From 7c302cfbee1f6cc23d831be4b6cf42f331019e68 Mon Sep 17 00:00:00 2001 From: Joey Gouly Date: Tue, 6 Jun 2023 15:58:51 +0100 Subject: arm64: add PTE_WRITE to PROT_SECT_NORMAL With PIE enabled, PROT_SECT_NORMAL would map onto PAGE_KERNEL_RO. Add PTE_WRITE so that this maps onto PAGE_KERNEL, so that it is writable. Without PIE, this should enable DBM for PROT_SECT_NORMAL. However PTE_RDONLY is already cleared, so the DBM mechanism is not used, and it is always writable, so this is functionally equivalent. Signed-off-by: Joey Gouly Cc: Will Deacon Cc: Mark Rutland Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20230606145859.697944-13-joey.gouly@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/pgtable-prot.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'arch/arm64/include/asm/pgtable-prot.h') diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index 9b165117a454..d26d0b427c0a 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -60,7 +60,7 @@ extern bool arm64_use_ng_mappings; #define PROT_NORMAL_TAGGED (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED)) #define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE)) -#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL)) +#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PTE_WRITE | PMD_ATTRINDX(MT_NORMAL)) #define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL)) #define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL)) -- cgit v1.2.3 From fa4cdccaa58224a12591f2c045c24abc5251bb9d Mon Sep 17 00:00:00 2001 From: Joey Gouly Date: Tue, 6 Jun 2023 15:58:52 +0100 Subject: arm64: reorganise PAGE_/PROT_ macros Make these macros available to assembly code, so they can be re-used by the PIE initialisation code. This involves adding some extra macros, prepended with _ that are the raw values not `pgprot` values. A dummy value for PTE_MAYBE_NG is also provided, for use in assembly. Signed-off-by: Joey Gouly Cc: Will Deacon Cc: Mark Rutland Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20230606145859.697944-14-joey.gouly@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/pgtable-prot.h | 72 +++++++++++++++++++++-------------- 1 file changed, 44 insertions(+), 28 deletions(-) (limited to 'arch/arm64/include/asm/pgtable-prot.h') diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index d26d0b427c0a..a45af0a22b25 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -27,6 +27,40 @@ */ #define PMD_PRESENT_INVALID (_AT(pteval_t, 1) << 59) /* only when !PMD_SECT_VALID */ +#define _PROT_DEFAULT (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED) +#define _PROT_SECT_DEFAULT (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S) + +#define PROT_DEFAULT (_PROT_DEFAULT | PTE_MAYBE_NG) +#define PROT_SECT_DEFAULT (_PROT_SECT_DEFAULT | PMD_MAYBE_NG) + +#define PROT_DEVICE_nGnRnE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE)) +#define PROT_DEVICE_nGnRE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE)) +#define PROT_NORMAL_NC (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_NC)) +#define PROT_NORMAL (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL)) +#define PROT_NORMAL_TAGGED (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED)) + +#define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE)) +#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PTE_WRITE | PMD_ATTRINDX(MT_NORMAL)) +#define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL)) + +#define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL)) + +#define _PAGE_KERNEL (PROT_NORMAL) +#define _PAGE_KERNEL_RO ((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY) +#define _PAGE_KERNEL_ROX ((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY) +#define _PAGE_KERNEL_EXEC (PROT_NORMAL & ~PTE_PXN) +#define _PAGE_KERNEL_EXEC_CONT ((PROT_NORMAL & ~PTE_PXN) | PTE_CONT) + +#define _PAGE_SHARED (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE) +#define _PAGE_SHARED_EXEC (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_WRITE) +#define _PAGE_READONLY (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN) +#define _PAGE_READONLY_EXEC (_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN) +#define _PAGE_EXECONLY (_PAGE_DEFAULT | PTE_RDONLY | PTE_NG | PTE_PXN) + +#ifdef __ASSEMBLY__ +#define PTE_MAYBE_NG 0 +#endif + #ifndef __ASSEMBLY__ #include @@ -34,9 +68,6 @@ extern bool arm64_use_ng_mappings; -#define _PROT_DEFAULT (PTE_TYPE_PAGE | PTE_AF | PTE_SHARED) -#define _PROT_SECT_DEFAULT (PMD_TYPE_SECT | PMD_SECT_AF | PMD_SECT_S) - #define PTE_MAYBE_NG (arm64_use_ng_mappings ? PTE_NG : 0) #define PMD_MAYBE_NG (arm64_use_ng_mappings ? PMD_SECT_NG : 0) @@ -50,26 +81,11 @@ extern bool arm64_use_ng_mappings; #define PTE_MAYBE_GP 0 #endif -#define PROT_DEFAULT (_PROT_DEFAULT | PTE_MAYBE_NG) -#define PROT_SECT_DEFAULT (_PROT_SECT_DEFAULT | PMD_MAYBE_NG) - -#define PROT_DEVICE_nGnRnE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRnE)) -#define PROT_DEVICE_nGnRE (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_DEVICE_nGnRE)) -#define PROT_NORMAL_NC (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_NC)) -#define PROT_NORMAL (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL)) -#define PROT_NORMAL_TAGGED (PROT_DEFAULT | PTE_PXN | PTE_UXN | PTE_WRITE | PTE_ATTRINDX(MT_NORMAL_TAGGED)) - -#define PROT_SECT_DEVICE_nGnRE (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PMD_ATTRINDX(MT_DEVICE_nGnRE)) -#define PROT_SECT_NORMAL (PROT_SECT_DEFAULT | PMD_SECT_PXN | PMD_SECT_UXN | PTE_WRITE | PMD_ATTRINDX(MT_NORMAL)) -#define PROT_SECT_NORMAL_EXEC (PROT_SECT_DEFAULT | PMD_SECT_UXN | PMD_ATTRINDX(MT_NORMAL)) - -#define _PAGE_DEFAULT (_PROT_DEFAULT | PTE_ATTRINDX(MT_NORMAL)) - -#define PAGE_KERNEL __pgprot(PROT_NORMAL) -#define PAGE_KERNEL_RO __pgprot((PROT_NORMAL & ~PTE_WRITE) | PTE_RDONLY) -#define PAGE_KERNEL_ROX __pgprot((PROT_NORMAL & ~(PTE_WRITE | PTE_PXN)) | PTE_RDONLY) -#define PAGE_KERNEL_EXEC __pgprot(PROT_NORMAL & ~PTE_PXN) -#define PAGE_KERNEL_EXEC_CONT __pgprot((PROT_NORMAL & ~PTE_PXN) | PTE_CONT) +#define PAGE_KERNEL __pgprot(_PAGE_KERNEL) +#define PAGE_KERNEL_RO __pgprot(_PAGE_KERNEL_RO) +#define PAGE_KERNEL_ROX __pgprot(_PAGE_KERNEL_ROX) +#define PAGE_KERNEL_EXEC __pgprot(_PAGE_KERNEL_EXEC) +#define PAGE_KERNEL_EXEC_CONT __pgprot(_PAGE_KERNEL_EXEC_CONT) #define PAGE_S2_MEMATTR(attr, has_fwb) \ ({ \ @@ -83,11 +99,11 @@ extern bool arm64_use_ng_mappings; #define PAGE_NONE __pgprot(((_PAGE_DEFAULT) & ~PTE_VALID) | PTE_PROT_NONE | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN) /* shared+writable pages are clean by default, hence PTE_RDONLY|PTE_WRITE */ -#define PAGE_SHARED __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN | PTE_WRITE) -#define PAGE_SHARED_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_WRITE) -#define PAGE_READONLY __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN | PTE_UXN) -#define PAGE_READONLY_EXEC __pgprot(_PAGE_DEFAULT | PTE_USER | PTE_RDONLY | PTE_NG | PTE_PXN) -#define PAGE_EXECONLY __pgprot(_PAGE_DEFAULT | PTE_RDONLY | PTE_NG | PTE_PXN) +#define PAGE_SHARED __pgprot(_PAGE_SHARED) +#define PAGE_SHARED_EXEC __pgprot(_PAGE_SHARED_EXEC) +#define PAGE_READONLY __pgprot(_PAGE_READONLY) +#define PAGE_READONLY_EXEC __pgprot(_PAGE_READONLY_EXEC) +#define PAGE_EXECONLY __pgprot(_PAGE_EXECONLY) #endif /* __ASSEMBLY__ */ -- cgit v1.2.3 From eeda243dfeb996fe236c624796630c16237a18d6 Mon Sep 17 00:00:00 2001 From: Joey Gouly Date: Tue, 6 Jun 2023 15:58:54 +0100 Subject: arm64: add encodings of PIRx_ELx registers The encodings