Here is another fix for a sparse-detected bug: turns out
ptrace_getregs() and ptrace_putregs() did unchecked user-memory
accesses!  These were tricky to see, so it's not surprising that they
went unnoticed so far.  Fortunately, sparse can detect these
trivially.  Patch below should fix the problem, but it's completely
untested (I don't have any testcases for getregs/putregs).

These were found by sparse.

Signed-off-by: davidm@hpl.hp.com
Signed-off-by: Tony Luck <tony.luck@intel.com>