diff --git a/arch/arm64/lib/copy_from_user.S b/arch/arm64/lib/copy_from_user.S
index 96b22c0fa34328053c8838a870c162e65a9f8312..7cd6eeaa216cf51180608a6ab755883b7cffa109 100644
--- a/arch/arm64/lib/copy_from_user.S
+++ b/arch/arm64/lib/copy_from_user.S
@@ -39,7 +39,7 @@
 	.endm
 
 	.macro ldrh1 ptr, regB, val
-	uao_user_alternative 9998f, ldrh, ldtrh, \ptr, \regB, \val
+	uao_user_alternative 9997f, ldrh, ldtrh, \ptr, \regB, \val
 	.endm
 
 	.macro strh1 ptr, regB, val
@@ -47,7 +47,7 @@
 	.endm
 
 	.macro ldr1 ptr, regB, val
-	uao_user_alternative 9998f, ldr, ldtr, \ptr, \regB, \val
+	uao_user_alternative 9997f, ldr, ldtr, \ptr, \regB, \val
 	.endm
 
 	.macro str1 ptr, regB, val
@@ -55,7 +55,7 @@
 	.endm
 
 	.macro ldp1 ptr, regB, regC, val
-	uao_ldp 9998f, \ptr, \regB, \regC, \val
+	uao_ldp 9997f, \ptr, \regB, \regC, \val
 	.endm
 
 	.macro stp1 ptr, regB, regC, val
@@ -63,9 +63,11 @@
 	.endm
 
 end	.req	x5
+srcin	.req	x15
 ENTRY(__arch_copy_from_user)
 	uaccess_enable_not_uao x3, x4, x5
 	add	end, x0, x2
+	mov	srcin, x1
 #include "copy_template.S"
 	uaccess_disable_not_uao x3, x4
 	mov	x0, #0				// Nothing to copy
@@ -74,6 +76,11 @@ ENDPROC(__arch_copy_from_user)
 
 	.section .fixup,"ax"
 	.align	2
+9997:	cmp	dst, dstin
+	b.ne	9998f
+	// Before being absolutely sure we couldn't copy anything, try harder
+USER(9998f, ldtrb tmp1w, [srcin])
+	strb	tmp1w, [dst], #1
 9998:	sub	x0, end, dst			// bytes not copied
 	uaccess_disable_not_uao x3, x4
 	ret
diff --git a/arch/arm64/lib/copy_in_user.S b/arch/arm64/lib/copy_in_user.S
index e56c705f1f2361ba4e52274ee506bab201a48e4d..b20d3a0b32374c0050afe3393557464bbdfc8ca5 100644
--- a/arch/arm64/lib/copy_in_user.S
+++ b/arch/arm64/lib/copy_in_user.S
@@ -40,34 +40,36 @@
 	.endm
 
 	.macro ldrh1 ptr, regB, val
-	uao_user_alternative 9998f, ldrh, ldtrh, \ptr, \regB, \val
+	uao_user_alternative 9997f, ldrh, ldtrh, \ptr, \regB, \val
 	.endm
 
 	.macro strh1 ptr, regB, val
-	uao_user_alternative 9998f, strh, sttrh, \ptr, \regB, \val
+	uao_user_alternative 9997f, strh, sttrh, \ptr, \regB, \val
 	.endm
 
 	.macro ldr1 ptr, regB, val
-	uao_user_alternative 9998f, ldr, ldtr, \ptr, \regB, \val
+	uao_user_alternative 9997f, ldr, ldtr, \ptr, \regB, \val
 	.endm
 
 	.macro str1 ptr, regB, val
-	uao_user_alternative 9998f, str, sttr, \ptr, \regB, \val
+	uao_user_alternative 9997f, str, sttr, \ptr, \regB, \val
 	.endm
 
 	.macro ldp1 ptr, regB, regC, val
-	uao_ldp 9998f, \ptr, \regB, \regC, \val
+	uao_ldp 9997f, \ptr, \regB, \regC, \val
 	.endm
 
 	.macro stp1 ptr, regB, regC, val
-	uao_stp 9998f, \ptr, \regB, \regC, \val
+	uao_stp 9997f, \ptr, \regB, \regC, \val
 	.endm
 
 end	.req	x5
+srcin	.req	x15
 
 ENTRY(__arch_copy_in_user)
 	uaccess_enable_not_uao x3, x4, x5
 	add	end, x0, x2
+	mov	srcin, x1
 #include "copy_template.S"
 	uaccess_disable_not_uao x3, x4
 	mov	x0, #0
@@ -76,6 +78,12 @@ ENDPROC(__arch_copy_in_user)
 
 	.section .fixup,"ax"
 	.align	2
+9997:	cmp	dst, dstin
+	b.ne	9998f
+	// Before being absolutely sure we couldn't copy anything, try harder
+USER(9998f, ldtrb tmp1w, [srcin])
+USER(9998f, sttrb tmp1w, [dst])
+	add	dst, dst, #1
 9998:	sub	x0, end, dst			// bytes not copied
 	uaccess_disable_not_uao x3, x4
 	ret
diff --git a/arch/arm64/lib/copy_to_user.S b/arch/arm64/lib/copy_to_user.S
index 769133236f4ade87ab5abd1f575abb0ae1e19f3f..84b7a16e82b5d742d5971d55885c39e691628e4e 100644
--- a/arch/arm64/lib/copy_to_user.S
+++ b/arch/arm64/lib/copy_to_user.S
@@ -42,7 +42,7 @@
 	.endm
 
 	.macro strh1 ptr, regB, val
-	uao_user_alternative 9998f, strh, sttrh, \ptr, \regB, \val
+	uao_user_alternative 9997f, strh, sttrh, \ptr, \regB, \val
 	.endm
 
 	.macro ldr1 ptr, regB, val
@@ -50,7 +50,7 @@
 	.endm
 
 	.macro str1 ptr, regB, val
-	uao_user_alternative 9998f, str, sttr, \ptr, \regB, \val
+	uao_user_alternative 9997f, str, sttr, \ptr, \regB, \val
 	.endm
 
 	.macro ldp1 ptr, regB, regC, val
@@ -58,13 +58,15 @@
 	.endm
 
 	.macro stp1 ptr, regB, regC, val
-	uao_stp 9998f, \ptr, \regB, \regC, \val
+	uao_stp 9997f, \ptr, \regB, \regC, \val
 	.endm
 
 end	.req	x5
+srcin	.req	x15
 ENTRY(__arch_copy_to_user)
 	uaccess_enable_not_uao x3, x4, x5
 	add	end, x0, x2
+	mov	srcin, x1
 #include "copy_template.S"
 	uaccess_disable_not_uao x3, x4
 	mov	x0, #0
@@ -92,6 +94,12 @@ ENDPROC(__arch_copy_to_user_generic_read)
 
 	.section .fixup,"ax"
 	.align	2
+9997:	cmp	dst, dstin
+	b.ne	9998f
+	// Before being absolutely sure we couldn't copy anything, try harder
+	ldrb	tmp1w, [srcin]
+USER(9998f, sttrb tmp1w, [dst])
+	add	dst, dst, #1
 9998:	sub	x0, end, dst			// bytes not copied
 	uaccess_disable_not_uao x3, x4
 	ret