Re: FreeCOM example bug: command.c / executes everything

X-Comment-To: Eric Auer

Hi!

13-=EE=CF=D1-2002 21:06 [email protected] (Eric Auer) wrote to fd-dev@top=
ica.com:

EA> I just noticed a very old bug still to exist.
EA> In command.c of the most recent FreeCOM:
EA>   if (stricmp(strrchr(fullname, '.'), ".bat") =3D=3D 0)
EA>   {
EA>     dprintf(("[BATCH: %s %s]\n", fullname, rest));
EA>     batch(fullname, first, rest);
EA>   }
EA>   else
EA>     /* exec the program */
EA> ... no tests at all if it is called .com or .exe ! ...
EA>     result =3D exec(fullname, rest, 0);
EA> ...
EA> So if you accidentally tab-complete on program.txt and then hit enter,
EA> a nice juicy crash will hit you back.

1. MS command.com runs only files with extension .bat, .com and .exe.
2. You may verify that file is real .EXE by  checking sugnature, but you
   can't distinguish files with forma of .COM, .BAT or any other format.
3. Distinguishing between .COM and .EXE _formats_ (not extensions!)
   performed by kernel, shell should only filter out files with .BAT (and
   .BTM for 4DOS/NDOS) extension.