Linux: ZStack Linux Gateway - Suspicious looking code

Jason Cole26

Tool/software: Linux

Around line 945 in zbSocCmd (z-stack-linux/Source/Projects/zstack/linux/sbl_tool/Source/zbSocCmd.c)

	if (finish_code != SBL_TARGET_STILL_WORKING)
	{
		zbSocFinishLoadingImage(finish_code);                     // <----------------------------------------------------------- !!!!!!!!

		if (finish_code == SBL_SUCCESS);
		{
			zbSocForceRun();
			finish_state = STATE_FINISHED_OK_WAIT;
			printf("Waiting for optional system version information. Press [ENTER] to stop waiting.\n");
			zbSocEnableTimeoutContinious(REPORTING_TIMER, 10000);
		}
		return;
	}

over 8 years ago

0 JasonB over 8 years ago

TI__Expert 8950 points

Hi,

What gateway release version do you have? I don't see this in my code.

0 Jason Cole26 over 8 years ago in reply to JasonB

Intellectual 710 points

It's in both version 2 and version 3 (Alpha) of the Linux-Zigbee-Gateway.

The older 32-bit compiler linked on the TI website doesn't report a warning.

The newer 64-bit compiler linked here, does:

https://eewiki.net/display/linuxonarm/BeagleBone#BeagleBone-ARMCrossCompiler:GCC

0 Jason Cole26 over 8 years ago in reply to Jason Cole26

Intellectual 710 points

Just to be clear, it is "if (finish_code == SBL_SUCCESS);" that is the offending line.

0 JasonB over 8 years ago in reply to Jason Cole26

TI__Expert 8950 points

Hi,

I'm not sure I fully understand your concerns surrounding this code and why you are saying it is "suspicious", can you please elaborate?

The logic seems fine, the value of finish_code is assigned earlier in this function, you can then enter the if() statement if finish_code != SBL_TARGET_STILL_WORKING, execute zbSocFinishLoadingImage() based on the current value of finish_code (which is not SBL_TARGET_STILL_WORKING), and then execute another if() statement if finish_code (which was assigned earlier) is SBL_SUCCESS.

Maybe it seems slightly confusing because zbSocFinishLoadingImage is not modifying the value of finish_code but this was intentional.

0 Jason Cole26 over 8 years ago in reply to JasonB

Intellectual 710 points

The logic of this piece of code is written to appear as though the block should only execute if finish_code is SBL_SUCCESS.

What will actually happen is that the block will *always* run due to the semicolon at the end of the if statement.

if (finish_code == SBL_SUCCESS);
{
zbSocForceRun();
finish_state = STATE_FINISHED_OK_WAIT;
printf("Waiting for optional system version information. Press [ENTER] to stop waiting.\n");
zbSocEnableTimeoutContinious(REPORTING_TIMER, 10000);
}

0 JasonB over 8 years ago in reply to Jason Cole26

TI__Expert 8950 points

Oh! You are totally right, I completely missed the semi colon right there.

Thanks for pointing this out, we will fix this in the next release.

Zigbee & Thread

Zigbee & Thread forum

Linux: ZStack Linux Gateway - Suspicious looking code