We get a warning for the port_name string that might be longer than six characters if we had more than 10 ports: drivers/net/ethernet/sun/niu.c: In function 'niu_put_parent': drivers/net/ethernet/sun/niu.c:9563:21: error: '%d' directive writing between 1 and 3 bytes into a region of size 2 [-Werror=format-overflow=] sprintf(port_name, "port%d", port); ^~~~~~~~ drivers/net/ethernet/sun/niu.c:9563:21: note: directive argument in the range [0, 255] drivers/net/ethernet/sun/niu.c:9563:2: note: 'sprintf' output between 6 and 8 bytes into a destination of size 6 sprintf(port_name, "port%d", port); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/net/ethernet/sun/niu.c: In function 'niu_pci_init_one': drivers/net/ethernet/sun/niu.c:9538:22: error: '%d' directive writing between 1 and 3 bytes into a region of size 2 [-Werror=format-overflow=] sprintf(port_name, "port%d", port); ^~~~~~~~ drivers/net/ethernet/sun/niu.c:9538:22: note: directive argument in the range [0, 255] drivers/net/ethernet/sun/niu.c:9538:3: note: 'sprintf' output between 6 and 8 bytes into a destination of size 6 While we know that the port number is small, there is no harm in making the format string two bytes longer to avoid the warning. Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx> --- drivers/net/ethernet/sun/niu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c index 46cb7f8955a2..4bb04aaf9650 100644 --- a/drivers/net/ethernet/sun/niu.c +++ b/drivers/net/ethernet/sun/niu.c @@ -9532,7 +9532,7 @@ static struct niu_parent *niu_get_parent(struct niu *np, p = niu_new_parent(np, id, ptype); if (p) { - char port_name[6]; + char port_name[8]; int err; sprintf(port_name, "port%d", port); @@ -9553,7 +9553,7 @@ static void niu_put_parent(struct niu *np) { struct niu_parent *p = np->parent; u8 port = np->port; - char port_name[6]; + char port_name[8]; BUG_ON(!p || p->ports[port] != np); -- 2.9.0