On Wed, Mar 8, 2017 at 1:48 PM, Dave Young <dyoung@xxxxxxxxxx> wrote: > On 03/08/17 at 03:47pm, Baoquan He wrote: >> 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 <bhe@xxxxxxxxxx> >> --- >> 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 >> > > Acked-by: Dave Young <dyoung@xxxxxxxxxx> > Thanks Bao for this fix. This makes the KASLR code consistent with Address space markers hints in [1] [1] http://lxr.free-electrons.com/source/arch/x86/mm/dump_pagetables.c#L82 Reviewed-by: Bhupesh Sharma <bhsharma@xxxxxxxxxx> Regards, Bhupesh -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