used in the permission indirection registers means that the values that Linux puts in the PTEs do not need to be changed. The E0 values are replicated in E1, with the execute permissions removed. This is needed as the futex operations access user mappings with privileged loads/stores. Signed-off-by: Joey Gouly Cc: Will Deacon Reviewed-by: Catalin Marinas Link: https://lore.kernel.org/r/20230606145859.697944-16-joey.gouly@arm.com Signed-off-by: Catalin Marinas --- arch/arm64/include/asm/pgtable-hwdef.h | 8 ++++++ arch/arm64/include/asm/pgtable-prot.h | 50 ++++++++++++++++++++++++++++++++++ 2 files changed, 58 insertions(+) (limited to 'arch/arm64/include/asm/pgtable-prot.h') diff --git a/arch/arm64/include/asm/pgtable-hwdef.h b/arch/arm64/include/asm/pgtable-hwdef.h index f658aafc47df..e4944d517c99 100644 --- a/arch/arm64/include/asm/pgtable-hwdef.h +++ b/arch/arm64/include/asm/pgtable-hwdef.h @@ -170,6 +170,14 @@ #define PTE_ATTRINDX(t) (_AT(pteval_t, (t)) << 2) #define PTE_ATTRINDX_MASK (_AT(pteval_t, 7) << 2) +/* + * PIIndex[3:0] encoding (Permission Indirection Extension) + */ +#define PTE_PI_IDX_0 6 /* AP[1], USER */ +#define PTE_PI_IDX_1 51 /* DBM */ +#define PTE_PI_IDX_2 53 /* PXN */ +#define PTE_PI_IDX_3 54 /* UXN */ + /* * Memory Attribute override for Stage-2 (MemAttr[3:0]) */ diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h index a45af0a22b25..eed814b00a38 100644 --- a/arch/arm64/include/asm/pgtable-prot.h +++ b/arch/arm64/include/asm/pgtable-prot.h @@ -107,4 +107,54 @@ extern bool arm64_use_ng_mappings; #endif /* __ASSEMBLY__ */ +#define pte_pi_index(pte) ( \ + ((pte & BIT(PTE_PI_IDX_3)) >> (PTE_PI_IDX_3 - 3)) | \ + ((pte & BIT(PTE_PI_IDX_2)) >> (PTE_PI_IDX_2 - 2)) | \ + ((pte & BIT(PTE_PI_IDX_1)) >> (PTE_PI_IDX_1 - 1)) | \ + ((pte & BIT(PTE_PI_IDX_0)) >> (PTE_PI_IDX_0 - 0))) + +/* + * Page types used via Permission Indirection Extension (PIE). PIE uses + * the USER, DBM, PXN and UXN bits to to generate an index which is used + * to look up the actual permission in PIR_ELx and PIRE0_EL1. We define + * combinations we use on non-PIE systems with the same encoding, for + * convenience these are listed here as comments as are the unallocated + * encodings. + */ + +/* 0: PAGE_DEFAULT */ +/* 1: PTE_USER */ +/* 2: PTE_WRITE */ +/* 3: PTE_WRITE | PTE_USER */ +/* 4: PAGE_EXECONLY PTE_PXN */ +/* 5: PAGE_READONLY_EXEC PTE_PXN | PTE_USER */ +/* 6: PTE_PXN | PTE_WRITE */ +/* 7: PAGE_SHARED_EXEC PTE_PXN | PTE_WRITE | PTE_USER */ +/* 8: PAGE_KERNEL_ROX PTE_UXN */ +/* 9: PTE_UXN | PTE_USER */ +/* a: PAGE_KERNEL_EXEC PTE_UXN | PTE_WRITE */ +/* b: PTE_UXN | PTE_WRITE | PTE_USER */ +/* c: PAGE_KERNEL_RO PTE_UXN | PTE_PXN */ +/* d: PAGE_READONLY PTE_UXN | PTE_PXN | PTE_USER */ +/* e: PAGE_KERNEL PTE_UXN | PTE_PXN | PTE_WRITE */ +/* f: PAGE_SHARED PTE_UXN | PTE_PXN | PTE_WRITE | PTE_USER */ + +#define PIE_E0 ( \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_X_O) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_RX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RWX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW)) + +#define PIE_E1 ( \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_EXECONLY), PIE_NONE_O) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY_EXEC), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED_EXEC), PIE_RW) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_READONLY), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_SHARED), PIE_RW) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_ROX), PIE_RX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_EXEC), PIE_RWX) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL_RO), PIE_R) | \ + PIRx_ELx_PERM(pte_pi_index(_PAGE_KERNEL), PIE_RW)) + #endif /* __ASM_PGTABLE_PROT_H */ -- cgit v1.2.3