[PATCH] hugetlb: check for brk() entering a hugepage region
commitcb07c9a1864a8eac9f3123e428100d5b2a16e65a
authorDavid Gibson <david@gibson.dropbear.id.au>
Tue, 14 Nov 2006 10:03:38 +0000 (14 02:03 -0800)
committerLinus Torvalds <torvalds@woody.osdl.org>
Tue, 14 Nov 2006 17:09:27 +0000 (14 09:09 -0800)
treefadc568154bbe3c1466081b718e9638438c82c46
parent68589bc353037f233fe510ad9ff432338c95db66
[PATCH] hugetlb: check for brk() entering a hugepage region

Unlike mmap(), the codepath for brk() creates a vma without first checking
that it doesn't touch a region exclusively reserved for hugepages.  On
powerpc, this can allow it to create a normal page vma in a hugepage
region, causing oopses and other badness.

Add a test to prevent this.  With this patch, brk() will simply fail if it
attempts to move the break into a hugepage reserved region.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Cc: Adam Litke <agl@us.ibm.com>
Cc: Hugh Dickins <hugh@veritas.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
mm/mmap.c