From 6e2edd6371a497a6350bb735534c9bda2a31f43d Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Thu, 3 Mar 2022 18:00:44 +0000 Subject: arm64: Ensure execute-only permissions are not allowed without EPAN Commit 18107f8a2df6 ("arm64: Support execute-only permissions with Enhanced PAN") re-introduced execute-only permissions when EPAN is available. When EPAN is not available, arch_filter_pgprot() is supposed to change a PAGE_EXECONLY permission into PAGE_READONLY_EXEC. However, if BTI or MTE are present, such check does not detect the execute-only pgprot in the presence of PTE_GP (BTI) or MT_NORMAL_TAGGED (MTE), allowing the user to request PROT_EXEC with PROT_BTI or PROT_MTE. Remove the arch_filter_pgprot() function, change the default VM_EXEC permissions to PAGE_READONLY_EXEC and update the protection_map[] array at core_initcall() if EPAN is detected. Signed-off-by: Catalin Marinas Fixes: 18107f8a2df6 ("arm64: Support execute-only permissions with Enhanced PAN") Cc: # 5.13.x Acked-by: Will Deacon Reviewed-by: Vladimir Murzin Tested-by: Vladimir Murzin --- arch/arm64/Kconfig | 3 --- arch/arm64/include/asm/pgtable-prot.h | 4 ++-- arch/arm64/include/asm/pgtable.h | 11 ----------- arch/arm64/mm/mmap.c | 17 +++++++++++++++++ 4 files changed, 19 insertions(+), 16 deletions(-) (limited to 'arch') diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index c7a474f71eb4..f711a8eee6ff 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -1236,9 +1236,6 @@ config HW_PERF_EVENTS def_bool y depends on ARM_PMU -config ARCH_HAS_FILTER_PGPROT - def_bool y - # Supported by clang >= 7.0 config CC_HAVE_SHADOW_CALL_STACK def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18) diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 7032f04c8ac6..b1e1b74d993c 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -92,7 +92,7 @@ extern bool arm64_use_ng_mappings; #define __P001 PAGE_READONLY #define __P010 PAGE_READONLY #define __P011 PAGE_READONLY -#define __P100 PAGE_EXECONLY +#define __P100 PAGE_READONLY_EXEC /* PAGE_EXECONLY if Enhanced PAN */ #define __P101 PAGE_READONLY_EXEC #define __P110 PAGE_READONLY_EXEC #define __P111 PAGE_READONLY_EXEC @@ -101,7 +101,7 @@ extern bool arm64_use_ng_mappings; #define __S001 PAGE_READONLY #define __S010 PAGE_SHARED #define __S011 PAGE_SHARED -#define __S100 PAGE_EXECONLY +#define __S100 PAGE_READONLY_EXEC /* PAGE_EXECONLY if Enhanced PAN */ #define __S101 PAGE_READONLY_EXEC #define __S110 PAGE_SHARED_EXEC #define __S111 PAGE_SHARED_EXEC diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index c4ba047a82d2..94e147e5456c 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -1017,17 +1017,6 @@ static inline bool arch_wants_old_prefaulted_pte(void) } #define arch_wants_old_prefaulted_pte arch_wants_old_prefaulted_pte -static inline pgprot_t arch_filter_pgprot(pgprot_t prot) -{ - if (cpus_have_const_cap(ARM64_HAS_EPAN)) - return prot; - - if (pgprot_val(prot) != pgprot_val(PAGE_EXECONLY)) - return prot; - - return PAGE_READONLY_EXEC; -} - static inline bool pud_sect_supported(void) { return PAGE_SIZE == SZ_4K; diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c index a38f54cd638c..77ada00280d9 100644 --- a/arch/arm64/mm/mmap.c +++ b/arch/arm64/mm/mmap.c @@ -7,8 +7,10 @@ #include #include +#include #include +#include #include /* @@ -38,3 +40,18 @@ int valid_mmap_phys_addr_range(unsigned long pfn, size_t size) { return !(((pfn << PAGE_SHIFT) + size) & ~PHYS_MASK); } + +static int __init adjust_protection_map(void) +{ + /* + * With Enhanced PAN we can honour the execute-only permissions as + * there is no PAN override with such mappings. + */ + if (cpus_have_const_cap(ARM64_HAS_EPAN)) { + protection_map[VM_EXEC] = PAGE_EXECONLY; + protection_map[VM_EXEC | VM_SHARED] = PAGE_EXECONLY; + } + + return 0; +} +arch_initcall(adjust_protection_map); -- cgit v1.2.3 From b859ebedd1e730bbda69142fca87af4e712649a1 Mon Sep 17 00:00:00 2001 From: Paul Semel Date: Tue, 8 Mar 2022 10:30:58 +0100 Subject: arm64: kasan: fix include error in MTE functions Fix `error: expected string literal in 'asm'`. This happens when compiling an ebpf object file that includes `net/net_namespace.h` from linux kernel headers. Include trace: include/net/net_namespace.h:10 include/linux/workqueue.h:9 include/linux/timer.h:8 include/linux/debugobjects.h:6 include/linux/spinlock.h:90 include/linux/workqueue.h:9 arch/arm64/include/asm/spinlock.h:9 arch/arm64/include/generated/asm/qrwlock.h:1 include/asm-generic/qrwlock.h:14 arch/arm64/include/asm/processor.h:33 arch/arm64/include/asm/kasan.h:9 arch/arm64/include/asm/mte-kasan.h:45 arch/arm64/include/asm/mte-def.h:14 Signed-off-by: Paul Semel Fixes: 2cb34276427a ("arm64: kasan: simplify and inline MTE functions") Cc: # 5.12.x Link: https://lore.kernel.org/r/bacb5387-2992-97e4-0c48-1ed925905bee@gmail.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/mte-kasan.h | 1 + 1 file changed, 1 insertion(+) (limited to 'arch') diff --git a/arch/arm64/include/asm/mte-kasan.h b/arch/arm64/include/asm/mte-kasan.h index e4704a403237..a857bcacf0fe 100644 --- a/arch/arm64/include/asm/mte-kasan.h +++ b/arch/arm64/include/asm/mte-kasan.h @@ -5,6 +5,7 @@ #ifndef __ASM_MTE_KASAN_H #define __ASM_MTE_KASAN_H +#include #include #ifndef __ASSEMBLY__ -- cgit v1.2.3