From 0018bdd249eb8e76bea56f7826dcb81e2e1c918a Mon Sep 17 00:00:00 2001
From: Toby Jaffey <toby@ringtailsoftware.co.uk>
Date: Sat, 13 Dec 2025 19:12:24 +0000
Subject: [PATCH] Add test of reading cstring syscall argument which never
 terminates before hitting end of ram

---
 test/common/makefile-rom.common |  1 +
 test/syscall_args/rom/rom.c     |  8 ++++++++
 test/syscall_args/shared.h      |  1 +
 test/syscall_args/test/tests.c  | 21 +++++++++++++++++++++
 4 files changed, 31 insertions(+)

diff --git a/test/common/makefile-rom.common b/test/common/makefile-rom.common
index 77d5026..0f0bd0a 100644
--- a/test/common/makefile-rom.common
+++ b/test/common/makefile-rom.common
@@ -2,6 +2,7 @@ TOPDIR=../../../
 PROJECT:=$(shell basename ${PWD})
 SRCS=${PROJECT}.c ${TOPDIR}/apps/common/crt0.S
 OPT=-O0
+CFLAGS=-DUVM32_MEMORY_SIZE=16384
 all: all_common
 	@# Convert ROM to C file and header
 	@xxd -i ${PROJECT}.bin > ${PROJECT}-header.c
diff --git a/test/syscall_args/rom/rom.c b/test/syscall_args/rom/rom.c
index d82e5aa..7ef7f85 100644
--- a/test/syscall_args/rom/rom.c
+++ b/test/syscall_args/rom/rom.c
@@ -42,6 +42,11 @@ void syscall_gh_test(void) {
     syscall((uint32_t)SYSCALL_H, (uint32_t)buf, 32);
 }
 
+void syscall_i_test(void) {
+    char *p = "hello";  // runner will overwrite memory
+    syscall((uint32_t)SYSCALL_I, (uint32_t)p, 0);
+}
+
 void main(void) {
     switch(syscall(SYSCALL_PICKTEST, 0, 0)) {
         case SYSCALL_A:
@@ -62,6 +67,9 @@ void main(void) {
         case SYSCALL_G:
             syscall_gh_test();
         break;
+        case SYSCALL_I:
+            syscall_i_test();
+        break;
 
     }
 }
diff --git a/test/syscall_args/shared.h b/test/syscall_args/shared.h
index 758fc2c..07fb572 100644
--- a/test/syscall_args/shared.h
+++ b/test/syscall_args/shared.h
@@ -13,4 +13,5 @@
 #define SYSCALL_F SYSCALL_BASE+6
 #define SYSCALL_G SYSCALL_BASE+7
 #define SYSCALL_H SYSCALL_BASE+8
+#define SYSCALL_I SYSCALL_BASE+9
 
diff --git a/test/syscall_args/test/tests.c b/test/syscall_args/test/tests.c
index bcfddda..6c915f5 100644
--- a/test/syscall_args/test/tests.c
+++ b/test/syscall_args/test/tests.c
@@ -169,3 +169,24 @@ void test_syscall_args_buf_pass(void) {
     }
 }
 
+void test_syscall_args_string_never_terminates(void) {
+    // run the vm
+    uvm32_run(&vmst, &evt, 1000);
+    // check for picktest syscall
+    TEST_ASSERT_EQUAL(evt.typ, UVM32_EVT_SYSCALL);
+    TEST_ASSERT_EQUAL(evt.data.syscall.code, SYSCALL_PICKTEST);
+    uvm32_arg_setval(&vmst, &evt, RET, SYSCALL_I);
+
+    uvm32_run(&vmst, &evt, 1000);
+    TEST_ASSERT_EQUAL(evt.typ, UVM32_EVT_SYSCALL);
+    TEST_ASSERT_EQUAL(evt.data.syscall.code, SYSCALL_I);
+    // To ensure c string read goes off end looking for termination...
+    memset(vmst._memory, 0xFF, UVM32_MEMORY_SIZE);
+    TEST_ASSERT_EQUAL(0, strlen(uvm32_arg_getcstr(&vmst, &evt, ARG0)));
+
+    // check for error state
+    uvm32_run(&vmst, &evt, 100);
+    TEST_ASSERT_EQUAL(evt.typ, UVM32_EVT_ERR);
+    TEST_ASSERT_EQUAL(evt.data.err.errcode, UVM32_ERR_MEM_RD);
+}
+