--- zzzz-none-000/linux-4.4.271/mm/kasan/kasan.c	2021-06-03 06:22:09.000000000 +0000
+++ hawkeye-5590-750/linux-4.4.271/mm/kasan/kasan.c	2023-04-19 10:22:30.000000000 +0000
@@ -33,6 +33,8 @@
 #include <linux/vmalloc.h>
 #include <linux/kasan.h>
 
+#include <asm/unaligned.h>
+
 #include "kasan.h"
 #include "../slab.h"
 
@@ -233,6 +235,20 @@
 static __always_inline bool memory_is_poisoned(unsigned long addr, size_t size)
 {
 	if (__builtin_constant_p(size)) {
+		if (IS_ENABLED(CONFIG_ARM)) { /* avoid alignment faults. */
+			switch (size) {
+			case 1:
+			case 2:
+			case 4:
+			case 8:
+				return memory_is_poisoned_1(addr);
+			case 16:
+				return memory_is_poisoned_1(addr)
+					|| memory_is_poisoned_1(addr + 8);
+			default:
+				BUILD_BUG();
+			}
+		}
 		switch (size) {
 		case 1:
 			return memory_is_poisoned_1(addr);
@@ -447,6 +463,18 @@
 	size_t shadow_size;
 	unsigned long shadow_start;
 
+	/* If size < KASAN_SHADOW_SCALE_SHIFT, then size will become ZERO
+	 * on doing size >> KASAN_SHADOW_SCALE_SHIFT. With this,
+	 * shadow_size = round_up(0, PAGE_SIZE) will give ZERO.
+	 * Hence we need to make sure that size >> KASAN_SHADOW_SCALE_SHIFT
+	 * is a non-zero value. Hence if size is less than
+	 * KASAN_SHADOW_SCALE_SIZE, set size as KASAN_SHADOW_SCALE_SIZE, so
+	 * that round_up(size >> KASAN_SHADOW_SCALE_SIZE, PAGE_SIZE) will
+	 * give a non-zero value
+	 */
+	if (size < KASAN_SHADOW_SCALE_SIZE)
+		size = KASAN_SHADOW_SCALE_SIZE;
+
 	shadow_start = (unsigned long)kasan_mem_to_shadow(addr);
 	scaled_size = (size + KASAN_SHADOW_MASK) >> KASAN_SHADOW_SCALE_SHIFT;
 	shadow_size = round_up(scaled_size, PAGE_SIZE);
@@ -478,6 +506,13 @@
 static void register_global(struct kasan_global *global)
 {
 	size_t aligned_size = round_up(global->size, KASAN_SHADOW_SCALE_SIZE);
+	/*
+	 * Currently we do not allocate shadow for vmalloc area
+	 * Skip globals that in modules in vmalloc area.
+	 */
+	if ((unsigned long)global->beg >= VMALLOC_START
+		&& (unsigned long)global->beg < VMALLOC_END)
+		return;
 
 	kasan_unpoison_shadow(global->beg, global->size);