From f67af6d5803b6a015e30cb490a94f9547cb0437c Mon Sep 17 00:00:00 2001 From: Jan Beulich Date: Wed, 14 Aug 2013 11:20:26 +0200 Subject: [PATCH] x86/MTRR: fix range check in mtrr_add_page() Extracted from Yinghai Lu's Linux commit d5c78673 ("x86: Fix /proc/mtrr with base/size more than 44bits"). Signed-off-by: Jan Beulich Reviewed-by: Andrew Cooper Acked-by: Keir Fraser --- xen/arch/x86/cpu/mtrr/main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/xen/arch/x86/cpu/mtrr/main.c b/xen/arch/x86/cpu/mtrr/main.c index a201d72b6d..f7fc0a6e4b 100644 --- a/xen/arch/x86/cpu/mtrr/main.c +++ b/xen/arch/x86/cpu/mtrr/main.c @@ -340,7 +340,7 @@ int mtrr_add_page(unsigned long base, unsigned long size, return -EINVAL; } - if (base & size_or_mask || size & size_or_mask) { + if ((base | (base + size - 1)) >> (paddr_bits - PAGE_SHIFT)) { printk(KERN_WARNING "mtrr: base or size exceeds the MTRR width\n"); return -EINVAL; } -- 2.39.5