[PATCH 13/22] liquidio: fix possible eeprom format string overflow

From: Arnd Bergmann
Date: Fri Jul 14 2017 - 08:12:28 EST


gcc reports that the temporary buffer for computing the
string length may be too small here:

drivers/net/ethernet/cavium/liquidio/lio_ethtool.c: In function 'lio_get_eeprom_len':
/drivers/net/ethernet/cavium/liquidio/lio_ethtool.c:345:21: error: 'sprintf' may write a terminating nul past the end of the destination [-Werror=format-overflow=]
len = sprintf(buf, "boardname:%s serialnum:%s maj:%lld min:%lld\n",
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/cavium/liquidio/lio_ethtool.c:345:6: note: 'sprintf' output between 35 and 167 bytes into a destination of size 128
len = sprintf(buf, "boardname:%s serialnum:%s maj:%lld min:%lld\n",

This extends it to 192 bytes, which is certainly enough. As far
as I could tell, there are no other constraints that require a specific
maximum size.

Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
drivers/net/ethernet/cavium/liquidio/lio_ethtool.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/cavium/liquidio/lio_ethtool.c b/drivers/net/ethernet/cavium/liquidio/lio_ethtool.c
index 28ecda3d3404..ebd353bc78ff 100644
--- a/drivers/net/ethernet/cavium/liquidio/lio_ethtool.c
+++ b/drivers/net/ethernet/cavium/liquidio/lio_ethtool.c
@@ -335,7 +335,7 @@ lio_ethtool_get_channels(struct net_device *dev,

static int lio_get_eeprom_len(struct net_device *netdev)
{
- u8 buf[128];
+ u8 buf[192];
struct lio *lio = GET_LIO(netdev);
struct octeon_device *oct_dev = lio->oct_dev;
struct octeon_board_info *board_info;
--
2.9.0