|
Message-Id: <1486747005-15973-4-git-send-email-ard.biesheuvel@linaro.org> Date: Fri, 10 Feb 2017 17:16:44 +0000 From: Ard Biesheuvel <ard.biesheuvel@...aro.org> To: linux-arm-kernel@...ts.infradead.org, mark.rutland@....com, will.deacon@....com, catalin.marinas@....com, keescook@...omium.org, labbott@...oraproject.org, james.morse@....com Cc: kvmarm@...ts.cs.columbia.edu, marc.zyngier@....com, christoffer.dall@...aro.org, kernel-hardening@...ts.openwall.com, andre.przywara@....com, Ard Biesheuvel <ard.biesheuvel@...aro.org> Subject: [PATCH 3/4] arm64: mmu: map .text as read-only from the outset Now that alternatives patching code no longer relies on the primary mapping of .text being writable, we can remove the code that removes the writable permissions post-init time, and map it read-only from the outset. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@...aro.org> --- arch/arm64/mm/mmu.c | 5 +---- 1 file changed, 1 insertion(+), 4 deletions(-) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index f4b045d1cc53..5b0dbb9156ce 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -442,9 +442,6 @@ void mark_rodata_ro(void) { unsigned long section_size; - section_size = (unsigned long)_etext - (unsigned long)_text; - create_mapping_late(__pa_symbol(_text), (unsigned long)_text, - section_size, PAGE_KERNEL_ROX); /* * mark .rodata as read only. Use __init_begin rather than __end_rodata * to cover NOTES and EXCEPTION_TABLE. @@ -487,7 +484,7 @@ static void __init map_kernel(pgd_t *pgd) { static struct vm_struct vmlinux_text, vmlinux_rodata, vmlinux_init, vmlinux_data; - map_kernel_segment(pgd, _text, _etext, PAGE_KERNEL_EXEC, &vmlinux_text); + map_kernel_segment(pgd, _text, _etext, PAGE_KERNEL_ROX, &vmlinux_text); map_kernel_segment(pgd, __start_rodata, __init_begin, PAGE_KERNEL, &vmlinux_rodata); map_kernel_segment(pgd, __init_begin, __init_end, PAGE_KERNEL_EXEC, &vmlinux_init); -- 2.7.4
Powered by blists - more mailing lists
Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.