linux-brain/arch/x86/include
Fan Yang df4988aa1c mm: Fix mremap not considering huge pmd devmap
commit 5bfea2d9b17f1034a68147a8b03b9789af5700f9 upstream.

The original code in mm/mremap.c checks huge pmd by:

		if (is_swap_pmd(*old_pmd) || pmd_trans_huge(*old_pmd)) {

However, a DAX mapped nvdimm is mapped as huge page (by default) but it
is not transparent huge page (_PAGE_PSE | PAGE_DEVMAP).  This commit
changes the condition to include the case.

This addresses CVE-2020-10757.

Fixes: 5c7fb56e5e ("mm, dax: dax-pmd vs thp-pmd vs hugetlbfs-pmd")
Cc: <stable@vger.kernel.org>
Reported-by: Fan Yang <Fan_Yang@sjtu.edu.cn>
Signed-off-by: Fan Yang <Fan_Yang@sjtu.edu.cn>
Tested-by: Fan Yang <Fan_Yang@sjtu.edu.cn>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-06-07 13:18:46 +02:00
..
asm mm: Fix mremap not considering huge pmd devmap 2020-06-07 13:18:46 +02:00
uapi/asm x86/syscalls: Revert "x86/syscalls: Make __X32_SYSCALL_BIT be unsigned long" 2020-06-03 08:21:29 +02:00