From: Benjamin Herrenschmidt Date: Wed, 8 Aug 2007 05:44:15 +0000 (+1000) Subject: [POWERPC] Fix size check for hugetlbfs X-Git-Tag: v2.6.23-rc3~9^2 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=d1f5a77f2c9db5b8a565eabdf8b534b02e32cc44;p=linux-2.6 [POWERPC] Fix size check for hugetlbfs My "slices" address space management code that was added in the 2.6.22 implementation of get_unmapped_area() doesn't properly check that the size is a multiple of the requested page size. This allows userland to create VMAs that aren't a multiple of the huge page size with hugetlbfs (since hugetlbfs entirely relies on get_unmapped_area() to do that checking) which leads to a kernel BUG() when such areas are torn down. Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Paul Mackerras --- diff --git a/arch/powerpc/mm/slice.c b/arch/powerpc/mm/slice.c index f833dba2a0..d5fd3909d1 100644 --- a/arch/powerpc/mm/slice.c +++ b/arch/powerpc/mm/slice.c @@ -405,6 +405,8 @@ unsigned long slice_get_unmapped_area(unsigned long addr, unsigned long len, if (len > mm->task_size) return -ENOMEM; + if (len & ((1ul << pshift) - 1)) + return -EINVAL; if (fixed && (addr & ((1ul << pshift) - 1))) return -EINVAL; if (fixed && addr > (mm->task_size - len))