From 3d4247fcc938d0ab5cf6fdb752dae07fdeab9736 Mon Sep 17 00:00:00 2001 From: Christophe Leroy Date: Tue, 14 Jan 2020 17:54:00 +0000 Subject: [PATCH] powerpc/32: Add support of KASAN_VMALLOC Add support of KASAN_VMALLOC on PPC32. To allow this, the early shadow covering the VMALLOC space need to be removed once high_memory var is set and before freeing memblock. And the VMALLOC area need to be aligned such that boundaries are covered by a full shadow page. Signed-off-by: Christophe Leroy Signed-off-by: Michael Ellerman Link: https://lore.kernel.org/r/031dec5487bde9b2181c8b3c9800e1879cf98c1a.1579024426.git.christophe.leroy@c-s.fr --- arch/powerpc/Kconfig | 1 + arch/powerpc/include/asm/book3s/32/pgtable.h | 5 +++ arch/powerpc/include/asm/kasan.h | 2 ++ arch/powerpc/include/asm/nohash/32/pgtable.h | 5 +++ arch/powerpc/mm/kasan/kasan_init_32.c | 33 +++++++++++++++++++- arch/powerpc/mm/mem.c | 4 +++ 6 files changed, 49 insertions(+), 1 deletion(-) diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 6093c48976bf..a7f10a1b79f7 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -173,6 +173,7 @@ config PPC select HAVE_ARCH_HUGE_VMAP if PPC_BOOK3S_64 && PPC_RADIX_MMU select HAVE_ARCH_JUMP_LABEL select HAVE_ARCH_KASAN if PPC32 + select HAVE_ARCH_KASAN_VMALLOC if PPC32 select HAVE_ARCH_KGDB select HAVE_ARCH_MMAP_RND_BITS select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT diff --git a/arch/powerpc/include/asm/book3s/32/pgtable.h b/arch/powerpc/include/asm/book3s/32/pgtable.h index 0796533d37dd..5b39c11e884a 100644 --- a/arch/powerpc/include/asm/book3s/32/pgtable.h +++ b/arch/powerpc/include/asm/book3s/32/pgtable.h @@ -193,7 +193,12 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); #else #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))) #endif + +#ifdef CONFIG_KASAN_VMALLOC +#define VMALLOC_END _ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT) +#else #define VMALLOC_END ioremap_bot +#endif #ifndef __ASSEMBLY__ #include diff --git a/arch/powerpc/include/asm/kasan.h b/arch/powerpc/include/asm/kasan.h index 296e51c2f066..fbff9ff9032e 100644 --- a/arch/powerpc/include/asm/kasan.h +++ b/arch/powerpc/include/asm/kasan.h @@ -31,9 +31,11 @@ void kasan_early_init(void); void kasan_mmu_init(void); void kasan_init(void); +void kasan_late_init(void); #else static inline void kasan_init(void) { } static inline void kasan_mmu_init(void) { } +static inline void kasan_late_init(void) { } #endif #endif /* __ASSEMBLY */ diff --git a/arch/powerpc/include/asm/nohash/32/pgtable.h b/arch/powerpc/include/asm/nohash/32/pgtable.h index 552b96eef0c8..60c4d829152e 100644 --- a/arch/powerpc/include/asm/nohash/32/pgtable.h +++ b/arch/powerpc/include/asm/nohash/32/pgtable.h @@ -114,7 +114,12 @@ int map_kernel_page(unsigned long va, phys_addr_t pa, pgprot_t prot); #else #define VMALLOC_START ((((long)high_memory + VMALLOC_OFFSET) & ~(VMALLOC_OFFSET-1))) #endif + +#ifdef CONFIG_KASAN_VMALLOC +#define VMALLOC_END _ALIGN_DOWN(ioremap_bot, PAGE_SIZE << KASAN_SHADOW_SCALE_SHIFT) +#else #define VMALLOC_END ioremap_bot +#endif /* * Bits in a linux-style PTE. These match the bits in the diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c index 0e6ed4413eea..88036fb88350 100644 --- a/arch/powerpc/mm/kasan/kasan_init_32.c +++ b/arch/powerpc/mm/kasan/kasan_init_32.c @@ -129,6 +129,31 @@ static void __init kasan_remap_early_shadow_ro(void) flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END); } +static void __init kasan_unmap_early_shadow_vmalloc(void) +{ + unsigned long k_start = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_START); + unsigned long k_end = (unsigned long)kasan_mem_to_shadow((void *)VMALLOC_END); + unsigned long k_cur; + phys_addr_t pa = __pa(kasan_early_shadow_page); + + if (!early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) { + int ret = kasan_init_shadow_page_tables(k_start, k_end); + + if (ret) + panic("kasan: kasan_init_shadow_page_tables() failed"); + } + for (k_cur = k_start & PAGE_MASK; k_cur < k_end; k_cur += PAGE_SIZE) { + pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(k_cur), k_cur), k_cur); + pte_t *ptep = pte_offset_kernel(pmd, k_cur); + + if ((pte_val(*ptep) & PTE_RPN_MASK) != pa) + continue; + + __set_pte_at(&init_mm, k_cur, ptep, __pte(0), 0); + } + flush_tlb_kernel_range(k_start, k_end); +} + void __init kasan_mmu_init(void) { int ret; @@ -165,7 +190,13 @@ void __init kasan_init(void) pr_info("KASAN init done\n"); } -#ifdef CONFIG_MODULES +void __init kasan_late_init(void) +{ + if (IS_ENABLED(CONFIG_KASAN_VMALLOC)) + kasan_unmap_early_shadow_vmalloc(); +} + +#if defined(CONFIG_MODULES) && !defined(CONFIG_KASAN_VMALLOC) void *module_alloc(unsigned long size) { void *base; diff --git a/arch/powerpc/mm/mem.c b/arch/powerpc/mm/mem.c index f5535eae637f..ef7b1119b2e2 100644 --- a/arch/powerpc/mm/mem.c +++ b/arch/powerpc/mm/mem.c @@ -49,6 +49,7 @@ #include #include #include +#include #include @@ -301,6 +302,9 @@ void __init mem_init(void) high_memory = (void *) __va(max_low_pfn * PAGE_SIZE); set_max_mapnr(max_pfn); + + kasan_late_init(); + memblock_free_all(); #ifdef CONFIG_HIGHMEM