x86/ptrace: Use get_user() in the general register set writers

genregs_set() and genregs32_set() read the user buffer one word at a
time with __get_user(), calling putreg() for each.  The access_ok() that
makes this safe is in the generic copy_regset_from_user(), on the other
side of an indirect call through the regset.  Each of those accesses
enables and disables user access on its own, so the up-front check saves
nothing.  On x86, __get_user() is even more expensive than get_user():
it does an lfence, where get_user() checks the address with a couple of
plain instructions.

Use get_user(), so each read checks its own address.

This is part of getting rid of __get_user() and __put_user() entirely.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

0 files changed, 0 insertions, 0 deletions