diff options
-rw-r--r-- | arch/powerpc/Kconfig | 1 | ||||
-rw-r--r-- | arch/powerpc/include/asm/kasan.h | 9 | ||||
-rw-r--r-- | arch/powerpc/kernel/head_32.S | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/head_40x.S | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/head_44x.S | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/head_8xx.S | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/head_fsl_booke.S | 3 | ||||
-rw-r--r-- | arch/powerpc/kernel/setup-common.c | 3 | ||||
-rw-r--r-- | arch/powerpc/mm/Makefile | 1 | ||||
-rw-r--r-- | arch/powerpc/mm/init_32.c | 3 | ||||
-rw-r--r-- | arch/powerpc/mm/kasan/kasan_init_32.c | 156 |
11 files changed, 188 insertions, 0 deletions
diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig index 515bd10d32f6..2711aac24621 100644 --- a/arch/powerpc/Kconfig +++ b/arch/powerpc/Kconfig @@ -173,6 +173,7 @@ config PPC select GENERIC_TIME_VSYSCALL select HAVE_ARCH_AUDITSYSCALL select HAVE_ARCH_JUMP_LABEL + select HAVE_ARCH_KASAN 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/kasan.h b/arch/powerpc/include/asm/kasan.h index 05274dea3109..296e51c2f066 100644 --- a/arch/powerpc/include/asm/kasan.h +++ b/arch/powerpc/include/asm/kasan.h @@ -27,5 +27,14 @@ #define KASAN_SHADOW_SIZE (KASAN_SHADOW_END - KASAN_SHADOW_START) +#ifdef CONFIG_KASAN +void kasan_early_init(void); +void kasan_mmu_init(void); +void kasan_init(void); +#else +static inline void kasan_init(void) { } +static inline void kasan_mmu_init(void) { } +#endif + #endif /* __ASSEMBLY */ #endif diff --git a/arch/powerpc/kernel/head_32.S b/arch/powerpc/kernel/head_32.S index 40aec3f00a05..6e85171e513c 100644 --- a/arch/powerpc/kernel/head_32.S +++ b/arch/powerpc/kernel/head_32.S @@ -969,6 +969,9 @@ start_here: * Do early platform-specific initialization, * and set up the MMU. */ +#ifdef CONFIG_KASAN + bl kasan_early_init +#endif li r3,0 mr r4,r31 bl machine_init diff --git a/arch/powerpc/kernel/head_40x.S b/arch/powerpc/kernel/head_40x.S index a9c934f2319b..efa219d2136e 100644 --- a/arch/powerpc/kernel/head_40x.S +++ b/arch/powerpc/kernel/head_40x.S @@ -848,6 +848,9 @@ start_here: /* * Decide what sort of machine this is and initialize the MMU. */ +#ifdef CONFIG_KASAN + bl kasan_early_init +#endif li r3,0 mr r4,r31 bl machine_init diff --git a/arch/powerpc/kernel/head_44x.S b/arch/powerpc/kernel/head_44x.S index 37117ab11584..34a5df827b38 100644 --- a/arch/powerpc/kernel/head_44x.S +++ b/arch/powerpc/kernel/head_44x.S @@ -203,6 +203,9 @@ _ENTRY(_start); /* * Decide what sort of machine this is and initialize the MMU. */ +#ifdef CONFIG_KASAN + bl kasan_early_init +#endif li r3,0 mr r4,r31 bl machine_init diff --git a/arch/powerpc/kernel/head_8xx.S b/arch/powerpc/kernel/head_8xx.S index 03c73b4c6435..d25adb6ef235 100644 --- a/arch/powerpc/kernel/head_8xx.S +++ b/arch/powerpc/kernel/head_8xx.S @@ -853,6 +853,9 @@ start_here: /* * Decide what sort of machine this is and initialize the MMU. */ +#ifdef CONFIG_KASAN + bl