free_pci_regions:
disable_pci_device:
pci_disable_device(pcidev);

- dprintk("scsi%d: hptiop_probe fail\n", host->host_no);
+ dprintk("scsi%d: hptiop_probe fail\n", host ? host->host_no : 0);
return -ENODEV;
}

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/