diff --git a/arch/powerpc/Kconfig b/arch/powerpc/Kconfig
index 515bd10d32f6d693a0679904724b910f92eb4d67..2711aac24621bc1d14cbf12e1b1b98affae9b09d 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 05274dea310910c333c86771ca9fee4b077f6c6e..296e51c2f066b09dbebf6cedb1d88ef617cbd29d 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 40aec3f00a0523e6ca68c0437ca356ee2bde7cbc..6e85171e513c821fb69fa5a0ee1d350444e7d1f8 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 a9c934f2319b5418dbff6b913a4e4e1635ca5a92..efa219d2136e74a77eb0882395c305d523aadbc2 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 37117ab11584c7a06a9c2ccc86b2fd3a70f278c4..34a5df827b38e58b10d5511b3bb958dd34a8809f 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 03c73b4c6435974278f0f3a07ec20981704403ce..d25adb6ef23507ab89a6a0b2cae1144f14615143 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 32332e24e4216402d21787f883c498fa2bd8e57f..567e0ed45ca8171a6abb4f09815339bd870b48f2 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 19d68a9b5f372a233efe5591016b444c3a5a58cc..91d2c6970bdb9d84d2a7bc835b61fe1b175239f9 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 62735f335bce394ac7d7bb591e152807a5b9b15b..d8c0ce9b255767903fba87d24e8f740039c499f0 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 3eb4cb09749c68f3da26e8edeab46e1b6265942e..c3121b6c8cbdf937ca9d2209a21d2bdd9b30503d 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 0000000000000000000000000000000000000000..42617fcad8289e3e29a8619d98562325e407e22b
--- /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");
+}