GETCPU(2) says:
int getcpu(unsigned *cpu, unsigned *node, struct getcpu_cache *tcache);
...
When either cpu or node is NULL nothing is written to the respective pointer.
But the fast system call path had no checks for NULL, and would
thus return -EFAULT if either (or both) of these were NULL.
Reported-by: Mike Frysinger <vapier@gentoo.org>
Tested-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Tony Luck <tony.luck@intel.com>