kasan_early_init +#endif li r3,0 mr r4,r31 bl machine_init diff --git a/arch/powerpc/kernel/head_fsl_booke.S b/arch/powerpc/kernel/head_fsl_booke.S index 32332e24e421..567e0ed45ca8 100644 --- a/arch/powerpc/kernel/head_fsl_booke.S +++ b/arch/powerpc/kernel/head_fsl_booke.S @@ -268,6 +268,9 @@ set_ivor: /* * Decide what sort of machine this is and initialize the MMU. */ +#ifdef CONFIG_KASAN + bl kasan_early_init +#endif mr r3,r30 mr r4,r31 bl machine_init diff --git a/arch/powerpc/kernel/setup-common.c b/arch/powerpc/kernel/setup-common.c index 19d68a9b5f37..91d2c6970bdb 100644 --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -67,6 +67,7 @@ #include <asm/livepatch.h> #include <asm/mmu_context.h> #include <asm/cpu_has_feature.h> +#include <asm/kasan.h> #include "setup.h" @@ -871,6 +872,8 @@ static void smp_setup_pacas(void) */ void __init setup_arch(char **cmdline_p) { + kasan_init(); + *cmdline_p = boot_command_line; /* Set a half-reasonable default so udelay does something sensible */ diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile index 62735f335bce..d8c0ce9b2557 100644 --- a/arch/powerpc/mm/Makefile +++ b/arch/powerpc/mm/Makefile @@ -26,3 +26,4 @@ obj-$(CONFIG_NOT_COHERENT_CACHE) += dma-noncoherent.o obj-$(CONFIG_HIGHMEM) += highmem.o obj-$(CONFIG_PPC_COPRO_BASE) += copro_fault.o obj-$(CONFIG_PPC_PTDUMP) += ptdump/ +obj-$(CONFIG_KASAN) += kasan/ diff --git a/arch/powerpc/mm/init_32.c b/arch/powerpc/mm/init_32.c index 3eb4cb09749c..c3121b6c8cbd 100644 --- a/arch/powerpc/mm/init_32.c +++ b/arch/powerpc/mm/init_32.c @@ -46,6 +46,7 @@ #include <asm/sections.h> #include <asm/hugetlb.h> #include <asm/kup.h> +#include <asm/kasan.h> #include <mm/mmu_decl.h> @@ -179,6 +180,8 @@ void __init MMU_init(void) btext_unmap(); #endif + kasan_mmu_init(); + setup_kup(); /* Shortly after that, the entire linear mapping will be available */ diff --git a/arch/powerpc/mm/kasan/kasan_init_32.c b/arch/powerpc/mm/kasan/kasan_init_32.c new file mode 100644 index 000000000000..42617fcad828 --- /dev/null +++ b/arch/powerpc/mm/kasan/kasan_init_32.c @@ -0,0 +1,156 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define DISABLE_BRANCH_PROFILING + +#include <linux/kasan.h> +#include <linux/printk.h> +#include <linux/memblock.h> +#include <linux/sched/task.h> +#include <linux/vmalloc.h> +#include <asm/pgalloc.h> +#include <asm/code-patching.h> +#include <mm/mmu_decl.h> + +static void kasan_populate_pte(pte_t *ptep, pgprot_t prot) +{ + unsigned long va = (unsigned long)kasan_early_shadow_page; + phys_addr_t pa = __pa(kasan_early_shadow_page); + int i; + + for (i = 0; i < PTRS_PER_PTE; i++, ptep++) + __set_pte_at(&init_mm, va, ptep, pfn_pte(PHYS_PFN(pa), prot), 0); +} + +static int kasan_init_shadow_page_tables(unsigned long k_start, unsigned long k_end) +{ + pmd_t *pmd; + unsigned long k_cur, k_next; + + pmd = pmd_offset(pud_offset(pgd_offset_k(k_start), k_start), k_start); + + for (k_cur = k_start; k_cur != k_end; k_cur = k_next, pmd++) { + pte_t *new; + + k_next = pgd_addr_end(k_cur, k_end); + if ((void *)pmd_page_vaddr(*pmd) != kasan_early_shadow_pte) + continue; + + new = pte_alloc_one_kernel(&init_mm); + + if (!new) + return -ENOMEM; + kasan_populate_pte(new, PAGE_KERNEL_RO); + pmd_populate_kernel(&init_mm, pmd, new); + } + return 0; +} + +static void __ref *kasan_get_one_page(void) +{ + if (slab_is_available()) + return (void *)__get_free_page(GFP_KERNEL | __GFP_ZERO); + + return memblock_alloc(PAGE_SIZE, PAGE_SIZE); +} + +static int __ref kasan_init_region(void *start, size_t size) +{ + unsigned long k_start = (unsigned long)kasan_mem_to_shadow(start); + unsigned long k_end = (unsigned long)kasan_mem_to_shadow(start + size); + unsigned long k_cur; + int ret; + void *block = NULL; + + ret = kasan_init_shadow_page_tables(k_start, k_end); + if (ret) + return ret; + + if (!slab_is_available()) + block = memblock_alloc(k_end - k_start, PAGE_SIZE); + + for (k_cur = k_start; k_cur < k_end; k_cur += PAGE_SIZE) { + pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(k_cur), k_cur), k_cur); + void *va = block ? block + k_cur - k_start : kasan_get_one_page(); + pte_t pte = pfn_pte(PHYS_PFN(__pa(va)), PAGE_KERNEL); + + if (!va) + return -ENOMEM; + + __set_pte_at(&init_mm, k_cur, pte_offset_kernel(pmd, k_cur), pte, 0); + } + flush_tlb_kernel_range(k_start, k_end); + return 0; +} + +static void __init kasan_remap_early_shadow_ro(void) +{ + kasan_populate_pte(kasan_early_shadow_pte, PAGE_KERNEL_RO); + + flush_tlb_kernel_range(KASAN_SHADOW_START, KASAN_SHADOW_END); +} + +void __init kasan_mmu_init(void) +{ + int ret; + struct memblock_region *reg; + + for_each_memblock(memory, reg) { + phys_addr_t base = reg->base; + phys_addr_t top = min(base + reg->size, total_lowmem); + + if (base >= top) + continue; + + ret = kasan_init_region(__va(base), top - base); + if (ret) + panic("kasan: kasan_init_region() failed"); + } +} + +void __init kasan_init(void) +{ + kasan_remap_early_shadow_ro(); + + clear_page(kasan_early_shadow_page); + + /* At this point kasan is fully initialized. Enable error messages */ + init_task.kasan_depth = 0; + pr_info("KASAN init done\n"); +} + +#ifdef CONFIG_MODULES +void *module_alloc(unsigned long size) +{ + void *base = vmalloc_exec(size); + + if (!base) + return NULL; + + if (!kasan_init_region(base, size)) + return base; + + vfree(base); + + return NULL; +} +#endif + +void __init kasan_early_init(void) +{ + unsigned long addr = KASAN_SHADOW_START; + unsigned long end = KASAN_SHADOW_END; + unsigned long next; + pmd_t *pmd = pmd_offset(pud_offset(pgd_offset_k(addr), addr), addr); + + BUILD_BUG_ON(KASAN_SHADOW_START & ~PGDIR_MASK); + + kasan_populate_pte(kasan_early_shadow_pte, PAGE_KERNEL); + + do { + next = pgd_addr_end(addr, end); + pmd_populate_kernel(&init_mm, pmd, kasan_early_shadow_pte); + } while (pmd++, addr = next, addr != end); + + if (early_mmu_has_feature(MMU_FTR_HPTE_TABLE)) + WARN(true, "KASAN not supported on hash 6xx"); +} |