From 0b2aa5b80bbf4d0fb5daa1fb83ff637daa12d552 Mon Sep 17 00:00:00 2001 From: Laura Abbott Date: Thu, 12 Nov 2015 12:21:10 -0800 Subject: [PATCH] arm64: Fix R/O permissions in mark_rodata_ro The permissions in mark_rodata_ro trigger a build error with STRICT_MM_TYPECHECKS. Fix this by introducing PAGE_KERNEL_ROX for the same reasons as PAGE_KERNEL_RO. From Ard: "PAGE_KERNEL_EXEC has PTE_WRITE set as well, making the range writeable under the ARMv8.1 DBM feature, that manages the dirty bit in hardware (writing to a page with the PTE_RDONLY and PTE_WRITE bits both set will clear the PTE_RDONLY bit in that case)" Signed-off-by: Laura Abbott Acked-by: Ard Biesheuvel Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/pgtable.h | 1 + arch/arm64/mm/mmu.c | 2 +- 2 files changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 9819a9426b69..7e074f93f383 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -81,6 +81,7 @@ extern void __pgd_error(const char *file, int line, unsigned long val); #define PAGE_KERNEL __pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_WRITE) #define PAGE_KERNEL_RO __pgprot(_PAGE_DEFAULT | PTE_PXN | PTE_UXN | PTE_DIRTY | PTE_RDONLY) +#define PAGE_KERNEL_ROX __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_RDONLY) #define PAGE_KERNEL_EXEC __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE) #define PAGE_KERNEL_EXEC_CONT __pgprot(_PAGE_DEFAULT | PTE_UXN | PTE_DIRTY | PTE_WRITE | PTE_CONT) diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c index 32ddd893da9a..abb66f84d4ac 100644 --- a/arch/arm64/mm/mmu.c +++ b/arch/arm64/mm/mmu.c @@ -475,7 +475,7 @@ void mark_rodata_ro(void) { create_mapping_late(__pa(_stext), (unsigned long)_stext, (unsigned long)_etext - (unsigned long)_stext, - PAGE_KERNEL_EXEC | PTE_RDONLY); + PAGE_KERNEL_ROX); } #endif -- 2.20.1