Single-bit errors are automatically corrected during read thus such error does not cause any program flow interruption. However this error stays physically present in flash memory, flash controller does not automatically re-flash memory, this does not happen.
Single bit error may be injected in flash memory the same way I have described here, section 6.2:
http://www.nxp.com/files/microcontrollers/doc/app_note/AN5200.pdf
Only it is needed to choose different pattern causing single bit error, for instance following:
- Write the original data A = 0xFFFFFFFF00000000 to a flash memory location.
- Over program data A to data B = 0xFFFFFFFF00000001 to the same flash memory location.