tree e978297e32ec373ba6b1d1612038a882f49837ae
parent df17d398eca83d6de2f42cade70d317bebeec071
author DRC <information@libjpeg-turbo.org> 1617731463 -0500
committer DRC <information@libjpeg-turbo.org> 1617743549 -0500

tjLoadImage: Fix issues w/loading 16-bit PPMs/PGMs

- The PPM reader now throws an error rather than segfaulting (due to a
  buffer overrun) if an application attempts to load a 16-bit PPM file
  into a grayscale uncompressed image buffer.  No known applications
  allowed that (not even the test applications in libjpeg-turbo),
  because that mode of operation was never expected to work and did not
  work under any circumstances.  (In fact, it was necessary to modify
  TJBench in order to reproduce the issue outside of a fuzzing
  environment.)  This was purely a matter of making the library bow out
  gracefully rather than crash if an application tries to do something
  really stupid.

- The PPM reader now throws an error rather than generating incorrect
  pixels if an application attempts to load a 16-bit PGM file into an
  RGB uncompressed image buffer.

- The PPM reader now correctly loads 16-bit PPM files into extended
  RGB uncompressed image buffers.  (Previously it generated incorrect
  pixels unless the input colorspace was JCS_RGB or JCS_EXT_RGB.)

The only way that users could have potentially encountered these issues
was through the tjLoadImage() function.  cjpeg and TJBench were
unaffected.