So could we use this inspeakup to write and read from a serial device -- thus circumventing most of our serial problems? Chris Brannon <chris at the-brannons.com> wrote: > Don Raikes <don.raikes at oracle.com> writes: > > My solution: > > > > Allocate a new larger buffer inside of the userspace and copy_to_user > > into the new buffer and then when I pass control to the "real" > > sys_write function point it to the new buffer. > > But the problem is how do I allocate this new buffer? > > There's no easy way to do this. You can't just pass your kernel > buffer to the system call you are intercepting, since the intercepted > call expects a user-space buffer. > Have a look at this link for some inspiration: > http://web.cs.wpi.edu/~cs4513/b05/proj1note2.txt > > Also be careful about the return value of the real sys_write system > call. If you're passing it a buffer larger than the n bytes passed in > from userspace, its return value can be greater than n. Don't just use > it unmodified as the return value for your function. > > -- Chris > _______________________________________________ > Speakup mailing list > Speakup at linux-speakup.org > http://linux-speakup.org/cgi-bin/mailman/listinfo/speakup -- Your life is like a penny. You're going to lose it. The question is: How do you spend it? John Covici covici at ccs.covici.com
