From 33027c2bb53e33bdb7749d357da199cb54e8fb6f Mon Sep 17 00:00:00 2001 From: Arnd Bergmann Date: Fri, 14 Jul 2017 14:07:11 +0200 Subject: [PATCH] block: DAC960: shut up format-overflow warning gcc-7 points out that a large controller number would overflow the string length for the procfs name and the firmware version string: drivers/block/DAC960.c: In function 'DAC960_Probe': drivers/block/DAC960.c:6591:38: warning: 'sprintf' may write a terminating nul past the end of the destination [-Wformat-overflow=] drivers/block/DAC960.c: In function 'DAC960_V1_ReadControllerConfiguration': drivers/block/DAC960.c:1681:40: error: '%02d' directive writing between 2 and 3 bytes into a region of size between 2 and 5 [-Werror=format-overflow=] drivers/block/DAC960.c:1681:40: note: directive argument in the range [0, 255] drivers/block/DAC960.c:1681:3: note: 'sprintf' output between 10 and 14 bytes into a destination of size 12 Both of these seem appropriately sized, and using snprintf() instead of sprintf() improves this by ensuring that even incorrect data won't cause undefined behavior here. Signed-off-by: Arnd Bergmann Signed-off-by: Jens Axboe --- drivers/block/DAC960.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/drivers/block/DAC960.c b/drivers/block/DAC960.c index 245a879b036e..255591ab3716 100644 --- a/drivers/block/DAC960.c +++ b/drivers/block/DAC960.c @@ -1678,9 +1678,12 @@ static bool DAC960_V1_ReadControllerConfiguration(DAC960_Controller_T Enquiry2->FirmwareID.FirmwareType = '0'; Enquiry2->FirmwareID.TurnID = 0; } - sprintf(Controller->FirmwareVersion, "%d.%02d-%c-%02d", - Enquiry2->FirmwareID.MajorVersion, Enquiry2->FirmwareID.MinorVersion, - Enquiry2->FirmwareID.FirmwareType, Enquiry2->FirmwareID.TurnID); + snprintf(Controller->FirmwareVersion, sizeof(Controller->FirmwareVersion), + "%d.%02d-%c-%02d", + Enquiry2->FirmwareID.MajorVersion, + Enquiry2->FirmwareID.MinorVersion, + Enquiry2->FirmwareID.FirmwareType, + Enquiry2->FirmwareID.TurnID); if (!((Controller->FirmwareVersion[0] == '5' && strcmp(Controller->FirmwareVersion, "5.06") >= 0) || (Controller->FirmwareVersion[0] == '4' && @@ -6588,7 +6591,8 @@ static void DAC960_CreateProcEntries(DAC960_Controller_T *Controller) &dac960_proc_fops); } - sprintf(Controller->ControllerName, "c%d", Controller->ControllerNumber); + snprintf(Controller->ControllerName, sizeof(Controller->ControllerName), + "c%d", Controller->ControllerNumber); ControllerProcEntry = proc_mkdir(Controller->ControllerName, DAC960_ProcDirectoryEntry); proc_create_data("initial_status", 0, ControllerProcEntry, &dac960_initial_status_proc_fops, Controller);