x86/vdso: Set VM_MAYREAD for the vvar vma

The VVAR area can, obviously, be read; that is kind of the point.

AFAIK this has no effect whatsoever unless x86 suddenly turns into a
nommu architecture.  Nonetheless, not setting it is suspicious.

Reported-by: Nathan Lynch <Nathan_Lynch@mentor.com>
Signed-off-by: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/e4c8bf4bc2725bda22c4a4b7d0c82adcd8f8d9b8.1406330779.git.luto@amacapital.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
This commit is contained in:
Andy Lutomirski 2014-07-25 16:27:01 -07:00 committed by H. Peter Anvin
parent da861e18ec
commit ac379835e8

View file

@ -138,7 +138,7 @@ static int map_vdso(const struct vdso_image *image, bool calculate_addr)
vma = _install_special_mapping(mm,
addr,
-image->sym_vvar_start,
VM_READ,
VM_READ|VM_MAYREAD,
&vvar_mapping);
if (IS_ERR(vma)) {