Software bugs

Design Bugs

• Don’t Repeat Yourself violation
• Bad API usage
• Using deprecated functions
• Incorrect variable manipulation
• Incorrect regular expression use
• Incorrect protocol implementation
• Unauthorized user access
• Conceptual Error
• Incorrect documentation
• Incorrect return value
• Incorrect database query
• Incorrect business rules

UI Bugs

• Missing/bad information
• Insufficient performance
• Inappropriate error message
• Expectation failure

Code Bugs

• Syntax error
• Off-by-one
• Division-by-zero
• Loss of arithmetic precision
• Injection attack
• Overflow
• Underflow
• Infinite loop
• Uninitialized variable
• Incorrect initialization of variable
• Resource leak
• Excessive recursion
• Null pointer dereference
• Race condition
• Doesn’t return memory when finished
• incorrect data type handling
• Incorrect file handling

Testing Errors

• Did not provide steps to reproduce
• Misunderstanding of documentation
• Failed to notice or report problem
• Failed to run automated tests first
• Failure to verify fixes

Time bugs

Wikipedia list of time bugs

TOPS-10

Has a clock for [1964-01-01 Wed] to [1975-01-04 Sat]. It was given another 3 bits to go to [2052-02-01 Thu], but this crept into other data structures in use causing weird bugs

NTP overflow

Unix 32-bit

2038

World Computer Corporation

2028

GPS epoch

Last was in 2019 - happens every 1024 weeks