v4.19.13 snapshot.
diff --git a/arch/arm/lib/putuser.S b/arch/arm/lib/putuser.S
new file mode 100644
index 0000000..38d660d
--- /dev/null
+++ b/arch/arm/lib/putuser.S
@@ -0,0 +1,98 @@
+/*
+ * linux/arch/arm/lib/putuser.S
+ *
+ * Copyright (C) 2001 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Idea from x86 version, (C) Copyright 1998 Linus Torvalds
+ *
+ * These functions have a non-standard call interface to make
+ * them more efficient, especially as they return an error
+ * value in addition to the "real" return value.
+ *
+ * __put_user_X
+ *
+ * Inputs: r0 contains the address
+ * r1 contains the address limit, which must be preserved
+ * r2, r3 contains the value
+ * Outputs: r0 is the error code
+ * lr corrupted
+ *
+ * No other registers must be altered. (see <asm/uaccess.h>
+ * for specific ASM register usage).
+ *
+ * Note that ADDR_LIMIT is either 0 or 0xc0000000
+ * Note also that it is intended that __put_user_bad is not global.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+#include <asm/errno.h>
+#include <asm/domain.h>
+
+ENTRY(__put_user_1)
+ check_uaccess r0, 1, r1, ip, __put_user_bad
+1: TUSER(strb) r2, [r0]
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_1)
+
+ENTRY(__put_user_2)
+ check_uaccess r0, 2, r1, ip, __put_user_bad
+ mov ip, r2, lsr #8
+#ifdef CONFIG_THUMB2_KERNEL
+#ifndef __ARMEB__
+2: TUSER(strb) r2, [r0]
+3: TUSER(strb) ip, [r0, #1]
+#else
+2: TUSER(strb) ip, [r0]
+3: TUSER(strb) r2, [r0, #1]
+#endif
+#else /* !CONFIG_THUMB2_KERNEL */
+#ifndef __ARMEB__
+2: TUSER(strb) r2, [r0], #1
+3: TUSER(strb) ip, [r0]
+#else
+2: TUSER(strb) ip, [r0], #1
+3: TUSER(strb) r2, [r0]
+#endif
+#endif /* CONFIG_THUMB2_KERNEL */
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_2)
+
+ENTRY(__put_user_4)
+ check_uaccess r0, 4, r1, ip, __put_user_bad
+4: TUSER(str) r2, [r0]
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_4)
+
+ENTRY(__put_user_8)
+ check_uaccess r0, 8, r1, ip, __put_user_bad
+#ifdef CONFIG_THUMB2_KERNEL
+5: TUSER(str) r2, [r0]
+6: TUSER(str) r3, [r0, #4]
+#else
+5: TUSER(str) r2, [r0], #4
+6: TUSER(str) r3, [r0]
+#endif
+ mov r0, #0
+ ret lr
+ENDPROC(__put_user_8)
+
+__put_user_bad:
+ mov r0, #-EFAULT
+ ret lr
+ENDPROC(__put_user_bad)
+
+.pushsection __ex_table, "a"
+ .long 1b, __put_user_bad
+ .long 2b, __put_user_bad
+ .long 3b, __put_user_bad
+ .long 4b, __put_user_bad
+ .long 5b, __put_user_bad
+ .long 6b, __put_user_bad
+.popsection