[PATCH 1/2] powerpc: ptrace CHECK_FULL_REGS

Roland McGrath roland at redhat.com
Tue Sep 25 10:59:44 EST 2007

> Yup, I think I ditched most of them.. for some reason I decided it
> couldn't happen, but maybe I'm wrong ?

Well, it's a BUG_ON.  It's supposed to be for something that "can't happen".
That's why it's a sanity check, not a wild assertion. ;-)

The 2/2 patch is an example of a bug that CHECK_FULL_REGS catches.
In the status quo, using PTRACE_PEEKUSR in a bug case crashes while using
PTRACE_GETREGS in the same place might get bogus data.  (In the actual bug
thus found, the data is not bogus and only the bit that FULL_REGS checks is.)


More information about the Linuxppc-dev mailing list