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Possible buffer overrun in ssd.c? #11

tmmagee opened this Issue · 5 comments

3 participants


In ssd.c the scannerInput array is defined as follows:

 char scannerInput[12];

But later in the code when the scanner input is read:

  for (i = 0; i < 17; i++) {
       scannerInput[i] = serialBuffer[i+4];

Is this buffer overrun intentional? I have seen this code in multiple is4c forks on github and it has not been corrected. I changed the size of scannerInput to 17 in my own code to correct the issue, and the daemon still appears to run fine. Is there something I am missing?


That's a good find. I've ran through this code numerous times and never noticed it. I wonder if anyone else has any thoughts on this.


I tried that fix and it did not work for me. Items did not scan correctly. I did not debug the issue, but I can only assume that by making the change you suggest the scanner was no longer scanning in the entire barcode.

Changing the size of the scannerInput to 17, however, did work just fine.

One note: the store I am working for (Mariposa Food Co-op) reads the check digit in UPC barcodes, so perhaps that was my problem for the fix you have just suggested.


Your fix worked for us, Bottlecap. Thanks for the help.

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