diff options
| author | Will Deacon <will.deacon@arm.com> | 2012-09-01 05:22:12 +0100 |
|---|---|---|
| committer | Will Deacon <will.deacon@arm.com> | 2012-11-09 14:13:20 +0000 |
| commit | 26ffd0d43b186b0d5186354da8714a1c2d360df0 (patch) | |
| tree | 405c83d298530b65bb64630da52cfb368927691a /drivers | |
| parent | dbf62d50067e55a782583fe53c3d2a3d98b1f6f3 (diff) | |
ARM: mm: introduce present, faulting entries for PAGE_NONE
PROT_NONE mappings apply the page protection attributes defined by _P000
which translate to PAGE_NONE for ARM. These attributes specify an XN,
RDONLY pte that is inaccessible to userspace. However, on kernels
configured without support for domains, such a pte *is* accessible to
the kernel and can be read via get_user, allowing tasks to read
PROT_NONE pages via syscalls such as read/write over a pipe.
This patch introduces a new software pte flag, L_PTE_NONE, that is set
to identify faulting, present entries.
Signed-off-by: Will Deacon <will.deacon@arm.com>
Diffstat (limited to 'drivers')
0 files changed, 0 insertions, 0 deletions