Re: [PATCH 17/22] platform/x86: alienware-wmi: fix format string overflow warning
From: Andy Shevchenko <hidden>
Date: 2017-07-14 19:18:29
Also in:
linux-scsi, lkml, platform-driver-x86
On Fri, Jul 14, 2017 at 3:07 PM, Arnd Bergmann [off-list ref] wrote:
gcc points out a possible format string overflow for a large value of 'zone':
drivers/platform/x86/alienware-wmi.c: In function 'alienware_wmi_init':
drivers/platform/x86/alienware-wmi.c:461:24: error: '%02X' directive writing between 2 and 8 bytes into a region of size 6 [-Werror=format-overflow=]
sprintf(buffer, "zone%02X", i);
^~~~
drivers/platform/x86/alienware-wmi.c:461:19: note: directive argument in the range [0, 2147483646]
sprintf(buffer, "zone%02X", i);
^~~~~~~~~~
drivers/platform/x86/alienware-wmi.c:461:3: note: 'sprintf' output between 7 and 13 bytes into a destination of size 10
While the zone should never be that large, it's easy to make the
buffer a few bytes longer so gcc can prove this to be safe.Please, be a bit smarter on such fixes. Here we need to convert int i; to u8 i; I will take it after addressing above. P.S. You may do this change across the file.
quoted hunk ↗ jump to hunk
Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- drivers/platform/x86/alienware-wmi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)diff --git a/drivers/platform/x86/alienware-wmi.c b/drivers/platform/x86/alienware-wmi.c index 0831b428c217..acc01242da82 100644 --- a/drivers/platform/x86/alienware-wmi.c +++ b/drivers/platform/x86/alienware-wmi.c@@ -421,7 +421,7 @@ static DEVICE_ATTR(lighting_control_state, 0644, show_control_state, static int alienware_zone_init(struct platform_device *dev) { int i; - char buffer[10]; + char buffer[13]; char *name; if (interface == WMAX) { --2.9.0
-- With Best Regards, Andy Shevchenko