[PATCH 03/22] scsi: mpt3sas: fix format overflow warning

From: Arnd Bergmann
Date: Fri Jul 14 2017 - 08:10:03 EST


We print the driver name into one string and then add and ID
and copy it into a second string of the same length, at which
point gcc complains about a possible overflow:

drivers/scsi/mpt3sas/mpt3sas_scsih.c: In function '_scsih_probe':
drivers/scsi/mpt3sas/mpt3sas_scsih.c:8884:21: error: '_cm' directive writing 3 bytes into a region of size between 1 and 32 [-Werror=format-overflow=]
printf(ioc->name, "%s_cm%d", ioc->driver_name, ioc->id);
^~~~~~~~~
drivers/scsi/mpt3sas/mpt3sas_scsih.c:8884:21: note: directive argument in the range [0, 255]
drivers/scsi/mpt3sas/mpt3sas_scsih.c:8884:2: note: 'sprintf' output between 5 and 38 bytes into a destination of size 32
sprintf(ioc->name, "%s_cm%d", ioc->driver_name, ioc->id);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Making the first string shorter is sufficient to avoid the
warning here, as we know it can only contain either "mpt2sas"
or "mpt3sas".

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/scsi/mpt3sas/mpt3sas_base.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/mpt3sas/mpt3sas_base.h b/drivers/scsi/mpt3sas/mpt3sas_base.h
index 099ab4ca7edf..a77bb7dc12b1 100644
--- a/drivers/scsi/mpt3sas/mpt3sas_base.h
+++ b/drivers/scsi/mpt3sas/mpt3sas_base.h
@@ -970,7 +970,7 @@ struct MPT3SAS_ADAPTER {
u8 id;
int cpu_count;
char name[MPT_NAME_LENGTH];
- char driver_name[MPT_NAME_LENGTH];
+ char driver_name[MPT_NAME_LENGTH - 8];
char tmp_string[MPT_STRING_LENGTH];
struct pci_dev *pdev;
Mpi2SystemInterfaceRegs_t __iomem *chip;
--
2.9.0