Re: mm: insure topdown mmap chooses addresses above security minimum

2013-09-27 Thread Timothy Pepper
On Wed 25 Sep at 19:44:36 +0200 mi...@kernel.org said: * Timothy Pepper timothy.c.pep...@linux.intel.com wrote: On Wed 25 Sep at 09:30:49 +0200 mi...@kernel.org said: info.flags = VM_UNMAPPED_AREA_TOPDOWN; info.length = len; - info.low_limit = PAGE_SIZE;

Re: mm: insure topdown mmap chooses addresses above security minimum

2013-09-25 Thread Ingo Molnar
* Timothy Pepper timothy.c.pep...@linux.intel.com wrote: A security check is performed on mmap addresses in security/security.c:security_mmap_addr(). It uses mmap_min_addr to insure mmaps don't get addresses lower than a user configurable guard value (/proc/sys/vm/mmap_min_addr). The arch

Re: mm: insure topdown mmap chooses addresses above security minimum

2013-09-25 Thread Timothy Pepper
On Wed 25 Sep at 09:30:49 +0200 mi...@kernel.org said: info.flags = VM_UNMAPPED_AREA_TOPDOWN; info.length = len; - info.low_limit = PAGE_SIZE; + info.low_limit = max(PAGE_SIZE, PAGE_ALIGN(mmap_min_addr)); info.high_limit = mm-mmap_base; info.align_mask = filp ?

Re: mm: insure topdown mmap chooses addresses above security minimum

2013-09-25 Thread Ingo Molnar
* Timothy Pepper timothy.c.pep...@linux.intel.com wrote: On Wed 25 Sep at 09:30:49 +0200 mi...@kernel.org said: info.flags = VM_UNMAPPED_AREA_TOPDOWN; info.length = len; - info.low_limit = PAGE_SIZE; + info.low_limit = max(PAGE_SIZE, PAGE_ALIGN(mmap_min_addr));

Re: mm: insure topdown mmap chooses addresses above security minimum

2013-09-24 Thread Russell King - ARM Linux
On Tue, Sep 24, 2013 at 02:23:31PM -0700, Timothy Pepper wrote: diff --git a/arch/arm/mm/mmap.c b/arch/arm/mm/mmap.c index 0c63562..0e7355d 100644 --- a/arch/arm/mm/mmap.c +++ b/arch/arm/mm/mmap.c @@ -9,6 +9,7 @@ #include linux/io.h #include linux/personality.h #include linux/random.h