From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753732AbcLFXwV (ORCPT ); Tue, 6 Dec 2016 18:52:21 -0500 Received: from mail-qt0-f170.google.com ([209.85.216.170]:32920 "EHLO mail-qt0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753341AbcLFXvk (ORCPT ); Tue, 6 Dec 2016 18:51:40 -0500 From: Laura Abbott To: Mark Rutland , Ard Biesheuvel , Will Deacon , Catalin Marinas Cc: Laura Abbott , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , x86@kernel.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Andrew Morton , Marek Szyprowski , Joonsoo Kim , linux-arm-kernel@lists.infradead.org Subject: [PATCHv5 11/11] arm64: Add support for CONFIG_DEBUG_VIRTUAL Date: Tue, 6 Dec 2016 15:50:57 -0800 Message-Id: <1481068257-6367-12-git-send-email-labbott@redhat.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1481068257-6367-1-git-send-email-labbott@redhat.com> References: <1481068257-6367-1-git-send-email-labbott@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org x86 has an option CONFIG_DEBUG_VIRTUAL to do additional checks on virt_to_phys calls. The goal is to catch users who are calling virt_to_phys on non-linear addresses immediately. This inclues callers using virt_to_phys on image addresses instead of __pa_symbol. As features such as CONFIG_VMAP_STACK get enabled for arm64, this becomes increasingly important. Add checks to catch bad virt_to_phys usage. Reviewed-by: Mark Rutland Tested-by: Mark Rutland Signed-off-by: Laura Abbott --- v5: Tweak warning output slightly, acks --- arch/arm64/Kconfig | 1 + arch/arm64/include/asm/memory.h | 31 ++++++++++++++++++++++++++++--- arch/arm64/mm/Makefile | 2 ++ arch/arm64/mm/physaddr.c | 30 ++++++++++++++++++++++++++++++ 4 files changed, 61 insertions(+), 3 deletions(-) create mode 100644 arch/arm64/mm/physaddr.c diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 969ef88..83b95bc 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -6,6 +6,7 @@ config ARM64 select ACPI_MCFG if ACPI select ACPI_SPCR_TABLE if ACPI select ARCH_CLOCKSOURCE_DATA + select ARCH_HAS_DEBUG_VIRTUAL select ARCH_HAS_DEVMEM_IS_ALLOWED select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI select ARCH_HAS_ELF_RANDOMIZE diff --git a/arch/arm64/include/asm/memory.h b/arch/arm64/include/asm/memory.h index 041bce28..a405665 100644 --- a/arch/arm64/include/asm/memory.h +++ b/arch/arm64/include/asm/memory.h @@ -167,10 +167,33 @@ extern u64 kimage_voffset; * private definitions which should NOT be used outside memory.h * files. Use virt_to_phys/phys_to_virt/__pa/__va instead. */ -#define __virt_to_phys(x) ({ \ + + +/* + * The linear kernel range starts in the middle of the virtual adddress + * space. Testing the top bit for the start of the region is a + * sufficient check. + */ +#define __is_lm_address(addr) (!!((addr) & BIT(VA_BITS - 1))) + +#define __lm_to_phys(addr) (((addr) & ~PAGE_OFFSET) + PHYS_OFFSET) +#define __kimg_to_phys(addr) ((addr) - kimage_voffset) + +#define __virt_to_phys_nodebug(x) ({ \ phys_addr_t __x = (phys_addr_t)(x); \ - __x & BIT(VA_BITS - 1) ? (__x & ~PAGE_OFFSET) + PHYS_OFFSET : \ - (__x - kimage_voffset); }) + __is_lm_address(__x) ? __lm_to_phys(__x) : \ + __kimg_to_phys(__x); \ +}) + +#define __pa_symbol_nodebug(x) __kimg_to_phys((phys_addr_t)(x)) + +#ifdef CONFIG_DEBUG_VIRTUAL +extern phys_addr_t __virt_to_phys(unsigned long x); +extern phys_addr_t __phys_addr_symbol(unsigned long x); +#else +#define __virt_to_phys(x) __virt_to_phys_nodebug(x) +#define __phys_addr_symbol(x) __pa_symbol_nodebug(x) +#endif #define __phys_to_virt(x) ((unsigned long)((x) - PHYS_OFFSET) | PAGE_OFFSET) #define __phys_to_kimg(x) ((unsigned long)((x) + kimage_voffset)) @@ -202,6 +225,8 @@ static inline void *phys_to_virt(phys_addr_t x) * Drivers should NOT use these either. */ #define __pa(x) __virt_to_phys((unsigned long)(x)) +#define __pa_symbol(x) __phys_addr_symbol(RELOC_HIDE((unsigned long)(x), 0)) +#define __pa_nodebug(x) __virt_to_phys_nodebug((unsigned long)(x)) #define __va(x) ((void *)__phys_to_virt((phys_addr_t)(x))) #define pfn_to_kaddr(pfn) __va((pfn) << PAGE_SHIFT) #define virt_to_pfn(x) __phys_to_pfn(__virt_to_phys((unsigned long)(x))) diff --git a/arch/arm64/mm/Makefile b/arch/arm64/mm/Makefile index 54bb209..38d3811 100644 --- a/arch/arm64/mm/Makefile +++ b/arch/arm64/mm/Makefile @@ -5,6 +5,8 @@ obj-y := dma-mapping.o extable.o fault.o init.o \ obj-$(CONFIG_HUGETLB_PAGE) += hugetlbpage.o obj-$(CONFIG_ARM64_PTDUMP) += dump.o obj-$(CONFIG_NUMA) += numa.o +obj-$(CONFIG_DEBUG_VIRTUAL) += physaddr.o +KASAN_SANITIZE_physaddr.o += n obj-$(CONFIG_KASAN) += kasan_init.o KASAN_SANITIZE_kasan_init.o := n diff --git a/arch/arm64/mm/physaddr.c b/arch/arm64/mm/physaddr.c new file mode 100644 index 0000000..91371da --- /dev/null +++ b/arch/arm64/mm/physaddr.c @@ -0,0 +1,30 @@ +#include +#include +#include +#include +#include + +#include + +phys_addr_t __virt_to_phys(unsigned long x) +{ + WARN(!__is_lm_address(x), + "virt_to_phys used for non-linear address: %pK (%pS)\n", + (void *)x, + (void *)x); + + return __virt_to_phys_nodebug(x); +} +EXPORT_SYMBOL(__virt_to_phys); + +phys_addr_t __phys_addr_symbol(unsigned long x) +{ + /* + * This is bounds checking against the kernel image only. + * __pa_symbol should only be used on kernel symbol addresses. + */ + VIRTUAL_BUG_ON(x < (unsigned long) KERNEL_START || + x > (unsigned long) KERNEL_END); + return __pa_symbol_nodebug(x); +} +EXPORT_SYMBOL(__phys_addr_symbol); -- 2.7.4