1 files changed, 9 insertions, 0 deletions

diff --git a/arch/arm64/mm/kasan_init.c b/arch/arm64/mm/kasan_init.c
index cf038c7d9fa9..cab7a5be40aa 100644
--- a/arch/arm64/mm/kasan_init.c
+++ b/arch/arm64/mm/kasan_init.c
@@ -120,6 +120,7 @@ static void __init cpu_set_ttbr1(unsigned long ttbr1)
 void __init kasan_init(void)
 {
         struct memblock_region *reg;
+        int i;
 
         /*
          * We are going to perform proper setup of shadow memory.
@@ -155,6 +156,14 @@ void __init kasan_init(void)
                                 pfn_to_nid(virt_to_pfn(start)));
         }
 
+        /*
+         * KAsan may reuse the contents of kasan_zero_pte directly, so we
+         * should make sure that it maps the zero page read-only.
+         */
+        for (i = 0; i < PTRS_PER_PTE; i++)
+                set_pte(&kasan_zero_pte[i],
+                        pfn_pte(virt_to_pfn(kasan_zero_page), PAGE_KERNEL_RO));
+
         memset(kasan_zero_page, 0, PAGE_SIZE);
         cpu_set_ttbr1(__pa(swapper_pg_dir));
         flush_tlb_all();