diff --git a/target/mips/tcg/sysemu/mips-semi.c b/target/mips/tcg/sysemu/mips-semi.c
index ae4b8849b1..b54267681e 100644
--- a/target/mips/tcg/sysemu/mips-semi.c
+++ b/target/mips/tcg/sysemu/mips-semi.c
@@ -198,21 +198,6 @@ static void uhi_fstat_cb(CPUState *cs, uint64_t ret, int err)
     uhi_cb(cs, ret, err);
 }
 
-static int copy_argn_to_target(CPUMIPSState *env, int arg_num,
-                               target_ulong vaddr)
-{
-    int strsize = strlen(semihosting_get_arg(arg_num)) + 1;
-    char *dst = lock_user(VERIFY_WRITE, vaddr, strsize, 0);
-    if (!dst) {
-        report_fault(env);
-    }
-
-    strcpy(dst, semihosting_get_arg(arg_num));
-
-    unlock_user(dst, vaddr, strsize);
-    return 0;
-}
-
 #define GET_TARGET_STRING(p, addr)              \
     do {                                        \
         p = lock_user_string(addr);             \
@@ -285,18 +270,31 @@ void mips_semihosting(CPUMIPSState *env)
         gpr[2] = semihosting_get_argc();
         break;
     case UHI_argnlen:
-        if (gpr[4] >= semihosting_get_argc()) {
-            gpr[2] = -1;
-            return;
+        {
+            const char *s = semihosting_get_arg(gpr[4]);
+            gpr[2] = s ? strlen(s) : -1;
         }
-        gpr[2] = strlen(semihosting_get_arg(gpr[4]));
         break;
     case UHI_argn:
-        if (gpr[4] >= semihosting_get_argc()) {
-            gpr[2] = -1;
-            return;
+        {
+            const char *s = semihosting_get_arg(gpr[4]);
+            target_ulong addr;
+            size_t len;
+
+            if (!s) {
+                gpr[2] = -1;
+                break;
+            }
+            len = strlen(s) + 1;
+            addr = gpr[5];
+            p = lock_user(VERIFY_WRITE, addr, len, 0);
+            if (!p) {
+                report_fault(env);
+            }
+            memcpy(p, s, len);
+            unlock_user(p, addr, len);
+            gpr[2] = 0;
         }
-        gpr[2] = copy_argn_to_target(env, gpr[4], gpr[5]);
         break;
 
     case UHI_plog: