Commit eb099e5b authored Jun 07, 2015 by Dave Hansen Committed by Ingo Molnar Jun 09, 2015

x86/mpx: Restrict the mmap() size check to bounds tables

The comment and code here are confusing.  We do not currently
allocate the bounds directory in the kernel.

Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Dave Hansen <dave@sr71.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20150607183702.222CEC2A@viggo.jf.intel.com

Signed-off-by: Ingo Molnar <mingo@kernel.org>

parent 3c1d3230

arch/x86/mm/mpx.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -46,8 +46,8 @@ static unsigned long mpx_mmap(unsigned long len)
		vm_flags_t vm_flags;
		struct vm_area_struct *vma;

		/* Only bounds table and bounds directory can be allocated here */
		if (len != MPX_BD_SIZE_BYTES && len != MPX_BT_SIZE_BYTES)
		/* Only bounds table can be allocated here */
		if (len != MPX_BT_SIZE_BYTES)
		return -EINVAL;

		down_write(&mm->mmap_sem);