tree bc886181f598356f5b010c16235b9069633685b8
parent c4e8308c30b0139f89bac71f3c22c8d7413b8665
author David Daney <ddaney@avtrex.com> 1193551820 -0700
committer Ralf Baechle <ralf@linux-mips.org> 1193686536 +0000

[MIPS] Add len and addr validation for MAP_FIXED mappings.

Mmap with MAP_FIXED was not validating the addr and len parameters.  This
leads to the failure of GCC's gcc.c-torture/execute/loop-2[fg].c testcases
when using the o32 ABI on a 64 bit kernel.

These testcases try to mmap 65536 bytes at 0x7fff8000 and then access all
the memory.  In 2.6.18 and 2.6.23.1 (and likely other versions as well)
the kernel maps the requested memory, but since half of it is above
0x80000000 a SIGBUS is generated when it is accessed.

This patch moves the len validation above the MAP_FIXED processing so that
it is always validated.  It also adds validation to the addr parameter for
MAP_FIXED mappings.

Signed-off-by: David Daney  <ddaney@avtrex.com>
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>