x86-64: Fix the failure case in copy_user_handle_tail()
authorCQ Tang <cq.tang@intel.com>
Mon, 18 Mar 2013 15:02:21 +0000 (11:02 -0400)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Thu, 28 Mar 2013 19:12:26 +0000 (12:12 -0700)
commit56d833d3ed356e861ede0dd1c530ed5185d1215e
tree4326ea27fad104c1f2283cba42f9527c448a02cd
parent8d96fcec68c30196fca01a75a911835c7b89a50d
x86-64: Fix the failure case in copy_user_handle_tail()

commit 66db3feb486c01349f767b98ebb10b0c3d2d021b upstream.

The increment of "to" in copy_user_handle_tail() will have incremented
before a failure has been noted.  This causes us to skip a byte in the
failure case.

Only do the increment when assured there is no failure.

Signed-off-by: CQ Tang <cq.tang@intel.com>
Link: http://lkml.kernel.org/r/20130318150221.8439.993.stgit@phlsvslse11.ph.intel.com
Signed-off-by: Mike Marciniszyn <mike.marciniszyn@intel.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/lib/usercopy_64.c