| Message ID | 20170719125310.2487451-9-arnd@arndb.de |
|---|---|
| State | Accepted |
| Commit | 0bc73048d7baecf94117d1a948853a627e6ba5c8 |
| Headers | show |
| Series | x86: randconfig warning fixes | expand |
diff --git a/arch/x86/platform/intel-mid/device_libs/platform_max7315.c b/arch/x86/platform/intel-mid/device_libs/platform_max7315.c index 6e075afa7877..58337b2bc682 100644 --- a/arch/x86/platform/intel-mid/device_libs/platform_max7315.c +++ b/arch/x86/platform/intel-mid/device_libs/platform_max7315.c @@ -38,8 +38,10 @@ static void __init *max7315_platform_data(void *info) */ strcpy(i2c_info->type, "max7315"); if (nr++) { - sprintf(base_pin_name, "max7315_%d_base", nr); - sprintf(intr_pin_name, "max7315_%d_int", nr); + snprintf(base_pin_name, sizeof(base_pin_name), + "max7315_%d_base", nr); + snprintf(intr_pin_name, sizeof(intr_pin_name), + "max7315_%d_int", nr); } else { strcpy(base_pin_name, "max7315_base"); strcpy(intr_pin_name, "max7315_int");
We have space for exactly three characters for the index in "max7315_%d_base", but as gcc points out having more would cause an string overflow: arch/x86/platform/intel-mid/device_libs/platform_max7315.c: In function 'max7315_platform_data': arch/x86/platform/intel-mid/device_libs/platform_max7315.c:41:26: error: '%d' directive writing between 1 and 11 bytes into a region of size 9 [-Werror=format-overflow=] sprintf(base_pin_name, "max7315_%d_base", nr); ^~~~~~~~~~~~~~~~~ arch/x86/platform/intel-mid/device_libs/platform_max7315.c:41:26: note: directive argument in the range [-2147483647, 2147483647] arch/x86/platform/intel-mid/device_libs/platform_max7315.c:41:3: note: 'sprintf' output between 15 and 25 bytes into a destination of size 17 sprintf(base_pin_name, "max7315_%d_base", nr); This makes it use an snprintf() to truncate the string if that happened rather than overflowing the stack. In practice, this is safe, because there won't be a large number of max7315 devices in the systems, and both the format and the length are defined by the firmware interface. Signed-off-by: Arnd Bergmann <arnd@arndb.de> --- Originally submitted on July 14, this is the same patch with slightly improved changelog. --- arch/x86/platform/intel-mid/device_libs/platform_max7315.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) -- 2.9.0