From mboxrd@z Thu Jan 1 00:00:00 1970 From: Baoquan He Subject: [PATCH 2/2] x86/mm/KASLR: Correct the upper boundary of KALSR mm regions if adjacent to EFI Date: Wed, 8 Mar 2017 15:47:38 +0800 Message-ID: <1488959258-4731-2-git-send-email-bhe@redhat.com> References: <1488959258-4731-1-git-send-email-bhe@redhat.com> Return-path: In-Reply-To: <1488959258-4731-1-git-send-email-bhe-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org> Sender: linux-efi-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org Cc: linux-efi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, thgarnie-hpIqsD4AKlfQT0dZR+AlfA@public.gmane.org, keescook-F7+t8E8rja9g9hUCZPvPmw@public.gmane.org, tglx-hfZtesqFncYOwBW4kG4KsQ@public.gmane.org, mingo-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, hpa-YMNOUZJC4hwAvxtiuMwx3w@public.gmane.org, x86-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, akpm-de/tnXTf+JLsfHDXvbKv3WD2FQJk+8+b@public.gmane.org, dyoung-H+wXaHxf7aLQT0dZR+AlfA@public.gmane.org, Baoquan He List-Id: linux-efi@vger.kernel.org EFI allocates runtime services regions top-down, starting from EFI_VA_START to EFI_VA_END. So EFI_VA_START is bigger than EFI_VA_END and is the end of EFI region. The upper boundary of memory regions randomized by KASLR should be EFI_VA_END if it's adjacent to EFI region, but not EFI_VA_START. Correct it in this patch. Signed-off-by: Baoquan He --- arch/x86/mm/kaslr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/arch/x86/mm/kaslr.c b/arch/x86/mm/kaslr.c index 887e571..aed2064 100644 --- a/arch/x86/mm/kaslr.c +++ b/arch/x86/mm/kaslr.c @@ -48,7 +48,7 @@ static const unsigned long vaddr_start = __PAGE_OFFSET_BASE; #if defined(CONFIG_X86_ESPFIX64) static const unsigned long vaddr_end = ESPFIX_BASE_ADDR; #elif defined(CONFIG_EFI) -static const unsigned long vaddr_end = EFI_VA_START; +static const unsigned long vaddr_end = EFI_VA_END; #else static const unsigned long vaddr_end = __START_KERNEL_map; #endif @@ -105,7 +105,7 @@ void __init kernel_randomize_memory(void) */ BUILD_BUG_ON(vaddr_start >= vaddr_end); BUILD_BUG_ON(IS_ENABLED(CONFIG_X86_ESPFIX64) && - vaddr_end >= EFI_VA_START); + vaddr_end >= EFI_VA_END); BUILD_BUG_ON((IS_ENABLED(CONFIG_X86_ESPFIX64) || IS_ENABLED(CONFIG_EFI)) && vaddr_end >= __START_KERNEL_map); -- 2.5.5